nRF5 action!


  • Hero Member

    So all I need now is a way for the PPI to compare the RSSI measurement it obtained above with a threshold benchmark to decide whether or not to wake the MCU, which can take it from there. From that point onward, the regular ESB code could be used. 🙂


  • Hero Member

    Nordic could have taken this a lot farther if they had included some comparison tasks, so that the PPI could make decisions about what to do next. However, I don't see that there are any that can be used for comparing an RSSI measurement against a benchmark. Too bad. 😞



  • Great that it works.

    But I'm not so convinced about the usefulness of this method, anyways.
    I know that a lot of receivers use simple RSSI measurement to implement a low power listening mode, but when you are in a noisy environment, the system will wake up quite often, draining the battery fast. And unless you live in a very remote area, 2.4 GHz IS a noisy environment.


  • Hero Member

    @Uhrheber said in nRF5 Bluetooth action!:

    Great that it works.

    But I'm not so convinced about the usefulness of this method, anyways.
    I know that a lot of receivers use simple RSSI measurement to implement a low power listening mode, but when you are in a noisy environment, the system will wake up quite often, draining the battery fast. And unless you live in a very remote area, 2.4 GHz IS a noisy environment.

    And your better alternative is....?


  • Hardware Contributor

    @NeverDie said in nRF5 Bluetooth action!:

    From the view count, it does seem that people are reading this thread, even if not many are posting.

    I'm following your work with interest of course 😉 On my side i'm pretty busy on other stuff (rpi and my HA) so i'm missing time for try..I'll be back soon on this!

    @NeverDie said in nRF5 Bluetooth action!:

    t what to do next. However, I don't see

    I thought too, about implementing this kind of listenmode for rfm69 in my HA. What i don't like so much, is I think i would need a dedicated node for the scheduling and it complicates a bit thing. I'm not fond of using gw resources for the wakeup broadcast.
    I think, maybe I'm wrong, that, ideally, the best would be "time slots" so everything would be in sync, no flooding broadcast, lost msg, collisions etc.. but that implies some work regarding the lib, and some hw issues (with simple 8bits without precise rtc).

    Keep the good work!



  • @NeverDie None, unfortunately. The manufacturer would have to take care of that, by implementing a low power mode in the receiver (maybe with reduced sensitivity), and an additional low power wakeup pattern detector.
    There are transceiver that can do that, but the nRF52 can't.

    Some of the simple 433MHz OOK receivers have a low current consumption, but they're pretty insensitive, high bandwidth and low speed, so of not much use except switching some battery powered lamp, or such.

    Some time ago I searched for a transceiver with low current receive mode, to use it in a battery powered node, that could be woken up by rf, but found nothing.
    All of the standard data transceivers are pretty power hungry.





  • @Toyman Indeed:

    Nonetheless, larger AA or AAA type
    batteries are still required to reliably achieve operation times
    of a year or longer with high advertising rates.

    As I thought.
    And for more advanced modulations, like LoRa, the power consumption is even higher.


  • Hero Member

    @Uhrheber said in nRF5 Bluetooth action!:

    Some time ago I searched for a transceiver with low current receive mode, to use it in a battery powered node, that could be woken up by rf, but found nothing.

    TI and Silicon Labs have both had chips with "wake on radio". e.g. http://www.ti.com/lit/an/swra126b/swra126b.pdf

    The Rx current consumption of the nRF52832 seems pretty good, especially with DCDC regulator enabled. Seems to me that the RSSI detection implemented in PPI is a big improvement, even in noisy environments for the following reasons: the RSSI measurement takes only 0.25us, according to the DS. That's very little overhead. If the Radio gets switched on due to a false positive on the RSSI, well, it would have had to be switched on anyway even without the RSSI. I don't see the downside to this. The more noisy the environment, the less effective the technique is, but I don't see that you'd ever really be worse off for using it.


  • Hero Member

    @d00616
    If I'm using

    sleep(1000000000);
    

    to sleep the CPU while keeping the PPI active, is there a way for the PPI to subsequently wake the CPU so that the CPU can resume where it left off? I'm not seeing any TASKS which look suitable for doing that. Or do I need an altogether different configuration for sleeping the CPU?

    Back on August 5, @RMTUCKER had suggested using:

    sleep(digitalPinToInterrupt(10), FALLING,0);
    

    If I were to go that route, I could probably have the PPI toggle PIN 10 to do a wake-up, but I found that, for whatever reason, that method of sleeping had a much higher current draw.

    [Edit: scratch that. I just tried "sleep(digitalPinToInterrupt(10), FALLING,0);", and it appears to turn-off PPI. Oddly enough, it appears to leave the RTC running, which is actually just fine by me. However, I need the PPI running too. ]



  • @Uhrheber not really. If you read carefully, they claim almost 1year battery life with 1hz (once per sec) advertising.
    Typical MYS node sends data once per minute? So, actually, 2-3 years are easily achievable.


  • Hero Member

    It turns out the cost in current consumption of waking the MCU merely to check the RSSISAMPLE result is relatively high:
    0_1505404541889_NewFile6.jpg

    The first hump is the current drawn by the PPI and RSSI sample. The second hump is the current drawn by MCU.

    Measurement Scale: 1mv=1ma.

    Anyhow, the RSSISAMPLE measurement, as reported by the MCU, is abnormally high. It may be that I need to put the radio into RX state, instead of just RXIDLE, before taking the RSSI measurement.


  • Hero Member

    This post is deleted!

  • Hero Member

    @d00616

    Are there special reserved names to always use for the IRQ handlers? e.g. RADIO_IRQHandler(void), and so on?


  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:

    to sleep the CPU while keeping the PPI active, is there a way for the PPI to subsequently wake the CPU so that the CPU can resume where it left off? I'm not seeing any TASKS which look suitable for doing that. Or do I need an altogether different configuration for sleeping the CPU?

    The PPI cannot wake up the CPU. You can try to trigger events to a timer which resumes the CPU.

    @NeverDie said in nRF5 Bluetooth action!:

    Are there special reserved names to always use for the IRQ handlers? e.g. GPIOTE_IRQHandler(void), and so on?

    The names are defined there:

    https://github.com/sandeepmistry/arduino-nRF5/blob/dc53980c8bac27898fca90d8ecb268e11111edc1/cores/nRF5/SDK/components/device/nrf52.h#L65


  • Hero Member

    @d00616 said in nRF5 Bluetooth action!:

    Yes. In a sketch, you have to put the interrupt routine into one line. You can define the interrupt only once. If you want to use the radio ISR, you can't enable the radio in MySensors.

    Does the current development software support the use of at most one ISR in total at any one time?


  • Hero Member

    @d00616

    I changed your example to use sleep(...) instead of delay(...) in the main loop, but what then becomes obvious is that the interrupts don't wake up the MCU. Well, in a sense they do, because the ISR is executed, but the MCU doesn't remain awake like it would on an Arduino. So, how does one escape the sleep mode after it has begun without waiting for it to simply time out?

    // This code is public domain
    
    #include <nrf.h>
    #include <MySensors.h>
    
    //#define RTC NRF_RTC0
    //#define RTC_IRQ RTC0_IRQn
    
    int interrupt = 0;
    
    void setup() {
      // put your setup code here, to run once:
      Serial.begin(250000);
      Serial.println("Start");
    
      // Configure RTC
      NRF_RTC0->TASKS_STOP = 1;
      NRF_RTC0->PRESCALER = 31; //1024Hz frequency
      NRF_RTC0->CC[0] = NRF_RTC0->COUNTER + (3 * 1024);
      NRF_RTC0->EVTENSET = RTC_EVTENSET_COMPARE0_Msk;
      NRF_RTC0->INTENSET = RTC_INTENSET_COMPARE0_Msk;
      NRF_RTC0->TASKS_START = 1;
      NRF_RTC0->EVENTS_COMPARE[0] = 0;
    
      // Enable interrupt
      NVIC_SetPriority(RTC0_IRQn, 15);
      NVIC_ClearPendingIRQ(RTC0_IRQn);
      NVIC_EnableIRQ(RTC0_IRQn);
      Serial.println();
      Serial.println();
      Serial.println("Starting...");
    }
    
    void loop() {
      Serial.print(millis());
      Serial.print(" ");
      Serial.print(NRF_RTC0->COUNTER);
      Serial.print(" ");
      Serial.println(interrupt);
      sleep(10000);
    }
    
    /**
     * Reset events and read back on nRF52
     * http://infocenter.nordicsemi.com/pdf/nRF52_Series_Migration_v1.0.pdf
     */
    #if __CORTEX_M == 0x04
    #define NRF5_RESET_EVENT(event)                                                 \
            event = 0;                                                                   \
            (void)event
    #else
    #define NRF5_RESET_EVENT(event) event = 0
    #endif
    
    // This must be in one line
    extern "C" { void RTC0_IRQHandler(void) { NRF5_RESET_EVENT(NRF_RTC0->EVENTS_COMPARE[0]); interrupt++; NRF_RTC0->TASKS_CLEAR = 1; }}
    

    I guess maybe the answer is to clear the SLEEPONEXIT bit in the System Control Register (SCR) before exiting the ISR? The SCR is described on page 4-19 of: http://infocenter.arm.com/help/topic/com.arm.doc.dui0553a/DUI0553A_cortex_m4_dgug.pdf
    At the moment, though, I'm not even sure how to access that register, as so far I've only seen the API for the nRF52832 generally, not the code interface for the ARM Cortex M4 per se that's inside it.



  • @NeverDie
    I am a little lost with this,I am using sleep and wake from ext int on the nrf51 and it has been working every second for the last 2 weeks.
    What kind of int are you trying to implement?


  • Hero Member

    @rmtucker said in nRF5 Bluetooth action!:

    @NeverDie
    I am a little lost with this,I am using sleep and wake from ext int on the nrf51 and it has been working every second for the last 2 weeks.
    What kind of int are you trying to implement?

    This is for the case where the PPI is doing things (like, for example, getting the radio to periodically listen for incoming packets) all while the CPU is sleeping. If, for instance, a packet is received in that mode, the CPU needs to be awoken to process it.

    So, this is different than the easier case (which I already have working) of sleeping the CPU, then it wakes up every, say, 100ms, and then the CPU controls the radio to listen for packets and then takes action if one is received. Instead, this is a case where the PPI is controlling the radio while the CPU sleeps.

    The PPI has a lot of power saving potential, so we're figuring out how best to exploit that potential.

    Also, the more general topic of how to use interrupts and ISR's on the nRF52832 (such as how many different ones can be active at once, as supported by the current development code) needs to be addressed, independent of the regular sleep(..) function.



  • This post is deleted!

