FDC Emulator: Read Address (Cx) Command, Status Register


Read Address (Cx) Command

The FDC read address (Cx) command has now been implemented, so the following Atari ST games on the Pompey Pirates disks now work under our modified WinSTon:

  • Batman
  • Escape from the Planet of the Robot Monsters

Status Register

It seems that lost data and DRQ bits of the FDC status register are not readable. At least, a few games have trouble if they are set properly. The FDC emulator has been changed until this can be tested properly on real hardware.

We would test it now, but our testbed Atari ST used to test WDC1772 FDC functionality no longer boots... Argh! Unforunately getting another one is not a trivial matter, since our technical labs are located in a part of the world where nobody had Atari ST’s. Getting the first one was difficult enough, and it will cost 60-70 EUR to send one there. :-(