Everything nRF52840

[NeverDie]

You can also improve range with data whitening, though I'm not sure by how much. To enable it, substitute this line into the above code examples:

  NRF_RADIO->PCNF1 = 0x2040101;  //Means: data whitening enbled, base address is 4 bytes long (possible range is 2 to 4) and max size of payload is 1,and 1 bytes of static length payload

Then the hardware handles it automatically.

[alowhum]

@heinzv
ST electronics has the dongle for 17 euros including shipping in the Netherlands/Europe.

It's slowly getting cheaper on Aliexpress too. $25 here:
https://www.aliexpress.com/item/nRF52840-Dongle-original-genuine/32922402227.html

[NeverDie]

@heinzv said in Everything nRF52840:

The question is, how far would be a reliable indoor distance which of course includes 3+ standard walls and how much difference is it compared to the nRF52832 (is the 840 really required)?

I think the short answer is that yes, it should be able to get through 3+ standard walls. There is some directionality to these antennas, so that can be a factor. You may not succeed if you aim the trace antennas in opposite directions, for instance. Using an external omni antenna might make the setup easier.

I think some of the claimed range for the nRF52840 is from coding gains added to the 125Kbps datarate. Without doing a lot of work, you might have to use bluetooth long-range to get those ranges. Not sure though.

[heinzv]

@scalz you stopped because of what reason? And you did not want to tell why and what you're now using? It might be worth for us to know!
So far I plan to use ESP32 for most projects and trying to use the ultra low power nRF52 for battery powered devices. For the RF ranges I need to find out what is best. BLE or LoRa with RFM95 are my favorites now.
In a pure ESP environment ESPnow is also very good (we have tested it sucssfully within a 120m2 flat).
I have no better ideas so other HW devices far, but I'm always open for better ideas.

@NeverDie I'm not from Germany but from Austria :-) I'll do testing with the 15 modules I will get in the next 2 weeks. Regarding the indorr range: Of yourse I read all the statements also from Nordic. I thought you have already some practical experience.

In the battery wall sensors, I can only use a small sizes antenna and the gateway will have a better antenna.
So the typical distance in a flat is around 15m but through at least up to 3+ walls
Of course most todays flats/houses have many bluetooth and WLAN devices around.
But we need an appropriate mysensors radio/protocol library for the nRF52's. Any yes we can play around with lower data rates to extend the range based on the signal range and transmissison stability.

Looking forward to your experience and inputs.

[NeverDie]

Here's a simple sketch I wrote for the nRF52840-DONGLE that turns on, one at a time, each of the 4 programmable LED's on the dongle:

#include "mbed.h"

#define BITMASK_LED1 64 //pin P0.06
#define BITMASK_LED2R  256 //PIN P0.08
#define BITMASK_LED2G  512 //PIN P1.09
#define BITMASK_LED2B  4096 //PIN P0.12


int main() {
    NRF_P0->PIN_CNF[6]=0x701;  //Configure pin P0.6 as an output pin with high-drive '0' and disconnect '1'
    NRF_P0->PIN_CNF[8]=0x701;  //Configure pin P0.8 as an output pin with high-drive '0' and disconnect '1'
    NRF_P0->PIN_CNF[12]=0x701;  //Configure pin P0.12 as an output pin with high-drive '0' and disconnect '1'
    NRF_P1->PIN_CNF[9]=0x701;  //Configure pin P1.09 as an output pin with high-drive '0' and disconnect '1'         
    NRF_P0->DIR=BITMASK_LED1|BITMASK_LED2R|BITMASK_LED2B;  //Set LED's as output pins
    NRF_P1->DIR=BITMASK_LED2G;  //set LED2G as an output pin.
    
    while (true) {
      NRF_P0->OUT=BITMASK_LED2R|BITMASK_LED2B;  //turn-on LED1.  Turn-ff LED2R and LED2B.
      NRF_P1->OUT=BITMASK_LED2G;  //Turn off LED2G
      wait(0.5);  //wait 500ms
      NRF_P0->OUT=BITMASK_LED1|BITMASK_LED2B; //turn on LED2R and turn off LED1 and LED2B
      wait(0.5);  //wait 500ms            
      NRF_P0->OUT=BITMASK_LED1|BITMASK_LED2R;  //Turn on LED2B and turn off LED1 and LED2R.
      wait(0.5);  //wait 500ms
      NRF_P0->OUT=BITMASK_LED1|BITMASK_LED2R|BITMASK_LED2B;  //turn off LED1 and LED2R and LED2B.
      NRF_P1->OUT=0;  //Turn on LED2G
      wait(0.5);  //wait 500ms
    }
}

The dongle per se isn't supported by mbed, which is why I'm doing it purely as register manipulations. Therefore, the code is completely portable and would transfer to whatever toolchain that you're using. I guess I'll write some support functions to make doing this easier in the future.

