Quote:
Originally Posted by SiriusHardware
One non-canonical way to go around this would be to map something like a 74LS573 (8 bit latch) onto the final address in the memory hole (07FF) replacing one byte of RAM, and use the outputs of that to control the VDU functions. Literally as cheap as chips, unlike the antique LSI ICs.
|
You could also decode the address for writing to the 8154 to select the write to a ‘573 or ‘273 (which has a reset input but not tristate). This could then be software compatible with someone using an 8154. 74hct series might be better to avoid additional bus loading, not very retro but neither is the PIC.
Did you both (Tim and Sirius), mount the 47 pf capacitors in the same location?