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Hi,
I'm building a Pypilot-Conversion of an ST2000+ tillerpilot. I use a RasPi Zero 2 with tinypilot and an Arduino nano/Pololu motorcontroller, six keys, no display. It is similar to the one that ironman built, but with an external IMU.
I would really like to have 433 MHz remote control. It would be so easy to integrate a RXB6 module and connect it to the RasPi...
Is that possible? Why does Sean use an extra Arduino for that? Is it because of the RasPi's performance? What about the performance of the RasPi Zero 2?
Olaf
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I use an external arduino because the raspberry pi did not receive all of the RF messages compared to the dedicated arduino with hardware interrupts. It also works better for IR and other things.
It may be possible that an improved driver on the pi could help mitigate this, and it may be possible that if 1 core out 4 is dedicated to RF reception it would improve enough but would then likely consume more power (watts) compared to the arduino. I would love to hear if anyone uses alternate methods for 433.
I did the same thing for motor control finding the raspberry pi's ability to make pwm motor signals too limited.
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Hi Sean, thanks for your reply.
How do this modules (RXB6, RXB12,...) work? I cant't find any datasheets. They have only one data-pin, so do they just send the received code in 1s and 0s? Any type of protocol around it? What datarate?
And on arduino there is an interrupt and you can wait until it triggers? And in RasPi there is just a GPIO and you have to poll it all the time?
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...and what about a 433MHz-RX-Module with SPI? Like the HOPERF RFM01-433 or RF SOLUTIONS ALPHA-RX433S
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I found a cheap and simple solution:
The RX480-E module. 4 channels, each of them on one pin of the module. I will connect it via a transistor to the +1, +10, -1 and -10 keys of my keyboard and that's all. The software won't even know that there's an RF module.
Anyone here, who worked with that module?
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yes its possible to use such a module, or possibly spi (if it buffers received codes)
On the raspberry pi, you could technically write a kernel module to potentially get better reception. The basic software I tested for 433 mhz on a single pin missed at least half the packets.
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It turned out to work great!
I didn't connect the module's pins to my keys as planned, but gave them their own GPIOs. I can use a remote with up to 16 keys and read the binary code of each key from the GPIO.
I used 5V to supply the module (because the range is better), so I had to use levelshifters (digital transistors) to the RasPi's GPIOs. It turned out that the range is more than enough for an 11m boat, so next time I will use 3,3V supply and skip the levelshifters.
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If the receiver decodes it to multiple GPIO sure. If you try to do the decoding on the raspberry pi using a single gpio I dont think it is reliable.
