I’ve added the Orange Micro Buffered Grappler+. It’s kind of like a Grappler+ and Bufferboard combined, but there are some differences. Firstly, it has no host interrupt output, so the C0nX write addresses for interrupt enable/disable aren’t implemented, and bit 7 of C0nX read returns the state of SW1-1 (forced 7-bit mode). Secondly, forced 7-bit mode isn’t implemented by pulling a data line low with the DIP switch, the ROM driver checks the switch value and clears the bit in software if necessary.

However, the microcontroller dump is bad. With 16K buffer RAM (four 6164 chips installed), it doesn’t work. The byte at 0x179 is 0xff (mov a,r7) when it should be 0xfd (mov a,r5). There could be other bad bits in the ROM as well, I don’t think there’s a way to test it.