The issue is that the CM108 chips are becoming harder to find and more expensive. There is currently 1 seller in the US on eBay with them, and they’re charging a premium price. I wanted to build a node, but why on earth would I pay more than the combined cost of the computer and radios used to run the node to get an adapter, when all of the necessary hardware is right there?
ASL needs a way to configure an alternate mechanism for COS and PTT. It shouldn’t even necessarily be GPIO specific, e.g. using serial would be useful for some people rather than GPIO or CM108.