Stargazer Feather Arbitrator Design

[jamesmunns]

I am looking for assistance in designing a PCBA that is compatible with the Stargazer Backplane, a 40 pin, 0.1" header.

Design notes:

• It should be roughly equivalent to the Arbitrator V1 card used for the Stargazer
• A low profile socket for the Adafruit Feather footprint
• Connection from the Bus 3.3v pin and the Feather 3.3v pin should be jumpered or solder bridged (in case 5v power is used)
• Pins not used for the Anachro connections should have some kind of header available for use

Open Questions:

• What pins most commonly expose SPI Peripheral functionality on feathers? On the nRF52, any pin can be configured, but not all boards are like this. Do we just need to have some kind of solder bridge/jumpers available so people can connect their own pins?
• I would like some kind of connection suitable for QSPI SRAM/PSRAM/FRAM/etc. This could either be a non-populated SOIC-8 pad, a SOIC-8 DIP adapter footprint, or some kind of PMOD connector
• It might be desirable to use an external port expander, shift register, or similar to provide the 8x GO signals. This will help save pins on the Feather connector.

Edit:

I wanted to add a couple notes.

1. I'd like to be able to order these boards relatively cheaply through a service like JLCPCB or OshPark
2. I'd like these boards to be mostly through-hole compatible, so that they are easily solderable as kits, OR to be orderable fully populated (e.g. with JLCPCB's assembly service)
3. I am willing to fund the first couple hardware spins (PCBs, Components) for this. Please get confirmation from me directly BEFORE ORDERING if you would like me to pay for this or reimburse you.