Did the memotech roms use the ZX81 rom for its display and i/o routines or did they have their own routines?
Bill H
Memotech Roms
Re: Memotech Roms
They use their own routines.
In fact it is quite a tricky method, since a memory expansion is needed the spare 1K byte of internal memory is used to overlap the first KB in ROM, which is copied onto it and patched.
Obviously the drawing instructions are in the new ROM too.
In fact it is quite a tricky method, since a memory expansion is needed the spare 1K byte of internal memory is used to overlap the first KB in ROM, which is copied onto it and patched.
Obviously the drawing instructions are in the new ROM too.