  • Hero Member

    @rmtucker said in nRF5 Bluetooth action!:

    @NeverDie
    All we need right now is a controller that covers the majority of home use.
    Tried domoticz for 2 years and it covers energy use and cost really well but then is limited to saving data every 5mins and no mixed/multisensor graphs to any extent so useless for my current needs.
    Tried myHouse for 6 months and it,s graphing was great but the display of binary sensors were not in real time and it does not do energy use at all.
    I can not find a controller that seems to cover average needs for automation/energy/and realtime feedback.
    I know it's a little off topic but it is a big problem when you can build the range of mysensors using the nrf5 but then not be able to get the feedback and energy/cost stuff on the screen.
    Maybe i am just disgruntled that the controllers do not seem to keep up with the electronics very well.

    Yes, agreed, but please let's not go into that here, because it would seriously throw us off topic. You might try: https://forum.mysensors.org/topic/7178/are-folks-here-happy-with-domoticz/63 which has some useful suggestions, especially regarding Node Red and MQTT.



  • @NeverDie
    Sorry mate i have deleted it i am just a little miffed with the controller searching😠


  • Hero Member

    @NeverDie said in nRF5 Bluetooth action!:

    At the moment, though, I'm not even sure how to access that register, as so far I've only seen the API for the nRF52832 generally, not the code interface for the ARM Cortex M4 per se that's inside it.

    OK, the file core_cm4.h is where the structure that contains the SCR is defined:

    typedef struct
    {
      __IM  uint32_t CPUID;                  /*!< Offset: 0x000 (R/ )  CPUID Base Register */
      __IOM uint32_t ICSR;                   /*!< Offset: 0x004 (R/W)  Interrupt Control and State Register */
      __IOM uint32_t VTOR;                   /*!< Offset: 0x008 (R/W)  Vector Table Offset Register */
      __IOM uint32_t AIRCR;                  /*!< Offset: 0x00C (R/W)  Application Interrupt and Reset Control Register */
      __IOM uint32_t SCR;                    /*!< Offset: 0x010 (R/W)  System Control Register */
      __IOM uint32_t CCR;                    /*!< Offset: 0x014 (R/W)  Configuration Control Register */
      __IOM uint8_t  SHP[12U];               /*!< Offset: 0x018 (R/W)  System Handlers Priority Registers (4-7, 8-11, 12-15) */
      __IOM uint32_t SHCSR;                  /*!< Offset: 0x024 (R/W)  System Handler Control and State Register */
      __IOM uint32_t CFSR;                   /*!< Offset: 0x028 (R/W)  Configurable Fault Status Register */
      __IOM uint32_t HFSR;                   /*!< Offset: 0x02C (R/W)  HardFault Status Register */
      __IOM uint32_t DFSR;                   /*!< Offset: 0x030 (R/W)  Debug Fault Status Register */
      __IOM uint32_t MMFAR;                  /*!< Offset: 0x034 (R/W)  MemManage Fault Address Register */
      __IOM uint32_t BFAR;                   /*!< Offset: 0x038 (R/W)  BusFault Address Register */
      __IOM uint32_t AFSR;                   /*!< Offset: 0x03C (R/W)  Auxiliary Fault Status Register */
      __IM  uint32_t PFR[2U];                /*!< Offset: 0x040 (R/ )  Processor Feature Register */
      __IM  uint32_t DFR;                    /*!< Offset: 0x048 (R/ )  Debug Feature Register */
      __IM  uint32_t ADR;                    /*!< Offset: 0x04C (R/ )  Auxiliary Feature Register */
      __IM  uint32_t MMFR[4U];               /*!< Offset: 0x050 (R/ )  Memory Model Feature Register */
      __IM  uint32_t ISAR[5U];               /*!< Offset: 0x060 (R/ )  Instruction Set Attributes Register */
            uint32_t RESERVED0[5U];
      __IOM uint32_t CPACR;                  /*!< Offset: 0x088 (R/W)  Coprocessor Access Control Register */
    } SCB_Type;
    

    Unfortunately, I just checked its status, and it's already cleared. So, something else is causing the MCU to go back to sleep at the end of the ISR.

    The problem is that an ISR needs to be as short as possible. If something more elaborate needs to happen as a result of an interrupt, whether it be printing a bunch of debug information or something else, it should happen outside the ISR. Right now I don't see how to do that, because the MCU always immediately goes back to sleep after the ISR finishes. I suppose it must be something inside the sleep(..) routine that causes this?


  • Hero Member

    I suspect it may be the while statement in this part of the library code that's doing it:

    
    int8_t hwSleep(unsigned long ms)
    {
    	hwSleepPrepare(ms);
    	while (nrf5_rtc_event_triggered == false) {
    		hwSleep();
    	}
    	hwSleepEnd(ms);
    	return MY_WAKE_UP_BY_TIMER;
    }
    

  • Hero Member

    Yup, that was it. I excised the while-loop and re-wrote it as a differently named function, which I now call instead of sleep(..):

    int8_t myHwSleep(unsigned long ms)
    {
      hwSleepPrepare(ms);
      //while (nrf5_rtc_event_triggered == false) {
        hwSleep();
      //}
      hwSleepEnd(ms);
      return MY_WAKE_UP_BY_TIMER;
    }
    

    and it now works "correctly"--well, at least what I want it to do. 🙂 I'll flag it for @d00616, who may have good reasons for keeping it as-is.



  • @NeverDie said in nRF5 Bluetooth action!:

    From the view count, it does seem that people are reading this thread, even if not many are posting.

    I follow your journey with great interest, one day Ill find the time to do something with it 🙂



  • Just wondering if ota updates are possible with the nrf5 because it does not have the usual memory constraints?


  • Hero Member

    Epilog: It turns out that the reason I was getting erroneous readings of RSSISAMPLE by the CPU is that the radio must be turned-on when that register is being read. I had hoped it was being stored somewhere else in memory, but it's not. So, probably the best that can be done from an energy standpoint is to have the PPI pipeline the waking of the radio and the CPU from sleep, such that neither is waiting for the other to wake up in order to get work done. Ideally, the moment the RSSI measurement is taken by the PPI, the CPU would have just then fully woken up and be able to evaluate RSSISAMPLE, while the radio is still turned on.

    A different approach would be to have the PPI cyclically wake the radio into Rx mode for a period of time and then shut it down. If it received a packet, it would trigger a wake-up on the CPU. This is more or less how the RFM69's "listen mode" works. I may give this a try also so as to measure whether total current consumed is greater or less than the current consumed by the revised RSSI approach (above). I think it might. Although the radio has to remain on longer than it would if it were doing purely an RSSI measurement, it has the advantage that the CPU can remain asleep until an actual packet is received. Given that the radio spends a lot of time just ramping up after being disabled, I'm guessing the incremental Rx time needed for packet detection won't seem so much in comparison. The hard part to this approach will be timing just how long the Radio is in RX mode. Although there are technically three RTC instantiations that can be used, they all share the same prescaler.

    So, in order to create a short delay timer, I set one GPIO pin high, which charges a second GPIO pin through a very small capacitor and diode in parallel. Then, when the first GPIO pin goes low, the voltage on the second GPIO pin decays. By setting a PPI event on the second pin to trigger from a Hi2Lo transition, I'm able to create an analog delay, which varies in duration depending on the value of the capacitor. Presently, using a 2.2nF capacitor creates about a 2ms delay between the first pin going LOW and the second pin detecting a Hi2Lo event. It is that event which could be used to trigger turning off the radio after it has listened for packets, whereas it is the first pin going LOW that would have triggered turning on the radio and putting it into RX mode. This is all controlled by the PPI, so no energy needs to be used by the CPU. 🙂

    If anyone can think of a better or more of a digital way to create a predictable time delay, please do post. However, I'm using this method for now just for proof of concept purposes.


  • Hero Member

    Here's a scope capture of it:
    0_1505580444088_NewFile7.jpg

    The yellow line shows the rapid charging and then subsequent decay of voltage on the second pin. The blip on the blue line shows that after slightly more than 2ms, the Hi2Lo event was triggered, because the voltage on the second pin had dropped enough for the Hi2Lo transition to occur. As you can see, it happens at around 1v. I was able to capture it on the scope because I used that event to very briefly set a third pin (the one whose voltage is being tracked by the blue line) HIGH.

    Again, all of this is being managed by the PPI while the CPU is asleep. 🙂


  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:
    If your goal is to minimize the RX-on time, then you can trigger the RX start and stop by a timer for your minimal window where the frame must be start. Then use the bitcounter top stop the timer in case a packet is received. A shortcut to the end is disabling the RX mode. You can wakeup the CPU with the END event.

    P.S.: you can reduce the RX/TX time by enabling fast ramp up in MODECNF0 if you haven't to care about nRF51 compatibility.


  • Hero Member

    @d00616 said in nRF5 Bluetooth action!:

    @NeverDie said in nRF5 Bluetooth action!:
    If your goal is to minimize the RX-on time, then you can trigger the RX start and stop by a timer for your minimal window where the frame must be start. Then use the bitcounter top stop the timer in case a packet is received. A shortcut to the end is disabling the RX mode. You can wakeup the CPU with the END event.

    P.S.: you can reduce the RX/TX time by enabling fast ramp up in MODECNF0 if you haven't to care about nRF51 compatibility.

    Thanks! It finally dawned on me that having the PPI use the RTC's CC registers would be a far better way to schedule turning on and off the radio's RX than using the stopgap analog delay that I had devised (above). Your interrupt handler example helped me see what had been staring me in the face the entire time, but without my recognizing it as the answer to the problem. Funny how that can sometimes happen, where the whole gestalt can just suddenly change. So, thanks again for sharing your example code. This will be a much less awkward solution! 🙂


  • Hero Member

    Where exactly do I look to find all the pin mappings that are assumed for the "Generic nRF52" board? For example, what are the pin numbers that are assumed for RXI, TXO, MISO, MOSI, etc.?



  • @NeverDie
    /variants/Generic/variant.h i think


  • Hero Member

    I just now posted a source code example and hardware demo for my recently completed breakout board which uses "MyNRF52Board nRF52832" board as the reference when compiling within the Arduino IDE:
    https://www.openhardware.io/view/471#tabs-source

    I think from this point forward I'm going to use "MyNRF52Board nRF52832" for any custom boards I develop. Thanks to @d00616, it is a very convenient framework for organizing and enabling the preferred pin mappings. 🙂



  • @NeverDie That is a meandered Inverted F Antenna (IFA). It will give you better performance then a standard meandering antenna and a much smaller size then a standard 1/4wave trace antenna. Not as easy to tune however. You can read about the one that TI designed for their 2.4Ghz dongle. http://www.ti.com/lit/an/swra117d/swra117d.pdf
    Of course this is not Device dependent as you need to feed it with a 50 ohm feed point. A Pi network before between the Chip's ANT output and the Antenna is desired from a tuning standpoint.

