The current control board is a board that holds multiple separate modules, and each module can control a stepper motor and a servo. All modules are connected through I2C. I thought this Is a cool design since it is a distributed system and each module can be custom programmed. However, as there are only 6 steppers, and the CircuitScout function is not that complex, this kind of structure introduces some problems, the host ESP32 module needs to have frequent communication with each module to check the machine's status and decide what to do next. This is not a very efficient way. If the whole machine is controlled by a single MCU board, things will get easier. So I designed a new version of the main control board.

It's an RPi Pico W + 8 A4988 module. The RP2040 is dual-core, so I can use one core for communication between the machine and the GUI, and another core used for machine control. It's basically a PicoW + an A4988 Arduino shield, but I really enjoy designing my own board :)