[NeverDie]

Good news. I just noticed that Fanstel will have a couple of amplified nRF52840, called the nRF52840X or nRF52840XE. They just aren't yet in production with them. At least to me, this will likely make a big difference in my level of satisfaction. Judging from the datasheet, it will have both a PA and an LNA, so even just having it on the gateway would be a worthwhile improvement.

[heinzv]

@neverdie said in Everything nRF52840:

nRF52840XE

If BLE5 alone works sufficient, that would be great. Worst case, I will use the nRF52 with RFM95 for the battery devices and an ESP32 + RFM95 for the gateway.
The new PCB's we plan with ranseyer will cover all possible combination and provides the mySX connector.

[NeverDie]

Maybe by the time nRF52840X comes out (in 6 months to a year I'm guessing), maybe by then mbed will be fully supporting the nRF52840-DK. Or, maybe mbed never will. I need to find a tool chain different from mbed to adopt. I'm not sure whether mbed is nearly dead, slowly dying, or just slow, but I don't see a lot of activity on their forum given the vast scope of their projects. If they aren't on top of new developments,... it's just not a good sign. Also, I'm noticing that mbed comes with a large amount of code overhead (around 400Kbytes from what I've seen in my compilations on it), and although the nRF52840 can handle that and more...it seems strange given the small size of my test programs.

So, I'm open to suggestions on an alternate toolchain, provided that it's up to date with respect to nRF52840.

[heinzv]

@neverdie What speaks against platform.io with Visual Studio Code?
https://platformio.org/platforms/nordicnrf52
http://docs.platformio.org/en/latest/platforms/nordicnrf52.html (includes nRF52840 DK)
and what about that:
https://os.mbed.com/platforms/Nordic-nRF52-DK/
and that:
https://github.com/lpercifield/arduino-nRF5/tree/nrf52840

[NeverDie]

@heinzv said in Everything nRF52840:

and what about that:
https://os.mbed.com/platforms/Nordic-nRF52-DK/

The mbed compiler doesn't seem to even recognize that there are new GPIO pins on the nRF52840 that don't exist on the nRF52832. For instance, P1.00, which is one of the pins on the Fanstel nRF52840 module. Plus, I'm not sure that printf works with anything other than USB. I've tried setting it to other pins, and it just hangs. I've written some custom code to do my own sserial communications over P1_00 (to handle a PCB backward compatability issue with the nRF52840 Fanstel modules), but if mbed is only half baked, it's not helping me like it should.

Not sure about platform.io. Thanks for the lead. I'll look into it.

[heinzv]

@neverdie take a look at platform.io, it supports al known SOC's. INstall it then from the Visual Studio Code IDE. Both together are a very professional IoT dev environment (also Web and other development).
I was doing very complex development like ESPurna project build you would not like to do in the Arduino IDE.
Let me know if you need further hints.
VSC and Platform.IO includes not only all SOC HW families but also all kind of libraries you know from Arduino and it can also import Arduino project (*.INO Files).
Give it a try and you will be suprrised once you get familar.
It does also the flashing (upload), includes GIT nativly, has a command window, debugging etc etc.

https://code.visualstudio.com/
https://marketplace.visualstudio.com/items?itemName=platformio.platformio-ide
https://marketplace.visualstudio.com/search?term=platform.io&target=VSCode&category=All categories&sortBy=Relevance

Platforms: Atmel AVR, Atmel SAM, Espressif 32, Espressif 8266, Freescale Kinetis, Infineon XMC, Intel ARC32, Intel MCS-51 (8051), Lattice iCE40, Maxim 32, Microchip PIC32, Nordic nRF51, Nordic nRF52, NXP LPC, RISC-V, Samsung ARTIK, Silicon Labs EFM32, ST STM32, Teensy, TI MSP430, TI Tiva, WIZNet W7500