    Note that on the nRF52 designs, the two components (Cap and Inductor) connected to the ANT pin are used for harmonic filtering AND impedance matching and has nothing to do with the antenna tuning other to present a 50ohm feed point.


  • Hero Member

    @Jokgi said in nRF5 Bluetooth action!:

    @NeverDie That is a meandered Inverted F Antenna (IFA). It will give you better performance then a standard meandering antenna and a much smaller size then a standard 1/4wave trace antenna. Not as easy to tune however. You can read about the one that TI designed for their 2.4Ghz dongle. http://www.ti.com/lit/an/swra117d/swra117d.pdf
    Of course this is not Device dependent as you need to feed it with a 50 ohm feed point. A Pi network before between the Chip's ANT output and the Antenna is desired from a tuning standpoint.

    Note that on the nRF52 designs, the two components (Cap and Inductor) connected to the ANT pin are used for harmonic filtering AND impedance matching and has nothing to do with the antenna tuning other to present a 50ohm feed point.

    It looks the same as the antenna on the Ebyte E73-2G4M04S nRF52832 module. Is there any difference? i.e. are you just supplying background information, or are you making a suggestion for improvement?



  • @NeverDie nRFgo Studio uses the Segger J-link firmware. When using the Softdevice make sure that your application does not start below the top of the Softdevice or you will get a error on most programmers that there is something located in that protected space. If it does not see this as a protected area then you will corrupt the Softdevice.

    Most programmers only need the two SWD lines, ground and a voltage reference from your target board back to the programmer. This is to tell the programmer you have a target board connected and what voltage it is running on. Note that the nRF52-DK does NOT have voltage translators on the programming lines (P19 and P20) so you must be powering your target boards with 3vdc to 3.3vdc. (I have tested down to 2.8vdc but it is not guaranteed to work consistently.) Not sure about ST or other programmers.



  • @NeverDie someone did not read the datasheet. The harmonic filter / impedance matching network on the output of Pin 30 (ANT) is connected incorrectly. There needs to be abolded text Cap from ANT out to Pin 31 ONLY. (Not connected to any other ground pour as it seems they did here. Seems to be a few "extra components between there and the Antenna matching network too.

    From the nRF52832 datasheet.
    bolded text53.8 PCB layout example
    The PCB layout shown below is a reference layout for the QFN package with internal LDO setup.
    Important: Pay attention to how the capacitor C3 is grounded. It is not directly connected to the
    ground plane, but grounded via VSS pin 31. This is done to create additional filtering of harmonic
    components.[link text](link url)



  • @NeverDie Pretty much a reference only. In a previous post you inquired about the grounding on the meandering antenna. I posted the TI application note as a frame of reference only. However if you do create your own module you should be aware that the two matching components coming off the ANT pin are NOT antenna matching components but are three for output impedance matching and also acts as a low pass filter. Pi network is still required for tuning of the antenna. (may not use all three components after tuning)


  • Hero Member

    @Jokgi said in nRF5 Bluetooth action!:

    you must be powering your target boards with 3vdc to 3.3vdc. (I have tested down to 2.8vdc but it is not guaranteed to work consistently.) Not sure about ST or other programmers.

    Thanks for reminding me of this. It turns out to be true for the J-Link programmers which are for sale on Aliexpress.com as well.



  • @NeverDie I am not sure about all the boards for sell on that site. but I would have to say that any J-link programmer that is packaged as such for $12-$40 dollars is probably counterfeit. Updating these items with newer J-link firmware would more then likely disable them. (On purpose) You may wish to contact Segger in Boston prior to spending money on these potential clones. I would be interested to hear what experiences other people have had with the products from that site.

    The genuine J-link and j-link plus programmers are over $400.00 as you can see on the Digi-Key website. Per the Segger license agreements, the only J-link 0B devices that are able to be sold are to be bundled with a Evaluation / Development kit such as the nRF52-DK, ST, Rigato, and other semiconductor / module manufacture's dev kits.


  • Hero Member

    @Jokgi said in nRF5 Bluetooth action!:

    @NeverDie I am not sure about all the boards for sell on that site. but I would have to say that any J-link programmer that is packaged as such for $12-$40 dollars is probably counterfeit. Updating these items with newer J-link firmware would more then likely disable them. (On purpose) You may wish to contact Segger in Boston prior to spending money on these potential clones. I would be interested to hear what experiences other people have had with the products from that site.

    The genuine J-link and j-link plus programmers are over $400.00 as you can see on the Digi-Key website. Per the Segger license agreements, the only J-link 0B devices that are able to be sold are to be bundled with a Evaluation / Development kit such as the nRF52-DK, ST, Rigato, and other semiconductor / module manufacture's dev kits.

    When would I need to upgrade the firmware? At least for now it seems to work just fine.


  • Hardware Contributor

    @Jokgi said in nRF5 Bluetooth action!:

    @NeverDie I am not sure about all the boards for sell on that site. but I would have to say that any J-link programmer that is packaged as such for $12-$40 dollars is probably counterfeit. Updating these items with newer J-link firmware would more then likely disable them. (On purpose)

    Yes they are of course counterfeit, and using old firmware. You have a message when you use them with Segger software asking you to upgrade to newer firmware and if you accept your programmer is disabled (web is full of solutions to reflash a firmware).
    But if you don't upgrade the firmware it works fine as a SWD programmer, at least for basic use (programming). I have not tried any debugging.



  • @Nca78 Corrrect. It seems to me that a < 50 dollar Nordic nRF52 based Dev kit (or similar) which can be updated would be much less hassle.


  • Hero Member

    Are we limited to using RTC0? I've tried switching to RTC1 and RTC2, and I get the sense there are conflicts with both of them and the MySensors code if they're used.


  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:

    Are we limited to using RTC0? I've tried switching to RTC1 and RTC2, and I get the sense there are conflicts with both of them and the MySensors code if they're used.

    RTC1 is blocked by arduino (nRF5/delay.c) and RTC0 (nRF51) and RTC2 (nRF52) is used in MySensors (hal/architecture/MyHwNRF5.cpp)


  • Hero Member

    Success. I now have a "listen mode" for the nRF52832 radio that's completely controlled by the PPI while the MCU sleeps. Presently, it wakes up the radio every 100ms and listens for 1ms. This means no wasted power from oversight by the MCU. Using just the PPI, I can control to within about 30us over how long to make the cycle period and/or the listening duration.
    0_1505768284420_NewFile2.jpg
    0_1505768305717_NewFile1.jpg

    The scope shots show the current drawn. Scale: 1mv=1ma. As you can see, the DCDC regulator is engaged.

    Next step will be to have packet receipt wake up the MCU via an ISR, so that the packet can be processed. After that, I'll see how narrow I can make the receive window and still receive packets reliably. I think under 100us will be possible. Maybe even less than 60us if the bitrate is 2mbps. 🙂



  • @NeverDie Great Job!!!! Suggestion... If you are going to use the BTLE Softdevice you will have a smaller receive window if you use the external 32khz crystal option rather then the internal 32khz RC one. (+/- 20ppm with the crystal vs +/- 250 or 500ppm with the RC.


  • Hero Member

    At the extreme, one of the questions that will need answering is: what's the minimum number of bytes in a transmitted frame that you really do need before the receiver starts receiving garbage packets? For instance, a 10 byte frame, which should be more than adequate, would take 40us of airtime to either transmit or receive at 2mbps bitrate. One could get to a lower number by maybe sending a null packet as a wake-up packet, in which case maybe you also don't need CRC. So, that leaves you with some preamble, a network ID, and maybe a destination ID--or about 5 bytes. So, that would be around 20us of airtime. One could shrink that further by reducing the number of network ID bytes, but too much of that and possibly one starts to receive garbage packets.

    The RFM69 doesn't try to decode packets whose RSSI is below a specific programmable threshhold. I don't believe the nRF52 radio uses RSSI as a filter in that way though. It seems that the nRF52832 radio tries to decode whatever it's receiving, regardless of the RSSI. Or, at least, that's how I remember it. Anyone else played around with it?


  • Hero Member

    @d00616

    I adapted your RTC0 code for handling IRQ's, and it looks like this:

    
      NRF_RADIO->INTENSET = B100;  //interrupt MCU if a payload is received.
      // Enable interrupt
      NVIC_SetPriority(RADIO_IRQn, 15);
      NVIC_ClearPendingIRQ(RADIO_IRQn);
      NVIC_EnableIRQ(RADIO_IRQn);
    
    #if __CORTEX_M == 0x04
    #define NRF5_RESET_EVENT(event)                                                 \
            event = 0;                                                                   \
            (void)event
    #else
    #define NRF5_RESET_EVENT(event) event = 0
    #endif
    
    
    // This must be in one line
    extern "C" { void RADIO_IRQHandler(void) {packetCounter++; NRF5_RESET_EVENT(NRF_RADIO->EVENTS_PAYLOAD); NRF_RADIO->EVENTS_PAYLOAD=0; }}
    

    Question: Is

    NRF5_RESET_EVENT(NRF_RADIO->EVENTS_PAYLOAD); 
    

    doing anything more than

    NRF_RADIO->EVENTS_PAYLOAD=0;
    

    is?


  • Hero Member

    The good news is that I can now literally "see" that the listen-mode is receiving packets, because I've programmed the PPI to toggle an LED every time a packet is received (and it only toggles the LED if and only if I know that I'm sending the node packets from a different node). The bad news is that--so far, anyway--it doesn't appear to trigger an IRQ event that wakes up the MCU and runs the ISR.


  • Mod

    @NeverDie it seems like the preamble can be configured to be either 8 or 16 bits. Not sure if that's of any use, but I've been thinking about adjusting the LoRa preamble to get better sleep times. Maybe that could be applicable for nrf as well.


  • Hero Member

    It turns out that using just the standard radiohead packet/frame structure, I'm able to 100% reliably receive a two byte string (in this case, the letter "H" followed by a zero as the termination character) using the above PPI solution with a receive window of about 200ms. That includes preamble, CRC, and a long network ID number.

    I'm pleased with that result. It's vastly better than without the PPI solution.


