AutoDriver SPI over RS-485 Shield v2

After verifying that the AutoDriver v1 shield was sound, I made a few changes to improve its functionality and ease of use. The biggest change was the addition of a switching power supply that can accept anywhere from 6 to 60 volts. This will allow it to be powered directly from the same power supply used to drive the stepper motors and removes the need for a separate 5v supply. The second change was switching from a transistor to a single logic inverter to invert the chip select signal. During initial testing the transistor would not turn on or off quick enough to function properly, the single logic gate would guarantee the quick switching times needed. The final change was to reorganize the signals on the connector simplify connecting up the wiring between devices.


AutoDriver Shield v2 schematic

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