Changeset 547 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/BootVars.asm

Timestamp:

Apr 21, 2013, 3:47:11 PM (11 years ago)

Author:

aitotat@…

google:author:

aitotat@gmail.com

Message:

Changes to XTIDE Universal BIOS:

• Hotkeys were incorrectly initialized to use 'C' as first hard drive letter.
• All CHS translate modes should again work (incorrectly decremented DX instead of DL, it might or might not have caused problems).

File:

• trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/BootVars.asm (modified) (1 diff)

trunk/XTIDE_Universal_BIOS/Src/VariablesAndDPTs/BootVars.asm

@@ -59 +59 @@
 ;--------------------------------------------------------------------
 BootVars_StoreDefaultDriveLettersToHotkeyVars:
-    mov     WORD [es:BOOTVARS.hotkeyVars+HOTKEYVARS.wFddAndHddLetters], DEFAULT_FLOPPY_DRIVE_LETTER | (DEFAULT_HARD_DRIVE_LETTER<<8)
+    call    BootVars_GetLetterForFirstHardDriveToAX
+    mov     ah, DEFAULT_FLOPPY_DRIVE_LETTER
+    xchg    al, ah
+    mov     [es:BOOTVARS.hotkeyVars+HOTKEYVARS.wFddAndHddLetters], ax
     ret
 
 %endif ; MODULE_HOTKEYS
+
+
+;--------------------------------------------------------------------
+; Returns letter for first hard disk. Usually it will be 'C' but it
+; can be higher if more than two floppy drives are found.
+;
+; BootVars_GetLetterForFirstHardDriveToAX
+;   Parameters:
+;       DS:     RAMVARS segment
+;   Returns:
+;       AX:     Upper case letter for first hard disk
+;   Corrupts registers:
+;       Nothing
+;--------------------------------------------------------------------
+BootVars_GetLetterForFirstHardDriveToAX:
+    call    FloppyDrive_GetCountToAX
+    add     al, DEFAULT_FLOPPY_DRIVE_LETTER     ; First Hard Drive letter comes after last floppy drive letter...
+    MAX_U   al, DEFAULT_HARD_DRIVE_LETTER       ; ...but it can never be 'A' or 'B'
+    ret