I’ll hazard a guess that the Gaups folks will realize quickly that they are uniquely positioned to serve the 4 motor DUE users and make the 5V to 3.3V transition easier in the near future.
I am the “GAUPS folks”, and yes, I realized my mistake a while back. GAUPS 1.1 will use IOREF, as it should have from the beginning.
I think it’s safe to sink 100 µA into the ESD protection diode on Due’s D8 pin. Compared to the 5 V to 3.3 V “level conversion” I’ve seen on some Chinese boards (SD card adapter: 1 kΩ series resistors…), the 10 kΩ pull-up on the GAUPS 1.0, while technically wrong, is almost certainly harmless. So the GAUPS 1.0 can be used with DRV8825 drivers on the Due.