  • Hero Member

    OK, I'm going to start with this, which works:

    //A simplified re-mix of code mostly written by d00616
    
    #include <nrf.h>
    #include <MySensors.h>
    
    int interrupt = 0;
    uint32_t theCounter;
    
    
    int8_t myHwSleep(unsigned long ms)
    {
      hwSleepPrepare(ms);
      //while (nrf5_rtc_event_triggered == false) {
        hwSleep();
      //}
      hwSleepEnd(ms);
      return MY_WAKE_UP_BY_TIMER;
    }
    
    
    void setup() {
      // put your setup code here, to run once:
      Serial.begin(250000);
      Serial.println("Start");
    
      // Configure RTC
      NRF_RTC0->TASKS_STOP = 1;
      NRF_RTC0->PRESCALER = 32;  
      NRF_RTC0->CC[0] = NRF_RTC0->COUNTER + (655);  //comparison for when to turn off the Rx.
      NRF_RTC0->EVTENSET = RTC_EVTENSET_COMPARE0_Msk;
      NRF_RTC0->INTENSET = RTC_INTENSET_COMPARE0_Msk;
      NRF_RTC0->TASKS_START = 1;
      NRF_RTC0->EVENTS_COMPARE[0] = 0;
    
      // Enable interrupt
      NVIC_SetPriority(RTC0_IRQn, 15);
      NVIC_ClearPendingIRQ(RTC0_IRQn);
      NVIC_EnableIRQ(RTC0_IRQn);
      Serial.println();
      Serial.println();
      Serial.println("Starting...");
    }
    
    
    void loop() {
    
      Serial.print(millis());
      Serial.print(" ");
      Serial.print(theCounter);
      Serial.print(" ");
      Serial.println(interrupt);
      myHwSleep(5000000);
    }
    
    /**
     * Reset events and read back on nRF52
     * http://infocenter.nordicsemi.com/pdf/nRF52_Series_Migration_v1.0.pdf
     */
    #if __CORTEX_M == 0x04
    #define NRF5_RESET_EVENT(event)                                                 \
            event = 0;                                                                   \
            (void)event
    #else
    #define NRF5_RESET_EVENT(event) event = 0
    #endif
    
    // This must be in one line
    extern "C" { void RTC0_IRQHandler(void) {   theCounter=NRF_RTC0->COUNTER; NRF5_RESET_EVENT(NRF_RTC0->EVENTS_COMPARE[0]); interrupt++; NRF_RTC0->TASKS_CLEAR = 1; }}
    

    and see if I can generate equivalent code which triggers on a pin change instead of an RTC event. If I can get that to work, then I'll take another stab at getting it to work based on the radio receiving a packet.


  • Hero Member

    I was only partially done with the code, but I decided to run it anyway. Oddly enough, even though there is no reference to " RTC0_IRQHandler(void)" as being the event handler, it gets fired off anyway whenever I press the button (pin P0.16):

    
    #include <nrf.h>
    #include <MySensors.h>
    
    int interrupt = 0;
    uint32_t theCounter;
    
    
    int8_t myHwSleep(unsigned long ms)
    {
      hwSleepPrepare(ms);
       hwSleep();
      hwSleepEnd(ms);
      return MY_WAKE_UP_BY_TIMER;
    }
    
    
    void setup() {
      // put your setup code here, to run once:
      Serial.begin(250000);
      Serial.println("Start");
    
      //Configure GPIOTE 
      NRF_GPIOTE->CONFIG[0]=0x31001;  // Toggle Event; Pin P0.16; Event Mode 
                                      //So, any pin change on P0.16 will trigger an event.
                                       //On the Nordic nRF52 DK, Pin 0.16 is a button.
                                       
      NRF_GPIOTE->CONFIG[1]=0x131203;  //Initial setting: HIGH; Toggle Task; Pin P0.18; Task Mode
                                       //On the Nordic nRF52 DK, Pin 0.18 is an LED.
                                       //Note: initial setting of HIGH means that the LED will be initially OFF.
    
      NRF_GPIOTE->INTENSET=1;  //Enable an event on Pin P0.16 to trigger an interrupt.
                                       
      NRF_PPI->CH[0].EEP = (uint32_t)&NRF_GPIOTE->EVENTS_IN[0];  //P0.16 pin change occured.
      NRF_PPI->CH[0].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[1]; //Toggle LED on pin P0.18.
      
      NRF_PPI->CHENSET=B1; //enable Channel 0.
    
      // Enable interrupt
      NVIC_SetPriority(GPIOTE_IRQn, 15);
      NVIC_ClearPendingIRQ(GPIOTE_IRQn);
      NVIC_EnableIRQ(GPIOTE_IRQn);
      Serial.println();
      Serial.println();
      Serial.println("Starting...");
    }
    
    
    void loop() {
    
      Serial.print(millis());
      Serial.print(" ");
      Serial.print(theCounter);
      Serial.print(" ");
      Serial.println(interrupt);
      myHwSleep(5000000);
    }
    
    /**
     * Reset events and read back on nRF52
     * http://infocenter.nordicsemi.com/pdf/nRF52_Series_Migration_v1.0.pdf
     */
    #if __CORTEX_M == 0x04
    #define NRF5_RESET_EVENT(event)                                                 \
            event = 0;                                                                   \
            (void)event
    #else
    #define NRF5_RESET_EVENT(event) event = 0
    #endif
    
    // This must be in one line
    extern "C" { void RTC0_IRQHandler(void) {   theCounter=NRF_RTC0->COUNTER; NRF5_RESET_EVENT(NRF_RTC0->EVENTS_COMPARE[0]); interrupt++; NRF_RTC0->TASKS_CLEAR = 1; }}
    

    So, it looks as though, at present, there can be only a single ISR for an entire sketch?


  • Hero Member

    Interesting result. I eliminated most of the sample code, and it actually manages to work even without an ISR! Instead of running an ISR, it appears to simply wake up from exactly where it last fell asleep. Then it continues running until it's put to sleep again:

    #include <nrf.h>
    #include <MySensors.h>
    
    uint32_t buttonPressCounter=0;
    
    
    int8_t myHwSleep(unsigned long ms)
    {
      hwSleepPrepare(ms);
      hwSleep();
      hwSleepEnd(ms);
      return MY_WAKE_UP_BY_TIMER;
    }
    
    
    void setup() {
      // put your setup code here, to run once:
      Serial.begin(250000);
      Serial.println("Start");
    
      //Configure GPIOTE 
      NRF_GPIOTE->CONFIG[0]=0x31001;  // Toggle Event; Pin P0.16; Event Mode 
                                      //So, any pin change on P0.16 will trigger an event.
                                       //On the Nordic nRF52 DK, Pin 0.16 is a button.
                                       
      NRF_GPIOTE->CONFIG[1]=0x131203;  //Initial setting: HIGH; Toggle Task; Pin P0.18; Task Mode
                                       //On the Nordic nRF52 DK, Pin 0.18 is an LED.
                                       //Note: initial setting of HIGH means that the LED will be initially OFF.
    
      NRF_GPIOTE->INTENSET=1;  //Enable an event on Pin P0.16 to trigger an interrupt.
                                       
      NRF_PPI->CH[0].EEP = (uint32_t)&NRF_GPIOTE->EVENTS_IN[0];  //P0.16 pin change occured.
      NRF_PPI->CH[0].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[1]; //Toggle LED on pin P0.18.
      
      NRF_PPI->CHENSET=B1; //enable Channel 0.
    
      // Enable interrupt
      NVIC_SetPriority(GPIOTE_IRQn, 15);
      NVIC_ClearPendingIRQ(GPIOTE_IRQn);
      NVIC_EnableIRQ(GPIOTE_IRQn);
      Serial.println();
      Serial.println();
      Serial.println("Starting...");
    }
    
    
    void loop() {
      Serial.print("time=");
      Serial.print(millis());
      Serial.print(", buttonPressCounter=");
      Serial.println(buttonPressCounter++);
      myHwSleep(5000000);
    }
    

  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:

    Question: Is
    NRF5_RESET_EVENT(NRF_RADIO->EVENTS_PAYLOAD);

    doing anything more than
    NRF_RADIO->EVENTS_PAYLOAD=0;

    is?

    Yes. It reads back the register. http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52/dita/nrf52/migration/functional.html?cp=2_4_0


  • Hero Member

    Whenever I use:

    #include <MySensors.h>
    

    on the nRF52832, there is around a 10 second delay between the end of "void startup()" and the beginning of "loop()". Why is that, and what is the MySensors library doing during that interval?


  • Mod

    @NeverDie it depends on the value of MY_TRANSPORT_WAIT_READY_MS
    See https://github.com/mysensors/MySensors/issues/927 for a discussion on what happens when - we're trying to clarify the documentation.


  • Hero Member

    @d00616 said in nRF5 Bluetooth action!:

    P.S.: you can reduce the RX/TX time by enabling fast ramp up in MODECNF0 if you haven't to care about nRF51 compatibility.

    Thanks for the tip. I tried it both ways. The first scope capture below is taken without MODECNF0 enabled on bit 0, and the second is with it enabled on bit 0.
    0_1505865330798_NewFile5.png
    0_1505865340675_NewFile6.png

    I don't really see any difference. Do you?
    Scale: 1mv=1ma. Scope captures of current drawn.

    Maybe @jokgi can comment? His bio says he's a Senior Field Application Engineer at Nordic Semiconductor.
    Maybe he sees (or knows) something that's not apparent about the fast ramp enable bit?


  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:

    Whenever I use:
    #include <MySensors.h>

    on the nRF52832, there is around a 10 second delay between the end of "void startup()" and the beginning of "loop()". Why is that, and what is the MySensors library doing during that interval?

    As an alternative, you can define '#define MY_CORE_ONLY' and use ' transportInit(); transportSetAddress(MY_NODE_ID);' to initialize the radio. This dosn't work at the moment with the nRF5. I'm currently looking what the reason is. All radio registers are equal when it's initialized after MySensors normal and my setup(). It's not able to send or receive packages.

    Maybe someone has an idea about the reason. Here is my code for nRF5 and other with nRF24.

