Changeset 150 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH15h_HSize.asm

Timestamp:

Apr 29, 2011, 7:04:13 PM (13 years ago)

Author:

aitotat

google:author:

aitotat

Message:

Changes to XTIDE Universal BIOS:

• Redesigned Disk Parameter Tables.
• Code generalizations for supporting non-IDE devices in the future.

File:

• trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH15h_HSize.asm (modified) (2 diffs)

trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AH15h_HSize.asm

@@ -12 +12 @@
 ;       DL:     Translated Drive number
 ;       DS:DI:  Ptr to DPT (in RAMVARS segment)
-;       SS:BP:  Ptr to INTPACK
-;   Returns with INTPACK in SS:BP:
+;       SS:BP:  Ptr to IDEPACK
+;   Returns with INTPACK:
 ;       If succesfull:
 ;           AH:     3 (Hard disk accessible)
@@ -25 +25 @@
 ALIGN JUMP_ALIGN
 AH15h_HandlerForReadDiskDriveSize:
-    call    HCapacity_GetSectorCountFromOurAH08h        ; Sector count to DX:AX
-    mov     [bp+INTPACK.cx], dx                         ; HIWORD to CX
-    mov     [bp+INTPACK.dx], ax                         ; LOWORD to DX
+    call    AH15h_GetSectorCountToDXAX
+    mov     [bp+IDEPACK.intpack+INTPACK.cx], dx         ; HIWORD to CX
+    mov     [bp+IDEPACK.intpack+INTPACK.dx], ax         ; LOWORD to DX
 
     xor     ah, ah
-    call    HError_SetErrorCodeToIntpackInSSBPfromAH    ; Store success to BDA and CF
-    mov     BYTE [bp+INTPACK.ah], 3                     ; Type code = Hard disk
+    call    Int13h_SetErrorCodeToIntpackInSSBPfromAH    ; Store success to BDA and CF
+    mov     BYTE [bp+IDEPACK.intpack+INTPACK.ah], 3     ; Type code = Hard disk
     jmp     Int13h_ReturnFromHandlerWithoutStoringErrorCode
+
+
+;--------------------------------------------------------------------
+; AH15h_GetSectorCountFromForeignDriveToDXAX:
+; AH15h_GetSectorCountToDXAX:
+;   Parameters:
+;       DL:     Drive number
+;       DS:     RAMVARS segment
+;       DS:DI:  Ptr to DPT (AH15h_GetSectorCount only)
+;   Returns:
+;       DX:AX:  Total sector count
+;       BX:     Zero
+;   Corrupts registers:
+;       CX
+;--------------------------------------------------------------------
+AH15h_GetSectorCountFromForeignDriveToDXAX:
+    mov     ah, GET_DRIVE_PARAMETERS
+    call    Int13h_CallPreviousInt13hHandler
+    jmp     SHORT ConvertAH08hReturnValuesToSectorCount
+
+ALIGN JUMP_ALIGN
+AH15h_GetSectorCountToDXAX:
+    call    AH8h_GetDriveParameters
+    ; Fall to ConvertAH08hReturnValuesToSectorCount
+
+ConvertAH08hReturnValuesToSectorCount:
+    call    HAddress_ExtractLCHSparametersFromOldInt13hAddress
+    xor     ax, ax          ; Zero AX
+    inc     cx              ; Max cylinder number to cylinder count
+    xchg    al, bh          ; AX=Max head number, BX=Sectors per track
+    inc     ax              ; AX=Head count
+    mul     bx              ; AX=Head count * Sectors per track
+    mul     cx              ; DX:AX = Total sector count
+    xor     bx, bx          ; Zero BX for 48-bit sector count (and clear CF)
+    ret