[Logic analyser]
I don't have one, though I'm looking into
getting one to help with a 6502
home-brew project.
Do you have a simple logic probe? If you disable the LTC interrupt for the moment then the
console
port should be the only thing generating interrupts. You can see if it is asserting bus
request, if the
grant is getting back to it, if it's then trying to do an interrupt cycle, etc
-tony