Changeset 148 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AHCh_HSeek.asm

Timestamp:

Mar 19, 2011, 8:09:41 PM (13 years ago)

Author:

aitotat

google:author:

aitotat

Message:

Changes to XTIDE Universal BIOS:

• INT 13h optimizations to save almost 100 bytes.

File:

• trunk/XTIDE_Universal_BIOS/Src/Handlers/Int13h/AHCh_HSeek.asm (modified) (4 diffs)

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

@@ -10 +10 @@
 ; AHCh_HandlerForSeek
 ;   Parameters:
-;       AH:     Bios function Ch
+;       CX, DH: Same as in INTPACK
+;       DL:     Translated Drive number
+;       DS:DI:  Ptr to DPT (in RAMVARS segment)
+;       SS:BP:  Ptr to INTPACK
+;   Parameters on INTPACK in SS:BP:
 ;       CH:     Cylinder number, bits 7...0
 ;       CL:     Bits 7...6: Cylinder number bits 9 and 8
 ;               Bits 5...0: Starting sector number (1...63)
 ;       DH:     Starting head number (0...255)
-;       DL:     Drive number
-;   Parameters loaded by Int13h_Jump:
-;       DS:     RAMVARS segment
-;   Returns:
+;   Returns with INTPACK in SS:BP:
 ;       AH:     BIOS Error code
 ;       CF:     0 if succesfull, 1 if error
-;       IF:     1
-;   Corrupts registers:
-;       Flags
 ;--------------------------------------------------------------------
 ALIGN JUMP_ALIGN
 AHCh_HandlerForSeek:
-    push    dx
-    push    cx
-    push    bx
-    push    ax
 %ifndef USE_186
     call    AHCh_SeekToCylinder
-    jmp     Int13h_PopXRegsAndReturn
+    jmp     Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
 %else
-    push    Int13h_PopXRegsAndReturn
+    push    Int13h_ReturnFromHandlerAfterStoringErrorCodeFromAH
     ; Fall through to AHCh_SeekToCylinder
 %endif
@@ -41 +35 @@
 
 ;--------------------------------------------------------------------
-; Seeks to a cylinder.
-;
 ; AHCh_SeekToCylinder
 ;   Parameters:
@@ -49 +41 @@
 ;               Bits 5...0: Starting sector number (1...63)
 ;       DH:     Starting head number (0...255)
-;       DL:     Drive Number
-;       DS:     RAMVARS segment
+;       DS:DI:  Ptr to DPT (in RAMVARS segment)
 ;   Returns:
-;       DS:DI:  Ptr to DPT
 ;       AH:     BIOS Error code
 ;       CF:     0 if succesfull, 1 if error
@@ -58 +48 @@
 ;       AL, BX, CX, DX
 ;--------------------------------------------------------------------
-ALIGN JUMP_ALIGN
 AHCh_SeekToCylinder:
-    call    FindDPT_ForDriveNumber      ; DS:DI now points to DPT
     mov     ax, HCMD_SEEK<<8            ; Load cmd to AH, AL=zero sector cnt
     call    HCommand_OutputCountAndLCHSandCommand
-    jc      SHORT .Return               ; Return if error
+    jc      SHORT .ReturnWithErrorCodeInAH
     mov     bx, di                      ; DS:BX now points to DPT
     jmp     HStatus_WaitIrqOrRdy        ; Wait for IRQ or RDY
-.Return:
+.ReturnWithErrorCodeInAH:
     ret