💬 Connecting the Radio

[scalz]

@pepson if you have been kind this year, perhaps :laughing:

[martins]

I'm having trouble with the distance between my 2 RFM69 radios. If I use this tutorial and change the frequency to 433 mhz I get distances of up to 10 meters - https://learn.adafruit.com/adafruit-rfm69hcw-and-rfm96-rfm95-rfm98-lora-packet-padio-breakouts/rfm69-test

However if I use the Mysensor libraries for the SerialGateway and the door sensor I don't even get 1 meter.
I tried to declare these variables as well but no success.

#define RFM69_FREQUENCY RF69_433MHZ
#define IS_RFM69HW

Any suggestions I might try out?

Thanks,
Martin

[pepson]

If i buy from aliexpress RFM69HW and when buy i select to seller info that i want 868MHz and on PCB RFM69HW has select/write 868MHz in sketch i must use item:
#define RFM69_FREQUENCY RF69_868MHZ ?

[martins]

@martins

Solved. This is the extra variables for the RFM69H / HW versions and to set the frequency.

#define MY_RFM69_FREQUENCY RF69_433MHZ
#define MY_IS_RFM69HW

Range is now acceptible.

Regards,
Martin

[martins]

@pepson

From library API:

MY_RFM69_FREQUENCY RF69_868MHZ For other frequency, add this define to your sketch and set it to your preferred value in RF69_433MHZ, RF69_868MHZ or RF69_915MHZ

So it seems that 868MHZ is the default value.

Regards

[pepson]

Ok thanks

[LaMB95]

I m getting symbols when I send Hello World message from Arduino Uno to an Arduino Pro Mini (5V).
Yes I have put an input of 3.3V to the pro mini.
Baud rate used is 9600.
Any clue why this is happening? I can provide the code.

[mfalkvidd]

@LaMB95 are you using a Pro Mini 5V 16MHz or Pro Mini 3.3V 8MHz?

If the wrong variant is selected in the Arduino IDE, all timings will be off, including the timings for serial communication.

[LaMB95]

@mfalkvidd

I have an arduino pro mini 5V. But I have attached a breakout CP2102 usb connection to it. On the board there is a 3.3V point which I have plugged in as Vcc to the NRF24L01+ module.

To upload the code I have selected the 5V 16Mhz as processor.

[mfalkvidd]

@LaMB95 Interesting. I have never seen a 5V Pro Mini with 3.3V output. Where did you get it?

Try different serial speeds in the serial monitor and see if you get something readable.

[flopp]

This post is deleted!

[mfalkvidd]

This post is deleted!

[tboha]

@flopp :
No, it isn't that easy.
To improve your NRF, please have a look at https://forum.mysensors.org/topic/1851/extending-range-of-regular-nrf24l01.

I tried solution Nr. 2. It is easy to do and cheap. Improvements are noticeable but not dramatically.

In regard to effort it is worth trying.

If you aimed at changing NRF's frequency - no this is not possible at all. Base frequencies are selected within the chip itself and antenna resonant frequency has to match oscillator frequency.

[LaMB95]

@mfalkvidd Haha not really a 3.3 output I changed its input voltge to 3.3 hoping it would work.

But nevertheless I managed to solve the issue.
It seems to be an error in the Hardware serial.

Refer: http://forum.arduino.cc/index.php?topic=46458.0

The code bhagman has posted worked !

[LaMB95]

@mfalkvidd

It worked yesterday now I am back to the same problem.
What a wonder !

[napo7]

Hi !

It seems that the FRM69 library set the IRQ pin as optionnal. Can someone confirm that the IRQ pin is mandatory ?

[tekka]

@napo7 yes, it is mandatory since the driver is IRQ-dependent

[napo7]

Well, I had a look in RFM69 driver, and it seems that the interrupts handlers are never sets ?
Am I wrong ?

Edit : In facts, DIO0 is not used as an Interrupt source in RFM69 driver : it's a pin that informs the library that, either, a packet has been received, or , the frame we try to send has been sent.

So, the code doesn't use interrupts, but this pin is more a "Data available" pin.

[scalz]

@napo7
so, if data available or data sent, this can be an interrupt source for an mcu ;)
It's enabled in the init there https://github.com/mysensors/MySensors/blob/development/drivers/RFM69/RFM69.cpp#L123

[napo7]

Yes I noticed it !
Since it didn't mention IRQ pin, I didn't seen it at first !

What misleaded me, is that on LowPowerLab forums, some users says that you can absolutely discard this interrupt and poll the radio frequently to ask if a packet is available.