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Messages - dr3x

1
Bus Pirate Support / Re: BPv3.6 Getting Started - how do I identify the signal in a RC car controller?
Yes we were thinking the physical controls were just pots, but when I measure the voltage and turn the wheel to the extremes the measured voltage stays at 1.34V; so I'm thinking it may be digital, some kind of rotary encoder.  So I'll try some logic analyzer software that works with BP to see if I can detect any signal coming through.  But I've never done this before so kind of flying blind.
2
Bus Pirate Support / Re: BPv3.6 Getting Started - how do I identify the signal in a RC car controller?
Initially I'm trying to tap into the signals on the controller, figure out how they work/protocols, then put in a chip like an esp32 to be able to programmatically emulate the signals coming from left/right/accelerator.  The controls might just be pots, so I'd just need to generate an analog signal.  But it could be some digital protocol.  How would I hook up the BP to analyze the signal off the controller knobs?  GND and 3.3V I think; which BP pin connects to the signal wire - would that be MOSI or ADC?

What software do you recommend? Someone recommended sigrok but I got the error below and elsewhere I read that it doesn't work with BP:
Code: [Select]
C:\Program Files (x86)\sigrok\sigrok-cli>sigrok-cli.exe --scan
sr: ftdi-la: Failed to get the FTDI strings: -4

So now I'm trying Open Bench Logic Sniffer

Eventually I'll put a chip on the car itself to control it, maybe by emulating the commands between the RF receiver and the motors but for now, controlling it through the transmitter so I can do development from a laptop.


3
Bus Pirate Support / BPv3.6 Getting Started - how do I identify the signal in a RC car controller?
Working on a project to programmatically inject commands to an RC car controller; I've opened it up (photos linked below):
https://photos.app.goo.gl/iiEfXgRKhvKzsiKk8

I think the most straightforward way is to tap into the signal wires coming off of the left/right and accelerator controls.  On the image they are the two sets red/yellow/black wires coming into connectors off the top of the PCB.

I measured the red/black voltage at 3V.  How would I use the BP to identify the signals on the yellow wires?

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