Frameworks: Arduino, ARTIK SDK, CMSIS, Energia, ESP-IDF, libOpenCM3, mbed, Pumbaa, Simba, SPL, STM32Cube, WiringPi

[scalz]

@heinzv platformio is nice for supporting lot of SOCs. But I think it still rely on sandeep arduino or mbed for nrf5, so, not sure if it adds stuff to the frameworks.. (regarding boards mapping, softdevices, etc). that's what NeverDie is searching I think.. an environment which allows to use all features of the SOC that he buy, ideally with myensors but we still can wait :)
regarding what you asked me previously, this is one of my reason. As missing core features is not what I'm calling fast/easy to market/production for smarter features!
That, and nrf is 2.4ghz only (area here is 9000m², few outbuildings with thick walls too), so increase of BOM&layout when using multiple modules (not a big problem for a gw, less nice for nodes). I don't want to use lora too..

[heinzv]

@scalz
That is what I found at the nordic docu for development
http://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.gs%2Fdita%2Fgs%2Fgs.html&cp=1
https://www.nordicsemi.com/eng/Products/Bluetooth-low-energy/nRF52-DK
They mention two dev environments

• nRF5 Series: Developing with SEGGER Embedded Studio
• nRF5 Series: Developing on Windows with ARM Keil MDK

Platform.IO support description for nRF52
framework-arduinonordicnrf5 Arduino Wiring-based Framework (Nordic NRF5 Core)
framework-mbed mbed Framework
tool-jlink SEGGER J-Link Software and Documentation Pack
tool-nrfjprog nRF5x command line tool
tool-openocd OpenOCD
tool-sreccat Merging tool
toolchain-gccarmnoneeabi gcc-arm-embedded

So what MCU's and radio/transmission are you using then ... ?

[NeverDie]

I don't see specific support in platformio for nRF52840. Also, it's support for nRF52 generally seems to rely on mbed:
https://github.com/platformio/platform-nordicnrf52/tree/master/examples?utm_source=platformio&utm_medium=docs

I suspect the only way to do this is to use Nordic's SDK and one of the tool chains that Nordic recognizes as working with it. I hope I can find one without a heavy learning curve. Either that or limp along with mbed, which is half baked but (so far) at least allows me to do direct registry manipulations. With mbed maybe it will turn out that the total amount of remedial code I have to write isn't huge. Not sure. I don't have much confidence in mbed's future though. I'm noticing that a lot of the posts on their forum go completely unanswered.

Nordic, on the other hand, seems much better about answering posted questions (well, 5 days a week anyway. Forget about weekends).

@heinzv We've come full circle on this. I previously posted a question on the Sandeep github as to whether it supported the nRF52840, and the answer was no, its SDK was too new, but that maybe I would have some success in programming it if I treated it like an nRF52832. https://github.com/sandeepmistry/arduino-nRF5/issues/310 Well, that's really no better than the current situation with mbed.

The only other thing on the horizon might be miropython. Not sure if micropython is fully deterministic enough for microcontroller work (e.g. might it garbage collect in the middle of a critical loop?), but maybe it's worth a shot. "Blinka & her new pal the nRF52840" https://learn.adafruit.com/circuitpython-on-the-nrf52

[heinzv]

@NeverDie have you also checked this from my previous 3 posts agao
https://github.com/lpercifield/arduino-nRF5/tree/nrf52840

this is a fork from sandeeps Arduino-NRF5 project which explicitly adds nRF52840 (that was the reason for the fork) where people have been waiting for (and probably sandeep has not announced a support soon).
See also sandeeps respons to lpercifield's work
https://github.com/sandeepmistry/arduino-nRF5/issues/70

Softdevice in this project is at S132 and Nordic newest is S140 (full BLE5 stack). Don't know why is was not yet worked into and why there is not realy a big progress since 2 years.

At least there is a project with nRF52 and LoRa (SX1276/RFM95) :-)
https://github.com/gluedig/nrf52-lora

[NeverDie]

@heinzv Thanks for pointing that out. It sounds like lpercifield encountered the exact same problems as me, except two years earlier. But, then he hasn't touched his code in the 2 years afterward. Nordic's SDK has changed since then. I'm just not sure.

I guess it's a question of whether these one person, piecemeal attempts are enough, or whether joining with a toolchain that has a lot more oomph behind it is preferable. I suspect the total amount of work involved is just too much for one person, in their spare time, to accomplish more than partial coverage. Again, not sure, but I can see what @scalz means.

