The PUTBYTE routine should be located at address $FED0 for the QT4 (classic).
Many thanks, Mac
Do you know if there is any special conciderations to deal with before i make a call to the routine, i guess the charater to be send should be held in Acc. (have you found this information in some docs?)
Have a look at AN1831 (Rev 3), where the code for the ROM routine RDVRRNG makes a call to PUTBYTE. I think I have also read that the H:X register value is preserved by PUTBYTE.
I have not yet done so myself, but it may not be too onorous to disassemble this code, using an actual device, to find out how the routine works.
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