The changes I made are mostly in the 32u4 file but there are supporting changes in AR488.ino and updates to match in mega and uno.
In 32u4 I've started using attachInterrupt to reduce the number of hardware-specifics but I haven't applied this to the others yet. However, I think it's probably possible to get the interrupt handling out of the hardware-specific files using this method.
I've only tested this on SRQ so far, not ATN.
The changes I made are mostly in the 32u4 file but there are supporting changes in AR488.ino and updates to match in mega and uno.
In 32u4 I've started using attachInterrupt to reduce the number of hardware-specifics but I haven't applied this to the others yet. However, I think it's probably possible to get the interrupt handling out of the hardware-specific files using this method.