SPINet has had some traces moved around and now incorporates two new I/O mapping flavors:
- simple Quadrature Decoder: PHA+PHB only (utilizes the primary UART pins, however the ACT and LNK LEDs can be disconnected and a secondary UART option is routed to these pins). That's what was possible on a 2-layer PCB in the given area.
- full Quadrature Decoder with rotation signal: PHA+PHB+IDX: (utilizes UART pins, LNK LED pin), maintains ACT pins
all options do not touch I2C and SPI I/Os.
Spot the differences ;-)
ps. via-in-pad is usually not a good idea. However we gave the PCBs a shot and found the small via ID in conjunction with stop mask on the bottom layer (which tents/plugs the vias halfway through) keeps solder wicking under control. Back-to-back caps also seem to work without a concerning amount of tombstoning. Not good practice in general but ok-ish if proven to work under real conditions.