The DevTerm’s expansion connector breaks out the same 40 pins as seen on the Raspberry Pi.
I’ve been looking over the schematics to see which of these pins are free to use. However I cannot seem to find any that aren’t accounted for. The image below shows the standard 40 pins (with raspberry pi labeling) and the DevTerm usage of those pins. As you can see, if you want to use any of these pins for something else, you may be out of luck, or you may have to give up functionality somewhere.
On one hand, it’s neat to see that you can interface with the Wifi/BT chip, the audio out, and headphone detect with this cable. But if these are all used up, I’m having a hard time imagining what to do with this expansion port. It seems like the best place for additional hardware expansion is using the Ext port with a custom Ext module.
Take this info lightly! I’m not an expert, just someone combing through the schematics and trying to wrap my head around things.
Pi vs A04/06 note: For in both core module types these 40 pins are all still taken up. The only difference may be that the pin functionality (eg I2C, SPI, etc…) might be different on the A04/06.