AZO234/NP2kai

IDE flag overview and DISKINIT.EXE behavior

Opened this issue · 1 comments

IDE flag overview

0000:0457h DA/UA 80h and 81h connection information

0000:055Dh DA/UA 80h to 83h information (upper 4bit is 640 kb I/F FDD DA/UA F0h to F3h)

0000:05BAh IDE connection information (CD-ROM is also counted) Setting with 3 IDE3 or more models that can be recognized?

F8E8:0005h Perhaps the model that can be recognized by more than three IDEs is Bit4 = 1b.

F8E8:0010h IDE connection information (CD-ROM is also counted) There is also software and drivers that also refer to this. Set with models that can be recognized more than 3 IDEs?

PC-98エミュを語ろう21
https://egg.5ch.net/test/read.cgi/software/1632474041/

DISKINIT.EXE does not work properly if the appropriate value is not set for 0000:0457H. Also, the actual machine 0000:0457H can be writable.
In the NP21 / W implementation, WINNTFIX=TRUE only sets the value to 0000:0457H when the IDE slave is not connected. Also, 0000:0457H is not writable.

This action seems to avoid problems that occur with Windows 3.1 32-bit Disk Access, but the actuation with the actual machine is different.