When I send command 0x33 (Write Settings) to a Quattro via a Mk2.2b interface, it gives a 0x80 "unknown command" response.
Commands 0x31 and 0x35 work properly.
According to the manual 0x33 should not produce any response.
I have tried sending 0x33 and 0x34 commands with no break, but the same result occurs.
Is there any particular timing that has to be observed when sending commands 0x33 and 0x34?