Very short version: Looking for a way to wirelessly get STEP and DIR signals (only those two signals) from an Arduino to a DRV8825 stepper driver about a meter away:
edit Jan. 2024: Just to follow up on this; in the end I decided to simplify the whole setup I had, and moved all electronics, except for the power supply, to the moving part. A custom slip ring connects a PSU that is on the floor to the rotating platform that holds the Arduino, steppers, etc.
Long version: For a project I've mounted an Arduino to a wooden board. The Arduino has a GRBL shield (basically a breakout board to four motor drivers for stepper motors (in my case the DRV8825)). Connected to this setup is a stepper motor. The power supply (NOT on the wooden board) for the motor is 24v, and I'm using a buck converter to take it down to 5v for the Arduino. This whole board is rotating and the 24v gets passed to it using a custom sliding-contact with two contacts (24v and gnd).
Now this all works fine, but the problem is this: I have a second motor which I want to control from the same GRBL shield. But this motor is NOT on the rotating board. If I place the motor driver next to this motor and power it from the same power supply (parallel to the sliding-contact) I have everything I need, except for the STEP and DIR signals from the Arduino.
Because there is no way I can add 2 more contacts to the sliding-contact (plus the signal would probably be too noisy anyway) I'm looking for a way to basically add a wireless bridge between the STEP and DIR output pins on the Arduino, and the STEP and DIR input pins on the motor driver. The motor and driver are about a meter away from the Arduino, so signal strength shouldn't be a problem.
I believe those well known 433Mhz transmitters are too slow for something like this, but I read most nRF24L01 modules are faster. Before I order some for a test setup, I was wondering if anyone already knows if this could work or not, knows a useful alternative, or has some suggestions for keywords to search for when trying to find another solution. I can find a lot of 'wireless' motor drivers online, but most are completely standalone units where the microcontroller is on the board, it's just controllable over wifi/bluetooth.