This week I mostly worked on designing the pcb which will have ability to control the everything in PenPlotter. This new design will mount on top of the Raspberry Pi. The design is not finish yet, I still have to do Voltage level shifter converter between Raspberry Pi and Metro Mini because that both use different voltage to function.
This is the Voltage level shifter circuit that I will be using in my pcb. This circuit takes 5v from metro mini and 3.3v from Raspberry pi and change voltage accordingly to which device data going to.
