Indeed the older instruments may not have been fully compliant. The
response time of the micros in these instruments running @ 4 Mhz is
just not good enough to respond to (or even change bus states) back to
back commands from a 3 GHz processor. They may also have depended
upon one of the other forms of handshaking requiring you to test for
device ready before communicating again. The developer tester of the
time would not have encountered a problem depending on the test
methodology. Even today, a rush to market will leave untested and
non-compliant corners of device interaction. Nothing to do except
hope that you are working with a company that is responsive to your
needs. My opinion.