    // Undefine to work in gateway mode
    #define MY_CORE_ONLY
    
    
    #define MY_NODE_ID (0)
    
    // Enable debug
    #define MY_DEBUG
    #define MY_DEBUG_VERBOSE_RF24
    #define MY_DEBUG_VERBOSE_NRF5_ESB
    
    // Enable and select radio type attached
    #ifndef ARDUINO_ARCH_NRF5
    #define MY_RADIO_NRF24
    #else
    #define MY_RADIO_NRF5_ESB
    #include <nrf.h>
    #endif
    //#define MY_RADIO_RFM69
    //#define MY_RADIO_RFM95
    
    //#define MY_OTA_LOG_SENDER_FEATURE
    //#define MY_OTA_LOG_RECEIVER_FEATURE
    
    #ifndef MY_CORE_ONLY
    #define MY_GATEWAY_SERIAL
    #endif
    #include <MySensors.h>
    
    void state() {
    #ifdef ARDUINO_ARCH_NRF5
     Serial.println("----------------------------------");
     Serial.print("NRF_RADIO->STATE  ");
     Serial.println(NRF_RADIO->STATE, HEX);
     Serial.print("NRF_RADIO->EVENTS_READY  ");
     Serial.println(NRF_RADIO->EVENTS_READY, HEX);
     Serial.print("NRF_RADIO->EVENTS_ADDRESS  ");
     Serial.println(NRF_RADIO->EVENTS_ADDRESS, HEX);
     Serial.print("NRF_RADIO->EVENTS_PAYLOAD  ");
     Serial.println(NRF_RADIO->EVENTS_PAYLOAD, HEX);
     Serial.print("NRF_RADIO->EVENTS_END  ");
     Serial.println(NRF_RADIO->EVENTS_END, HEX);
     Serial.print("NRF_RADIO->EVENTS_DISABLED  ");
     Serial.println(NRF_RADIO->EVENTS_DISABLED, HEX);
     Serial.print("NRF_RADIO->EVENTS_DEVMATCH  ");
     Serial.println(NRF_RADIO->EVENTS_DEVMATCH, HEX);
     Serial.print("NRF_RADIO->EVENTS_DEVMISS  ");
     Serial.println(NRF_RADIO->EVENTS_DEVMISS, HEX);
     Serial.print("NRF_RADIO->EVENTS_RSSIEND  ");
     Serial.println(NRF_RADIO->EVENTS_RSSIEND, HEX);
     Serial.print("NRF_RADIO->EVENTS_BCMATCH  ");
     Serial.println(NRF_RADIO->EVENTS_BCMATCH, HEX);
     Serial.print("NRF_RADIO->CRCSTATUS  ");
     Serial.println(NRF_RADIO->CRCSTATUS, HEX);
     Serial.print("NRF_RADIO->RXMATCH  ");
     Serial.println(NRF_RADIO->RXMATCH, HEX);
     Serial.print("NRF_RADIO->RXCRC  ");
     Serial.println(NRF_RADIO->RXCRC, HEX);
     Serial.print("NRF_RADIO->DAI  ");
     Serial.println(NRF_RADIO->DAI, HEX);
     Serial.print("NRF_RADIO->PACKETPTR  ");
     Serial.println(NRF_RADIO->PACKETPTR, HEX);
     Serial.print("NRF_RADIO->FREQUENCY  ");
     Serial.println(NRF_RADIO->FREQUENCY, HEX);
     Serial.print("NRF_RADIO->TXPOWER  ");
     Serial.println(NRF_RADIO->TXPOWER, HEX);
     Serial.print("NRF_RADIO->MODE  ");
     Serial.println(NRF_RADIO->MODE, HEX);
     Serial.print("NRF_RADIO->PCNF0  ");
     Serial.println(NRF_RADIO->PCNF0, HEX);
     Serial.print("NRF_RADIO->PCNF1  ");
     Serial.println(NRF_RADIO->PCNF1, HEX);
     Serial.print("NRF_RADIO->BASE0  ");
     Serial.println(NRF_RADIO->BASE0, HEX);
     Serial.print("NRF_RADIO->BASE1  ");
     Serial.println(NRF_RADIO->BASE1, HEX);
     Serial.print("NRF_RADIO->PREFIX0  ");
     Serial.println(NRF_RADIO->PREFIX0, HEX);
     Serial.print("NRF_RADIO->PREFIX1  ");
     Serial.println(NRF_RADIO->PREFIX1, HEX);
     Serial.print("NRF_RADIO->TXADDRESS  ");
     Serial.println(NRF_RADIO->TXADDRESS, HEX);
     Serial.print("NRF_RADIO->RXADDRESSES  ");
     Serial.println(NRF_RADIO->RXADDRESSES, HEX);
     Serial.print("NRF_RADIO->CRCCNF  ");
     Serial.println(NRF_RADIO->CRCCNF, HEX);
     Serial.print("NRF_RADIO->SHORTS  ");
     Serial.println(NRF_RADIO->SHORTS, HEX);
     Serial.print("NRF5_RADIO_TIMER->MODE ");
     Serial.println(NRF5_RADIO_TIMER->MODE);
     Serial.print("NRF5_RADIO_TIMER->BITMODE ");
     Serial.println(NRF5_RADIO_TIMER->BITMODE);
     Serial.print("NRF5_RADIO_TIMER->SHORTS ");
     Serial.println(NRF5_RADIO_TIMER->SHORTS);
     Serial.print("NRF5_RADIO_TIMER->PRESCALER ");
     Serial.println(NRF5_RADIO_TIMER->PRESCALER);
      // Reset compare events
    #ifdef NRF51
      for (uint8_t i=0;i<4;i++) {
    #else
      for (uint8_t i=0;i<6;i++) {
    #endif
     Serial.print("NRF5_RADIO_TIMER->EVENTS_COMPARE[");
     Serial.print(i);
     Serial.print("] ");
     Serial.println(NRF5_RADIO_TIMER->EVENTS_COMPARE[i]);
    }
    Serial.println("----------------------------------");
    #endif
    }
    
    void setup() {
      Serial.begin(115200);
      
      #ifdef MY_CORE_ONLY
      transportInit();
      delay(1000);
      transportSetAddress(MY_NODE_ID);
      #endif
    }
    
    void loop() {
      state();
    
      #ifdef MY_CORE_ONLY
      // Check for packages
      if (transportAvailable()) {
        uint8_t buffer[256];
        uint8_t num = transportReceive(&buffer);
        for (int i=0;i<num;i++) {
          if (buffer[i]<0x10) Serial.print("0");
          Serial.print(buffer[i], HEX);
          Serial.print(" ");
        }
        Serial.println();
      }
      #endif
    
      // Pause
      //sleep(1000); don't use this on SAMD. The device must be restored with reset doubleclick
      delay(1000);
      
      // Send data
      //transportSend(MY_NODE_ID, "abcd", 4, false);
    }
    

    @NeverDie said in nRF5 Bluetooth action!:

    @d00616 said in nRF5 Bluetooth action!:

    P.S.: you can reduce the RX/TX time by enabling fast ramp up in MODECNF0 if you haven't to care about nRF51 compatibility.

    Thanks for the tip. I tried it both ways. The first scope capture below is taken without MODECNF0 enabled on bit 0, and the second is with it enabled on bit 0.

    Have you checked the MODECNF0 register after ramp up? Maybe the register must be changed in a specific state?


  • Hero Member

    Not sure why, but so far I haven't been able to get the radio to generate an interrupt (after it receives a packet) that directly wakes the MCU. So, as a workaround, I'm using PPI to have the radio toggle a GPIO output pin, which is directly shorted to a GPIO input pin. Changes in that input pin are able to trigger an interrupt which wakes the MCU. So, in this circuitous way, I'm able to get the radio to wake the MCU. It works, but with a propagation delay, and obviously I shouldn't have to be doing it so indirectly.

    Has anyone else had any success yet in waking the MCU from sleep upon packet receipt by the radio?

    Which interrupt register in the MCU is the interrupt generated by the radio tied to? Perhaps it needs to be premptively cleared. I think the next step is to check whether the radio's interrupt is even being received by the MCU.


  • Contest Winner

    @d00616 said in nRF5 Bluetooth action!:

    Maybe someone has an idea about the reason. Here is my code for nRF5 and other with nRF24.

    Now, I have the NRF5_ESB working under MY_CORE_ONLY condition. The HFCLK is not initialized. I do some code changes to allow using the radio in core only mode.


  • Hero Member

    @d00616 said in nRF5 Bluetooth action!:

    @d00616 said in nRF5 Bluetooth action!:

    Maybe someone has an idea about the reason. Here is my code for nRF5 and other with nRF24.

    Now, I have the NRF5_ESB working under MY_CORE_ONLY condition. The HFCLK is not initialized. I do some code changes to allow using the radio in core only mode.

    I'm not sure what that means. Can you clarify what is working and what isn't, especially with regards to interrupts? If the code isn't yet ready, I'll just stick with the GPIO pins solution (above) and revisit this topic again at some future date when its further along.


  • Hero Member

    Actually, there's another reason for wanting to avoid using the GPIO pins to intermediate waking up the MCU: earlier measurements in this thread showed that using the GPIO's in anything other than a "disconnected" state noticeably increases the current draw while sleeping.


  • Hero Member

    @d00616 said in nRF5 Bluetooth action!:

    The HFCLK is not initialized.

    Not sure if it helps you at all, but to save extra energy I'm using the PPI to turn-on HFCLK before the Rx "listen-mode" begins, and then turn it off after the receiver is subsequently put to sleep:

      //Note: radio is assumed to be sleeping by this point, and with high frequency crystal oscillator turned off.
      NRF_PPI->CH[0].EEP = (uint32_t)&NRF_RTC0->EVENTS_OVRFLW;  //when COUNTER overflows.
      NRF_PPI->CH[0].TEP = (uint32_t)&NRF_CLOCK->TASKS_HFCLKSTART;  //turn-on the HF crystal oscillator
    
      NRF_PPI->CH[1].EEP = (uint32_t)&NRF_CLOCK->EVENTS_HFCLKSTARTED;  //After HF Clock started.
      NRF_PPI->CH[1].TEP = (uint32_t)&NRF_RADIO->TASKS_RXEN;  //turn on the radio receiver
    
      NRF_PPI->CH[2].EEP = (uint32_t)&NRF_RADIO->EVENTS_READY;  //After event READY, radio shall be in state RXIDLE.
      NRF_PPI->CH[2].TEP = (uint32_t)&NRF_RADIO->TASKS_START;  //Move from RXIDLE mode into RX mode.
    
      NRF_PPI->CH[3].EEP = (uint32_t)&NRF_RTC0->EVENTS_COMPARE[0];  // If time to turn off the radio receiver
      NRF_PPI->CH[3].TEP = (uint32_t)&NRF_RADIO->TASKS_STOP; //Move radio from RX mode back into RXIDLE mode
      
      NRF_PPI->CH[4].EEP = (uint32_t)&NRF_RTC0->EVENTS_COMPARE[1];  // If enough time has passed
      NRF_PPI->CH[4].TEP = (uint32_t)&NRF_RADIO->TASKS_DISABLE; //Sleep the radio
      NRF_PPI->FORK[4].TEP = (uint32_t)&NRF_CLOCK->TASKS_HFCLKSTOP; //Turn-off the high frequency crystal oscillator 
      
      NRF_PPI->CH[5].EEP = (uint32_t)&NRF_RTC0->EVENTS_COMPARE[2];  // If 100ms has passed
      NRF_PPI->CH[5].TEP = (uint32_t)&NRF_RTC0->TASKS_TRIGOVRFLW; //Set COUNTER so that it will overflow in 16 ticks.
    
