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Removed the Disk][ f/w patch (track stepping delay) in all disk modes

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This commit is contained in:
tomch 2009-02-01 10:33:37 +00:00
parent 7ee8d10fd5
commit 21ee03a9f7
1 changed files with 5 additions and 13 deletions

18
AppleWin/source/Disk.cpp

@ -759,19 +759,11 @@ void DiskLoadRom(LPBYTE pCxRomPeripheral, UINT uSlot)
memcpy(pCxRomPeripheral + uSlot*APPLE_SLOT_SIZE, pData, DISK2_FW_SIZE);
if (enhancedisk)
{
// Disable the track stepping delay in the Disk II controller firmware
*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4C) = 0xA9;
*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4D) = 0x00;
*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4E) = 0xEA;
// The following maintains the firmware's ADC checksum (used by "The CIA Files")
// Correcting for both ADC and EOR checksums is not possible in this case.
*(pCxRomPeripheral + (uSlot*APPLE_SLOT_SIZE) + 0x4B) = 0x87; // was 0x56
}
//
// NB. We used to disable the track stepping delay in the Disk II controller firmware by
// patching $C64C with $A9,$00,$EA. Now not doing this since:
// . Authentic Speed should be authentic
// . Enhanced Speed runs emulation unthrottled, so removing the delay has negligible effect
// . Patching the f/w breaks the ADC & EOR checksums used by "The CIA Files" (Tricy Dick)
RegisterIoHandler(uSlot, Disk_IORead, Disk_IOWrite, NULL, NULL, NULL, NULL);
}