6502.org

Thanks for posting the schematic, I'll take a look at it. I've also been reading the data sheet for the W65C265 which I might consider using instead. It contains the 65c816 core but looks easier to use because it contains a monitor ROM, and the A16 to A23 address buss lines aren't multiplexed over the data bus.

Andrew (BitWise),

Thank you for posting the schematic. Mine is similar but I tied NMIB (pin 54), IRQ1B (pin 55), and IRQ2B (pin 56) together and pulled them up to 5v with a single 10K resistor.

How did you get away with not using handshaking which is listed as a requirement in the W65C134S Monitor ROM Reference Manual;
I'm working through the variables. My little CP2102 usb-to-serial adapter and the 12F1822 are working fine and I've verified my wiring. At this point I'm wondering if the W65C134S I have is faulty or is one of the "initial versions" mentioned in the manual which "do not support clock rates higher than the 2.4576 MHz crystal." I received the W65C134S8PL-8 as a sample in April, 1997. Anyway, I think I'll try to come up with a 2.4576 MHz clock and then perhaps wire up the 32K RAM socket.

Thanks again... Regards, Mike

Looks like my DSR pin P47 is floating at the moment, but it works for me. A wire link between your DTR and DSR pins might be needed.

My replacement monitor isn't going to have DTR/DSR handshaking as the PL2303 doesn't support it and its all software generated in the WDC code.

Found the bug in my UART driver so the random output data has gone - After much mental code simulation I realised that my zero terminated test data string was not zero terminated - and serial input is working (I can read and echo characters from a terminal program).

Now I can crack on with the serious coding.

Happy to hear you've worked through the problems and having fun with code now.

I've put my '134S project aside for now but I hope to get back to it soon.

Cheerful regards, Mike