Hi all, I recently got one of the Dorktronic Expansion Port breakouts (http://www.ebay.com/itm/331840785722), great way to explore the mysteries of the C64 Expansion Port. I have an Arduino wired in, triggering interrupts on falling edges on /IO1 and /IO2 incrementing simple counters (one for each). It works well, but here's an interesting mystery, that folks on cbm-hackers might appreciate. When I do a PEEK from BASIC of the IO space (i.e 57088 for IO2), I get a single falling edge on /IO2, as expected. But when I do a POKE (again from BASIC), I get *two* falling edges. This is quite repeatable. That's unexpected, any theories on why this may be? I don't have a scope unfortunately. Had a quick browse through the BASIC disassembly, nothing jumped out. Ideas? Cheers, -Leif -- Leif Bloomquist | email@example.com | +1 416-737-2328 | Check out my blog! http://www.jammingsignal.com "Every choice, no matter how small, begins a new story." - xkcd Message was sent through the cbm-hackers mailing listReceived on 2016-05-07 19:00:03
Archive generated by hypermail 2.2.0.