cem@Ucb-Vax.ARPA (10/30/84)
This is a warning for all users of Turbo Pascal who also are doing BIOS stuff. As you may know Turbo does most of its I/O through the BIOS and skips the BDOS, this is not a problem for the most part and Turbo does not overwrite the BDOS, however it does expect that the Z80 "extra" registers are UNCHANGED when the BIOS function returns. That means that your BIOS must save IX,IY,AF'-HL' and restore them if it uses them in the BIOS! Sometimes you can get away with it other times your Turbo program will unexpectedly exit or Hang. Borland does not forsee fixing this "feature" but they may mention it in the next edition of the manual. Argh! --Chuck