      NRF_PPI->CH[6].EEP = (uint32_t)&NRF_RADIO->EVENTS_END;  //packet received.
      NRF_PPI->CH[6].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[1]; //Make pin P0.18. be LOW (turn on the LED).
    
      NRF_PPI->CH[7].EEP = (uint32_t)&NRF_GPIOTE->EVENTS_IN[0];  //P0.16 pin change occured.
      NRF_PPI->CH[7].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[2]; //Make pin P0.17. be LOW (turn on the LED).
      
      NRF_PPI->CHENSET=B11111111; //enable Channels 7,6,5,4,3,2,1,and 0.
    

    It works. 🙂


  • Hero Member

    @d00616

    Can you see any reason as to why the radio isn't waking the MCU after it receives a packet? Here's the entire sketch:

    #include <nrf.h>
    //#include <MySensors.h>
    #include <RH_NRF51.h>
    
    // Singleton instance of the radio driver
    RH_NRF51 nrf51;
    
    bool toggle=true;
    uint32_t packetCounter=0;
    uint8_t myBuffer[20];  //required buffer for transmitting packet
    uint8_t my_default_network_address[] = {0xE7, 0xE7, 0xE7, 0xE7, 0xE7};
    
    bool mySetNetworkAddress(uint8_t* address, uint8_t len)
    {
        if (len < 3 || len > 5)
      return false;
    
        // First byte is the prefix, remainder are base
        NRF_RADIO->PREFIX0    = ((address[0] << RADIO_PREFIX0_AP0_Pos) & RADIO_PREFIX0_AP0_Msk);
        uint32_t base;
        memcpy(&base, address+1, len-1);
        NRF_RADIO->BASE0 = base;
    
        NRF_RADIO->PCNF1 =  (
      (((sizeof(myBuffer)) << RADIO_PCNF1_MAXLEN_Pos)  & RADIO_PCNF1_MAXLEN_Msk)  // maximum length of payload
      | (((0UL)        << RADIO_PCNF1_STATLEN_Pos) & RADIO_PCNF1_STATLEN_Msk) // expand the payload with 0 bytes
      | (((len-1)      << RADIO_PCNF1_BALEN_Pos)   & RADIO_PCNF1_BALEN_Msk)); // base address length in number of bytes.
    
        return true;
    }
    
    void myHwSleepPrepare(unsigned long ms)
    {
      // Idle serial device
      NRF_UART0->TASKS_STOPRX = 1;
      NRF_UART0->TASKS_STOPTX = 1;
      NRF_UART0->TASKS_SUSPEND = 1;
    
      //NRF_CLOCK->TASKS_HFCLKSTOP = 1;
      
      // Enable low power sleep mode
      NRF_POWER->TASKS_LOWPWR = 1;
    }
    
    // Sleep in System ON mode
    inline void doTheSleep()
    {
      __WFE();
      __SEV();
      __WFE();
    }
    
    void myHwSleepEnd(unsigned long ms)
    {
      // Start HFCLK
      //if (nrf5_pwr_hfclk) {
      if (false) {
        NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;
        NRF_CLOCK->TASKS_HFCLKSTART = 1;
        while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
          ;
        // Enable low latency sleep mode
        NRF_POWER->TASKS_CONSTLAT = 1;
      }
    
       // Start serial device
    //#ifndef MY_DISABLED_SERIAL
      NRF_UART0->TASKS_STARTRX = 1;
      NRF_UART0->TASKS_STARTTX = 1;
    //#endif
    }
    
    void myHwSleep(unsigned long ms)
    {
      myHwSleepPrepare(ms);
      doTheSleep();
      //now sleeping
      myHwSleepEnd(ms);
    
    }
    
    
    
    void setup() {
      Serial.begin(250000);
      Serial.println();
      Serial.println("Starting...");
      Serial.flush();
    
      NRF_POWER->DCDCEN=1;  //enable the DCDC voltage regulator as the default.
      
      // Configure RTC
      NRF_RTC0->TASKS_STOP = 1;  //stop the RTC counter so that it can be configured without incident
    
      // Enable interrupt
      //NVIC_SetPriority(GPIOTE_IRQn, 15);
      //NVIC_ClearPendingIRQ(GPIOTE_IRQn);
      //NVIC_EnableIRQ(GPIOTE_IRQn);
      
      NVIC_SetPriority(RADIO_IRQn, 15);
      NVIC_ClearPendingIRQ(RADIO_IRQn);
      NVIC_EnableIRQ(RADIO_IRQn);
      NRF_RADIO->INTENSET = B1000;  //interrupt MCU if a packet is received.
      while (NRF_RADIO->INTENSET != B1000) {}  //wait until confirmed
          
      //NRF_GPIOTE->INTENSET = 1;  //interrupt MCU if change detected on pin P0.16.
      //while (NRF_GPIOTE->INTENSET != 1) {}  //wait until confirmed
      
      Serial.print("LFCLKSTAT=0X");
      Serial.print(NRF_CLOCK->LFCLKSTAT,HEX);
      Serial.print("=B");
      Serial.println(NRF_CLOCK->LFCLKSTAT,BIN);
      Serial.flush();
    
      NRF_RADIO->FREQUENCY=123;
      NRF_RADIO->MODE=1;  //set 2Mbps datarate.
      NRF_RADIO->MODECNF0=1;  //enable fast ramp-up of radio from DISABLED state.
    
      if (!nrf51.init())
        Serial.println("init failed");
      mySetNetworkAddress(my_default_network_address, sizeof(my_default_network_address));   
      
      if ((NRF_CLOCK->LFCLKSTAT)>>2) {//if LF clock is running
        NRF_CLOCK->TASKS_LFCLKSTOP=1;  //stop the clock
        while ((NRF_CLOCK->LFCLKSTAT)& 1)  {}  //busy-wait until LF clock has stopped running
        Serial.println("LF clock is stopped.");
      }
    
      Serial.print("LFCLKSTAT=0x");
      Serial.print(NRF_CLOCK->LFCLKSTAT,HEX);
      Serial.print("=B");
      Serial.println(NRF_CLOCK->LFCLKSTAT,BIN);
      Serial.flush();
      
      NRF_CLOCK->LFCLKSRC=1;  //use the crystal oscillator.
      while (!(NRF_CLOCK->LFCLKSRC=1)) {}  //
    
      Serial.println("Crystal oscillator is now the LF choice.");
      Serial.print("LFCLKSTAT=0x");
      Serial.print(NRF_CLOCK->LFCLKSTAT,HEX);
      Serial.print("=B");
      Serial.println(NRF_CLOCK->LFCLKSTAT,BIN);
      Serial.flush();
     
      NRF_CLOCK->TASKS_LFCLKSTART=1;  //start the crystal oscillator clock
    
    
      
      while (!(NRF_CLOCK->EVENTS_LFCLKSTARTED)) {}  //busy-wait until the clock is confirmed started.
      Serial.println("Low Frequency crystal oscillator started.");
      Serial.flush();
    
    
      Serial.print("LFCLKSTAT=0x");
      Serial.print(NRF_CLOCK->LFCLKSTAT,HEX);
      Serial.print("=B");
      Serial.println(NRF_CLOCK->LFCLKSTAT,BIN);
      
      Serial.print("LFCLKSRC=0x");
      Serial.print(NRF_CLOCK->LFCLKSRC,HEX);
      Serial.print("=B");
      Serial.println(NRF_CLOCK->LFCLKSRC,BIN);
      
      Serial.print("Present PRESCALER=");
      Serial.println(NRF_RTC0->PRESCALER);
    
      Serial.print("LFCLKSTAT=0x");
      Serial.print(NRF_CLOCK->LFCLKSTAT,HEX);
      Serial.print("=B");
      Serial.println(NRF_CLOCK->LFCLKSTAT,BIN);
      NRF_RTC0->PRESCALER=0;  //32768 frequency
      while (NRF_RTC0->PRESCALER!=0)  {}  //busy-wait until pre-scaler changes
      Serial.print("New PRESCALER=");
      Serial.println(NRF_RTC0->PRESCALER);
    
      Serial.println();
      Serial.println("Finished setup.");
      Serial.flush();
    
      //Radio enters RXIDLE soon after COUNTER overflows.
      NRF_RTC0->CC[0] = 24;  //the time to exit RX state.
      NRF_RTC0->CC[1] = 25;  //the time to put radio to sleep from RXIDLE
      NRF_RTC0->CC[2] = 3300;  //the time to restart the cycle
    
      NRF_RTC0->EVENTS_COMPARE[0] = 0;  //Clear the event flag.
      NRF_RTC0->EVENTS_COMPARE[1] = 0;  //Clear the event flag.
      NRF_RTC0->EVENTS_COMPARE[2] = 0;  //Clear the event flag.
        
      NRF_RADIO->TASKS_DISABLE=1;  //sleep the radio
      while (NRF_RADIO->STATE) {}; //wait until radio is DISABLED (i.e. STATE=0);
    
      //Configure GPIOTE 
      NRF_GPIOTE->CONFIG[0]=0x31001;  // Toggle Event; Pin P0.16; Event Mode 
                                      //So, any pin change on P0.16 will trigger an event.
                                       //On the Nordic nRF52 DK, Pin 0.16 is a button.
                                       
      NRF_GPIOTE->CONFIG[1]=0x131203;  //Initial setting: HIGH; Toggle Task; Pin P0.18; Task Mode
                                       //On the Nordic nRF52 DK, Pin 0.18 is an LED.
                                       //Note: initial setting of HIGH means that the LED will be initially OFF.
    
      NRF_GPIOTE->CONFIG[2]=0x131103;  //Initial setting: HIGH; Toggle Task; Pin P0.17; Task Mode
                                       //On the Nordic nRF52 DK, Pin P0.17 is an LED.
                                       //Note: initial setting of HIGH means that the LED will be initially OFF.          
    
      
      //Note: radio is assumed to be sleeping by this point, and with high frequency crystal oscillator turned off.
      NRF_PPI->CH[0].EEP = (uint32_t)&NRF_RTC0->EVENTS_OVRFLW;  //when COUNTER overflows.
      NRF_PPI->CH[0].TEP = (uint32_t)&NRF_CLOCK->TASKS_HFCLKSTART;  //turn on the HF crystal oscillator
    
      NRF_PPI->CH[1].EEP = (uint32_t)&NRF_CLOCK->EVENTS_HFCLKSTARTED;  //After HF Clock started.
      NRF_PPI->CH[1].TEP = (uint32_t)&NRF_RADIO->TASKS_RXEN;  //turn on the radio receiver
      //NRF_PPI->FORK[1].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[0]; //Make pin P0.18. be HIGH
    
    
      NRF_PPI->CH[2].EEP = (uint32_t)&NRF_RADIO->EVENTS_READY;  //After event READY, radio shall be in state RXIDLE.
      NRF_PPI->CH[2].TEP = (uint32_t)&NRF_RADIO->TASKS_START;  //Move from RXIDLE mode into RX mode.
    
