Connecting TXD to RXD & supplying 5V to the Grove connector works great! I never thought about studying the schematic right on the device. Thanks for your assistance!
@robski At least on paper, the Inkplate devices are very similar in capabilities to the M5Paper. No reason to not being able to port the app, but hardware stability...
@ajb2k3 Thanks for the suggestion, but I already looked at that, and decided not to get it, as it's EOL and comes as a kit with a module I don't need.
The plate used in the video is perfect.
@felmue Thanks for answering!
Tried it and now I am getting always chip id 0xFF or 0x0 depended on data order in SPISettings (MSB or LSB first). Tried it with and without battery plugged in but there was no difference.
Any other ideas?