I don't think Nordic has any interest in Arduino IDE support per se. If anything, it probably means a costly support burden to them without revenues to support it. Instead, Nordic is clearly targeting big commercial buyers , like phone manufacturers or the like, who will buy millions of chips just to have the latest features/capabilities. So, with nothing to pay for it on the Arduino front, except maybe a tiny bit by Adafruit or Sparkfun, it's necessarily just a bunch of individual, ad hoc efforts, or so it seems to me. Those individuals will solve whatever matters to them personally, but leaving spotty coverage on everything else. It' is admittedly better than nothing. Maybe for what I'm doing it's good enough. More than a little frustrating though.

[scalz]

@NeverDie dilemma.
maybe try: apache mynewt + plugin for visual studio code. that might pick your curiosity. I liked it when I tried. but you know.. :nerd_face:

or zephyr but I don't know much about it.
of course, these advanced toolchains are less easy to get started than arduino (setup or coding details). needs to port some arduino libs when you need it (makes sense). You won't get proprietary rf stack like MySensors out of the box too. It'll be BLE based in this case.
But you'll be able to use your mcu as you wish.

I hope you'll like it, else do like me :laughing:

[NeverDie]

You can also increase range by increasing the number of preamble bytes. Today I upgraded to using 4 preamble bytes. Beyond that it's likely diminishing returns.

To do the same on the nRF52840, use:

  NRF_RADIO->PCNF0=0x02000000;  //4 pre-amble bytes.  S0,LENGTH, and S1 are all zero bits long.

@heinzv Another factor in range is how high off the ground your radio nodes are. This can have a huge effect, due to multipath fading from the ground. According to the Fanstel datasheet, for instance, even going from half a meter off the ground to 1.5 meters off the ground can almost triple your range. So, at the very least, try to put your gateway up as high as you can.

[scalz]

@NeverDie
exactly.
with infos below, you have everything for estimating the range (maybe that can interest others people too):

• https://forum.mysensors.org/post/93384 simple but so true.
• an excellent excel sheet made by.. TI! :) where you can pick absorption materials, set height of antenna, indoor/outdoor calc etc
  http://www.ti.com/tool/RF-RANGE-ESTIMATOR
  The doc for the sheet http://www.ti.com/lit/an/swra479a/swra479a.pdf , very interesting too with comparison about selectivity/blocking etc
  or the forum thread in case https://e2e.ti.com/support/wireless_connectivity/proprietary_sub_1_ghz_simpliciti/f/156/t/375556
  works ok, here, with excel 2010 viewer (else you can't use choice lists)
  As it targets TI mcu, it's explained in docs that you can try by using an "equivalent" TI mcu, then check datasheet values for your mcu and change what's needed in the excel sheet. Maybe cc2640r2f and nrf52840 has "same" rf perf at 125kbps, no idea about blocking level.

Lot of variables, which also make a FCC module to become non-FCC when soldered on a custom board; all certified modules pass tests regarding a specific manufacturer design&usecase, they cannot certify that people won't degrade RF and emit bad stuff, thus that become non-FCC. Applicable to all RF devices though, rf laws rules (even when changing antenna for better gain, or different shape, on wifi router, it breaks certif in theory).
Like you said, better pick a good antenna sure! There are antenna which are resistant to detuning, but most of antennas like "coiled" wire, meandered pcb trace (cdebyte 52832 type), or ceramic antennas are easily detuned by pcb layout, or once it's enclosed, or close to objects (stacked boards, metals, hands etc). Then, they need to be rematched to get best range.
Good to know and interesting stuff ;)

[NeverDie]

Well, interestingly, I just now tried the BLE Long Range preamble, which is 10 reptetitions of 0x3C, and it really does seem to make a noticeable improvement in coverage/range/reliability. Obviously the extra repetitions help, but I think maybe (?) it's also partly because the 4 byte preamble is the one specified by 802.11.15, which is 4 bytes of all zeros (which is pretty weird. Never seen that as the preferred choice before. Usually preambles are alternating high low signals instead).

To set the preamble to BLE Long Range, use:

 NRF_RADIO->PCNF0=0x03000000;  //10 preamble bytes.  S0,LENGTH, and S1 are all zero bits long.

.