      NRF_PPI->CH[3].EEP = (uint32_t)&NRF_RTC0->EVENTS_COMPARE[0];  // If time to turn off the radio receiver
      NRF_PPI->CH[3].TEP = (uint32_t)&NRF_RADIO->TASKS_STOP; //Move radio from RX mode back into RXIDLE mode
      
      NRF_PPI->CH[4].EEP = (uint32_t)&NRF_RTC0->EVENTS_COMPARE[1];  // If enough time has passed
      NRF_PPI->CH[4].TEP = (uint32_t)&NRF_RADIO->TASKS_DISABLE; //Sleep the radio
      NRF_PPI->FORK[4].TEP = (uint32_t)&NRF_CLOCK->TASKS_HFCLKSTOP; //Turn off the high frequency crystal oscillator 
      
      NRF_PPI->CH[5].EEP = (uint32_t)&NRF_RTC0->EVENTS_COMPARE[2];  // If 100ms has passed
      NRF_PPI->CH[5].TEP = (uint32_t)&NRF_RTC0->TASKS_TRIGOVRFLW; //Set COUNTER so that it will overflow in 16 ticks.
    
      NRF_PPI->CH[6].EEP = (uint32_t)&NRF_RADIO->EVENTS_END;  //packet received.
      NRF_PPI->CH[6].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[1]; //Make pin P0.18. be LOW (turn on the LED).
    
      NRF_PPI->CH[7].EEP = (uint32_t)&NRF_GPIOTE->EVENTS_IN[0];  //P0.16 pin change occured.
      NRF_PPI->CH[7].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[2]; //Make pin P0.17. be LOW (turn on the LED).
      
      NRF_PPI->CHENSET=B11111111; //enable Channels 7,6,5,4,3,2,1,and 0.
      
      NRF_CLOCK->TASKS_LFCLKSTART=1;  //start the crystal oscillator clock
      
      while (!(NRF_CLOCK->EVENTS_LFCLKSTARTED)) {}  //busy-wait until the clock is confirmed started.
      Serial.println("Crystal oscillator started.");
      Serial.flush();
    
      NRF_RTC0->EVTENSET=0x70003;  //enable routing of RTC TICK, OVRFLW, and comparison events to PPI for the comparisons
      while (NRF_RTC0->EVTEN!= (0x70003)) {};  //wait until EVTENSET setting is confirmed.
      
      NRF_RTC0->EVENTS_TICK=0;  //clear TICKS flag
      NRF_RTC0->EVENTS_OVRFLW=0;  //clear overflow flag
      NRF_RADIO->EVENTS_END=0;  //clear payload received flag.
    
      NRF_CLOCK->TASKS_HFCLKSTOP=1;  //Turn off the high frequency crystal oscillator.
      NRF_RTC0->TASKS_TRIGOVRFLW=1;  //prepare COUNTER so that an overflow will ensue in 16 ticks.
      while (NRF_RTC0->COUNTER!=0xFFFFF0) {} //wait until COUNTER is primed to overflow.
      NRF_RTC0->TASKS_START=1;  //  Resume the RTC, which had been paused.
      while ((NRF_RTC0->EVENTS_TICK==0)) {}  //wait until the radio is confirmed to be started.
    }
    uint32_t loopCounter=0;
    void loop() {
    
      
      Serial.print("time=");
      Serial.print(millis());
      Serial.print(", packetCounter=");
      Serial.println(packetCounter);
      
      Serial.flush();
      
      myHwSleep(500000000);  //sleep 100ms.  Already offset in setup by 1ms from wake-up of PPI.
    }
    
    
    // * Reset events and read back on nRF52
    //* http://infocenter.nordicsemi.com/pdf/nRF52_Series_Migration_v1.0.pdf
     
    #if __CORTEX_M == 0x04
    #define NRF5_RESET_EVENT(event)                                                 \
            event = 0;                                                                   \
            (void)event
    #else
    #define NRF5_RESET_EVENT(event) event = 0
    #endif
    
    
    // This must be in one line
    extern "C" { void RADIO_IRQHandler(void) {packetCounter++; NRF5_RESET_EVENT(NRF_RADIO->EVENTS_END); NRF_RADIO->EVENTS_END=0; }}
    
    
    

    The PPI does toggle an LED each time it receives a packet, but unfortunately the CPU remains asleep. Nonetheless, it does seem to follow your prescription for the ISR.



  • @NeverDie
    What if you activate a pin change interrupt/wake at the pin the PPI toggles?
    Or connect it to another pin with pin change wake?


  • Hero Member

    @Uhrheber said in nRF5 Bluetooth action!:

    @NeverDie
    What if you activate a pin change interrupt/wake at the pin the PPI toggles?
    Or connect it to another pin with pin change wake?

    Yes, I have tested that as a workaround. It "works", but using GPIO pins increases the current drain.


  • Hero Member

    Well, I guess it's almost moot now, because I found and tested a better workaround. I re-wrote the PPI code so that after packet receipt, the PPI triggers an RTC0 overflow. It is that which is then used to wake-up the MCU. No GPIO pins need be involved, so no propagation delays and no increase in current drawn. It works.

    I still think the radio ISR code (above) should have worked, but fortunately that's no longer holding me back now that I have a good enough workaround. 🙂


  • Hero Member

    However, there's one fly in the ointment remaining. It turns out that some other timer is sometimes waking up the CPU:

    time=15798, Radio STATE=0, COUNTER=0x49, packetCounter=22
    time=15900, Radio STATE=0, COUNTER=0x49, packetCounter=23
    time=16001, Radio STATE=0, COUNTER=0x49, packetCounter=24
    time=16103, Radio STATE=0, COUNTER=0x49, packetCounter=25
    time=16204, Radio STATE=0, COUNTER=0x49, packetCounter=26
    time=16306, Radio STATE=0, COUNTER=0x49, packetCounter=27
    time=512000, Radio STATE=0, COUNTER=0x2035, packetCounter=27
    time=1024000, Radio STATE=0, COUNTER=0x269, packetCounter=27
    time=1536000, Radio STATE=0, COUNTER=0x1803, packetCounter=27
    time=2048000, Radio STATE=3, COUNTER=0x36, packetCounter=27
    time=2560000, Radio STATE=0, COUNTER=0x1570, packetCounter=27
    time=3072000, Radio STATE=0, COUNTER=0x3104, packetCounter=27
    time=3584000, Radio STATE=0, COUNTER=0x1337, packetCounter=27
    time=4096000, Radio STATE=0, COUNTER=0x2871, packetCounter=27
    time=4608000, Radio STATE=0, COUNTER=0x1104, packetCounter=27
    time=5120000, Radio STATE=0, COUNTER=0x2638, packetCounter=27
    

    All the lines labelled packetCounter=27 (after the first one that is) are a result of this. Looking at the time, they appear to happen on the rollover of some other timer (?)--apparently the one that is responsible for keeping track of millis(). I can filter them out after-the-fact, but I'd rather they not be waking up the CPU for no reason, as that is just a waste of energy.


  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:

    @d00616
    Can you see any reason as to why the radio isn't waking the MCU after it receives a packet? Here's the entire sketch:

    I have no Idea why. The code is looking fine.


  • Hero Member

    FWIW, I noticed on the oscilliscope that turning on-and-off the HFCLK ten times a second produces a fair amount of ringing. If I simply leave HFCLK turned on, most of the ringing is eliminated.

    [Edit: So, if doing this as part of an aggressive energy saving approach (for instance, turning OFF HFCLK after RX mode and later turning it on again before initiating a new RX), what sort of extra circuitry beyond the two inductors for the DCDC might be needed? I don't know that the ringing is causing any actual problems, but it doesn't look proper on a scope. For now, I'm just flagging it so that folks are aware of it as a possible issue. ]


  • Hero Member

    To better quantify the issue, I measured sleep currents (now using sleep routines that are a fork from what's in mysensors.h), and with the High Frequency clock turned OFF, the sleep current is measured at 2.2ua using a uCurrent Gold. However, the same setup, but with the High Frequency clock left ON, the sleep current is measured at 596ua using the same a uCurrent Gold.

    So, clearly, for a battery/supercap application, leaving the High Frequency clock running all the time is not an especially good option.



  • @NeverDie
    I am puzzled with your 596ua?
    I thought you were under 10ua with the mysensors sleep some time ago?
    Mine only measures 4-5ua when in sleep?


  • Hero Member

    This post is deleted!

  • Hero Member

    @rmtucker said in nRF5 Bluetooth action!:

    I am puzzled with your 596ua?
    I thought you were under 10ua with the mysensors sleep some time ago?

    There's no contradiction. It's a different scenario. The MySensors hwSleep function turns off the High Frequency oscillator when sleeping and turns it back on when it wakes up. So, it's perfectly fine for sleeping your device, having it wake up to send something, and then go back to sleep.

    The present scenario that I'm working on though is where the MCU sleeps and the PPI manages a "listen mode" where the PPI wakes up the radio once every 100ms for a roughly 200us window of time to listen for an incoming packet. Then it goes back to sleep if nothing is received. On the other hand, if a packet is received, it wakes up the MCU so that the packet can be read and dealt with. Presently I have the PPI turn off the high-frequency oscillator each time after it has finished RX in the listen-mode cycle. Before entering RX again to listen for a new packet, it first ramps up the high frequency oscillator. According to the datasheet, the high frequency crystal oscillator must be operating in order for the radio to either transmit or receive. i.e. it can't simply run off the high frequency RC oscillator the way the MCU can.

    My measurements show that while the High Frequency oscillator is running, it consumes about 596ua.



  • Did anyone managed to get two NRF52832 to connect to each other with the arduino IDE and communicate?

    Also why does I2C initializes only after an SWD programmed gets connected?

    Wierd phenomenon when I use an I2C oled display with that chip and program it with an st link V2 after it displays alright when it's booted if the SWD programmer is connected but as soon as you disconnect it everything else works but the I2C display...


  • Hero Member

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Did anyone managed to get two NRF52832 to connect to each other with the arduino IDE and communicate?

    Yes. @d00616's demo code will do this.

