Thanks to the files you kindky uploaded, I was able to run BASIC on my system. Since the monitor (John's monitor patched to run with the SIO) is stored in a 2732 in the F000-FFFF space, i changed the ORG statements to start the code at B000 (to leave lots of space to John's monitor stack, I think I could locate at C800 with no problem but it was really to make a first test). Apart from the ORG change, no significant changes : I obviously asembled it with the SCC driver, I removed the RAMcheck portion considering my specific setup, and now I am proud to see the BASIC prompt afer downloading the code in XMODEM using the monitor !
For some reason, the monitor was froaen after the XMODEM transfer completion, I was getting the prompt but could not enter a command. Probably a handshake problem, I added a SCC_INIT call just before returning to the main monitor loop, rather brute force but it now works great.
One minor issue though I have to investigate : a RUN gives systematically a syntax error, even is this is a one-line program with a REM... To run a program, I have to insert a dummy/REM line before the entry line and RUN that entry line explicitely (eg. RUN 10 if there is a dummy line say at 5).souonds like a pointer pb created by my mods...
Thanks again for your work, I am so happy to see BASIC running on my new toy !