Serial data radio communication modules
- Thread starter Tvmender
- Start date
Aries
New Member
I use the NRF24L01 - very cheap, reasonable range (although the range is a lot smaller in my house, where the walls seem to attenuate the signals quite heavily). Sparkfun used to sell it, and there is still documentation associated with it here ...
https://learn.sparkfun.com/tutorial...-hookup-guide/all#resources-and-going-further and there's a detailed tutorial on it here ...
Also the CC1101 which I had to use for the water meter reader here ...
https://picaxeforum.co.uk/threads/itron-everblu-cyble-water-meter-reader.33027/ which also has the code for TX and RX (admittdly for communicating with a water meter, but it's a start).
https://learn.sparkfun.com/tutorial...-hookup-guide/all#resources-and-going-further and there's a detailed tutorial on it here ...
Also the CC1101 which I had to use for the water meter reader here ...
https://picaxeforum.co.uk/threads/itron-everblu-cyble-water-meter-reader.33027/ which also has the code for TX and RX (admittdly for communicating with a water meter, but it's a start).
Hi,
It depends how much data you want to send and/or receive and the carrier frequency, etc., but there might still be some mileage in "fixed" off-the-shelf 433 MHz modules (such as RXB6), particularly to penetrate thick walls. But NOT the horrible "Super-regenerative" type receivers, nor probably a SWIF-tuned (Surface-Wave-Filter usually in a TO5 "top hat" metal can) type transmitter. There are various, typically 4-pin, modules, usually carrying a small 16 or 8-pin dedicated IC, often requiring only a 3-volt supply rail; Look for the keyword "Superhet{erodyne}".
For 8-byte blocks of data, the RFOUT and RFIN commands available in most PICaxes are ideal, or the embedded (or added) Infra-Red Remote Control commands can be used to send a few bytes. Or PICaxe Basic can be just fast enough to bit-bang a custom protocol if necessary (I have posted a few relevant code snippets and am planning a few more soon).
Alternatively, there are several "programmable" RF modules available, particularly for the 868 MHz band and/or for bi-directional communications, such as the RFM96 or CC1101. But these do need to be "configured", usually via an SPI Bus, which is "supported" (in X2s) but IMHO is not one of PICaxe's strengths; An I2C Bus interface could be so much easier! However, the chip might include a data detector/buffer (hardware option), obviating the need for any custom or time-critical bit-banging in the PICaxe program.
Cheers, Alan.
It depends how much data you want to send and/or receive and the carrier frequency, etc., but there might still be some mileage in "fixed" off-the-shelf 433 MHz modules (such as RXB6), particularly to penetrate thick walls. But NOT the horrible "Super-regenerative" type receivers, nor probably a SWIF-tuned (Surface-Wave-Filter usually in a TO5 "top hat" metal can) type transmitter. There are various, typically 4-pin, modules, usually carrying a small 16 or 8-pin dedicated IC, often requiring only a 3-volt supply rail; Look for the keyword "Superhet{erodyne}".
For 8-byte blocks of data, the RFOUT and RFIN commands available in most PICaxes are ideal, or the embedded (or added) Infra-Red Remote Control commands can be used to send a few bytes. Or PICaxe Basic can be just fast enough to bit-bang a custom protocol if necessary (I have posted a few relevant code snippets and am planning a few more soon).
Alternatively, there are several "programmable" RF modules available, particularly for the 868 MHz band and/or for bi-directional communications, such as the RFM96 or CC1101. But these do need to be "configured", usually via an SPI Bus, which is "supported" (in X2s) but IMHO is not one of PICaxe's strengths; An I2C Bus interface could be so much easier! However, the chip might include a data detector/buffer (hardware option), obviating the need for any custom or time-critical bit-banging in the PICaxe program.
Cheers, Alan.
Last edited:
inglewoodpete
Senior Member
I've had success with HC-12s. They seem to be one of the more reliable wireless modules. You should find several threads on this forum. However the PICAXE forum's search function is pretty useless for this sort of search so, using Google, try site
icaxeforum.co.uk "HC-12" ~sigh~ And that emojy is actually a colon ':' followed by a 'p'!!
icaxeforum.co.uk "HC-12" ~sigh~ And that emojy is actually a colon ':' followed by a 'p'!!
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Hi,
Hmm, that search appears to have missed the "classic" thread by Jeremy Harris HERE, probably because of the missing/ignored hyphen. Many technical details (over the 236 posts !) including the issue of "Fakes". The forum's rejection of 3-character acronyms (let alone the two character pairs in HC-12) is an utter pain, making items such as PWM, AGC, I2C, DAC, ADC, DAB, NEC, NXP, etc. and of course PIC unsearchable within the forum.
I must admit that I'd "forgotten" the very capable and versatile HC-12, perhaps because I've been trying to move to the less congested 868 MHz ("European") band, rather than the much used (and abused) 433/434 MHz band. 2.4 GHz (Wi-Fi, Bluetooth, etc.) will of course struggle with walls (particularly if they're wet).
Cheers, Alan.
Hmm, that search appears to have missed the "classic" thread by Jeremy Harris HERE, probably because of the missing/ignored hyphen. Many technical details (over the 236 posts !) including the issue of "Fakes". The forum's rejection of 3-character acronyms (let alone the two character pairs in HC-12) is an utter pain, making items such as PWM, AGC, I2C, DAC, ADC, DAB, NEC, NXP, etc. and of course PIC unsearchable within the forum.
I must admit that I'd "forgotten" the very capable and versatile HC-12, perhaps because I've been trying to move to the less congested 868 MHz ("European") band, rather than the much used (and abused) 433/434 MHz band. 2.4 GHz (Wi-Fi, Bluetooth, etc.) will of course struggle with walls (particularly if they're wet).
Cheers, Alan.
Tvmender
Well-known member
I will take a look, many thanks!