    I don't know the answers to the rest of your questions, because I don't use the ST.


  • Hero Member

    Here's a scopeshot of how the revised current draw looks:
    0_1506116792416_NewFile7.png
    As you can see, there is now about a 370us warm-up time at the beginning for the High Frequency oscillator to come up to speed before the RX cycle can be started. Then it takes about 100us for the receiver to warm-up to RXIDLE. From there it finally achieves about 200us of actual productive RX time. Then everything powers down until the end of the 100ms cycle, after which it all repeats again. To conserve energy, all this is managed by the PPI while the MCU sleeps.
    Scale: 1mv=1ma

    I think this is about as energy efficient as it's ever going to get, short of chipping away at the number of bits in the frame/packet size, as I indicated earlier.



  • @NeverDie said in nRF5 Bluetooth action!:

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Did anyone managed to get two NRF52832 to connect to each other with the arduino IDE and communicate?
    

    Yes. @d00616's demo code will do this.

    I don't know the answers to the rest of your questions, because I don't use the ST.

    Any idea how I reach to this code?

    Also you say you don't experience any issues with I2C like that?


  • Hero Member

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Any idea how I reach to this code?

    Yes, it's all explained in detail by @d00616 here: https://www.openhardware.io/view/376/MySensors-NRF5-Platform

    Also you say you don't experience any issues with I2C like that?

    Haven't tried I2C on this platform yet. I'd be very surprised if it didn't work though, as that's ARM Cortex M4 stuff, which is well vetted. i.e. no real dependency on anything Nordic per se.



  • @NeverDie said in nRF5 Bluetooth action!:

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Any idea how I reach to this code?

    Yes, it's all explained in detail by @d00616 here: https://www.openhardware.io/view/376/MySensors-NRF5-Platform

    Also you say you don't experience any issues with I2C like that?

    Haven't tried I2C on this platform yet. I'd be very surprised if it didn't work though, as that's ARM Cortex M4 stuff, which is well vetted. i.e. no real dependency on anything Nordic per se.

    The link you attached links me to a getting started page not wireing two nrf's together


  • Hero Member

    @Mike_Lemo said in nRF5 Bluetooth action!:

    The link you attached links me to a getting started page not wireing two nrf's together

    Your question was ambiguous. When you said "connect" I just assumed you meant wirelessly connect.

    Sorry, I can't help you. Seems like @scalz has gotten I2C to work with it though, but more likely for reading a TH sensor than for the purpose of wiring two nRF52832's. Still, that would prove that it works. If you know the I2C protocol, it shouldn't be hard to go from that to wiring two nRF52832's together.


  • Hero Member

    @NeverDie said in nRF5 Bluetooth action!:

    I think this is about as energy efficient as it's ever going to get, short of chipping away at the number of bits in the frame/packet size, as I indicated earlier.

    I also measured the current between the peaks shown in the scopeshot. By increasing the period between listens, I was able to do the measurement using a uCurrent Gold. Doing so, I found that the current drawn was 10.7ua using the Low Frequency crystal oscillator, and 11.2ua using the Low Frequency RC oscillator. I'm now sure how to square that with some of the earlier measurements I had taken with the nRF52832 sleeping using the MySensors sleep routine, as those measurements came out to about 6ua. Perhaps the difference is the extra current required to run the PPI in this configuration? With neither oscillator configured, and no PPI, it measures, as I said earlier, at 2.2ua, which is close to what the datasheet predicts.



  • @Mike_Lemo said in nRF5 Bluetooth action!:

    @NeverDie said in nRF5 Bluetooth action!:

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Any idea how I reach to this code?

    Yes, it's all explained in detail by @d00616 here: https://www.openhardware.io/view/376/MySensors-NRF5-Platform

    Also you say you don't experience any issues with I2C like that?

    Haven't tried I2C on this platform yet. I'd be very surprised if it didn't work though, as that's ARM Cortex M4 stuff, which is well vetted. i.e. no real dependency on anything Nordic per se.

    The link you attached links me to a getting started page not wireing two nrf's together

    Yes I did mean wirelessly like central and peripherial connection... Is that supported?


  • Hero Member

    I'm sorry, but I can't help you any more than I already have.


  • Hero Member

    @NeverDie said in nRF5 Bluetooth action!:

    I think this is about as energy efficient as it's ever going to get

    Epilog: I ran it overnight on a 10F capacitor, and it dropped only 0.011v per hour. I'm very happy with that, considering it's listening every 100ms as to whether or not it has received a packet. 🙂


  • Hero Member

    @d00616 Your posting says,

    At the moment on Arduino, there is no definition of various OUTPUT modes. If you want to access all nRF5 output modes, you have to use hwPinMode and the OUTPUT_... macro.

    Exactly which macro would that be? It looks to me as though what most users will want is the function nrf5_pinmode(..,..), which appears to do all the actual work. Is that right? It is defined in the file nrf5_wiring_digital.c.

    Meanwhile, hwPinMode appears to be merely a straight pass-through for pinMode:

    
    void hwPinMode(uint8_t pin, uint8_t mode)
    {
      pinMode(pin, mode);
    }
    


  • Where is it possible to find a reference schematic for using the NTF52832 E73-2G4M04S module with NFC?

    not much is being given in the datasheet not even where the NFC pins go.


  • Contest Winner

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Where is it possible to find a reference schematic for using the NTF52832 E73-2G4M04S module with NFC?
    not much is being given in the datasheet not even where the NFC pins go.

    Please look into the product documentation:
    http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/nfc.html?cp=2_1_0_41_8#concept_ryw_4hk_1s

    @NeverDie said in nRF5 Bluetooth action!:

    At the moment on Arduino, there is no definition of various OUTPUT modes. If you want to access all nRF5 output modes, you have to use hwPinMode and the OUTPUT_... macro.

    Exactly which macro would that be? It looks to me as though what most users will want is the function nrf5_pinmode(..,..), which appears to do all the actual work. Is that right? It is defined in the file nrf5_wiring_digital.c.

    hwPinMode allows to define platform specific PinMode replacements. Code may be portable. This is the reason pointing to nrf5_pinmode().

    nrf5_pinmode() has a little bit more functionality than the original pinmode function.

    Meanwhile, hwPinMode appears to be merely a straight pass-through for pinMode:

    void hwPinMode(uint8_t pin, uint8_t mode)
    {
    pinMode(pin, mode);
    }

    This disables the capability using nRF5 specific pin modes with the MySensors API.



  • @d00616 said in nRF5 Bluetooth action!:

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Where is it possible to find a reference schematic for using the NTF52832 E73-2G4M04S module with NFC?
    not much is being given in the datasheet not even where the NFC pins go.

    Please look into the product documentation:
    http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/nfc.html?cp=2_1_0_41_8#concept_ryw_4hk_1s

    @NeverDie said in nRF5 Bluetooth action!:

    At the moment on Arduino, there is no definition of various OUTPUT modes. If you want to access all nRF5 output modes, you have to use hwPinMode and the OUTPUT_... macro.

    Exactly which macro would that be? It looks to me as though what most users will want is the function nrf5_pinmode(..,..), which appears to do all the actual work. Is that right? It is defined in the file nrf5_wiring_digital.c.

    hwPinMode allows to define platform specific PinMode replacements. Code may be portable. This is the reason pointing to nrf5_pinmode().

    nrf5_pinmode() has a little bit more functionality than the original pinmode function.

    Meanwhile, hwPinMode appears to be merely a straight pass-through for pinMode:

    void hwPinMode(uint8_t pin, uint8_t mode)
    {
    pinMode(pin, mode);
    }

    This disables the capability using nRF5 specific pin modes with the MySensors API.

    I'm talking about the module it's self isn't there a reference schematic for that? I see there are some component in there but else do I have to add to make this work?


  • Hardware Contributor

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Yes I did mean wirelessly like central and peripherial connection... Is that supported?

    You're mixing things maybe. You're talking about bluetooth. that's not Mysensors 😉
    But if you want to get a connection between two nrf52832 or nrf52832/nrf24, take a look at d00616 docs.

    a nrf52 is a nrf52, no matter the module.

    So nfc pins (which are fixed) will be the same on every nrf52 you'll find. It can just happen that you get a board where those pins are used for other purpose (then you can't use nfc without little hack).

    But regarding the cdebyte modules, these are simply nrf52 with pinout. So no problem here. Just take a look at the nordic link d00616 showed about using nfc.

    In case.. pins are P0.09 and P0.10. But you'll need to tune your nfc antenna, and add capacitors. Sparkfun, adafruit have some infos on this as they're selling boards.


  • Hero Member

    Also, if you're interested in NFC, the Nordic nRF52832 DK comes with an antenna for it. It would probably be the easiest to use, because a connector for the antenna is already on the board.



  • @scalz

    Yeah but my question was about what is connected in the module and what components I have to use....

    Also about the NFC I'm planning to use it with the arduino IDE so just wanted to ask if there is a library for it because the SDK is quite useless in this case as well as the Central peripheral connection.


  • Hero Member

    I was able to reduce the active listen period to about 100us:
    0_1506303847635_NewFile3.png
    Now listening every 100ms yields a 10F supercap voltage measured decline of just 9mv per hour. i.e. a decline of 0.108v by the end of 12 hours.


  • Contest Winner

    @Mike_Lemo said in nRF5 Bluetooth action!:

    Also about the NFC I'm planning to use it with the arduino IDE so just wanted to ask if there is a library for it because the SDK is quite useless in this case as well as the Central peripheral connection.

    Now there is a second port of arduino to nRF52. This includes some libraries, like NFC, but they using the SDK. MySensors is currently not ready for this arduino-port.


  • Contest Winner

    @NeverDie said in nRF5 Bluetooth action!:

    Now listening every 100ms yields a 10F supercap voltage measured decline of just 9mv per hour. i.e. a decline of 0.108v by the end of 12 hours.

    Great job. If I'm not wrong the method allows nearly 1 year of listening time with a CR2032.



  • @Mike_Lemo your best bet is to "convert" the module to Arduino Primo and use the NFC libraries developed for it.
    d00616 gave you the link to the arduino org github. Pls. note that Primo core generates a merged softdevice+sketch hex so you should locate it in the Temp folder and upload.


  • Hero Member

    Here's a very simple OPEN/CLOSE remote control I was able to quickly throw together using my small prototyping board:
    0_1506355423385_open_close.jpg
    It required only two buttons, a diode, a resistor, and (obviously) some wire. When not in use, everything is powered 100% OFF to save the most energy possible. So, pushing either button powers it ON, at which point it rapidly determines which button was pushed and then sends the corresponding packet to the receiver. From the standpoint of human perception, it all appears to happen instantly.


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