As of now we work with the electronics of the second version. It was built up around the evaluation card STM32F0DISCOVERY from ST Microelectronics.
A card able to support powerful electrical components and few external circuits. We consider later on making it a shield to make it sronger.
- 2 stepper engines built by us and able to work with any projects requiring one (3D printer, robot,…)
- a serial communication over bluetooth adaptor to communicate with the laptop.
- a converter dc/dc 5v from the supermarket to give power to the control part.
- a first attempt of foot pedal emulation using a digital potentiometer
The two stepper engines are built around stk682 circuits from On Semiconductor (36v, 3A and a good old dissipator), which is far beyond emboidery engines need . Indeed these drivers were developed to be working with various projects in the lab and are oversized for this very project. However the price is of no significance to make it a less powerfull card.
The serial over bluetooth adaptator uses a well known circuit the HC-05 .
It’s use is very simple and is been working for over a year.
It connects to the serial port rs232 of the test card and can be set via AT control.