Changeset 28 in xtideuniversalbios for trunk/XTIDE_Universal_BIOS/Src/Handlers/Int19h.asm

Timestamp:

Aug 1, 2010, 5:57:24 PM (14 years ago)

Author:

Tomi Tilli

google:author:

aitotat

Message:

• v1.1.1 broke booting from foreign drives, it is now fixed.
• Improved error handling a bit.
• Longer DRQ and IRQ timeouts to minimize write timouts with some (bad) CF cards.
• Default boot menu drive should now be properly selected.

File:

• trunk/XTIDE_Universal_BIOS/Src/Handlers/Int19h.asm (modified) (5 diffs)

trunk/XTIDE_Universal_BIOS/Src/Handlers/Int19h.asm

@@ -2 +2 @@
 ; Project name  :   IDE BIOS
 ; Created date  :   3.8.2007
-; Last update   :   2.5.2010
+; Last update   :   1.8.2010
 ; Author        :   Tomi Tilli
 ; Description   :   Int 19h BIOS functions (Boot Strap Loader).
@@ -10 +10 @@
 
 B_READ_RETRY_TIMES  EQU 3   ; Number of times to retry
-B_READ_RETRY_DELAY  EQU 3   ; Timer ticks between retries
 
 
@@ -110 +109 @@
 ALIGN JUMP_ALIGN
 .ReadRetryLoop:
-    call    Int19h_LoadFirstSectorFromDLToESBX
+    call    .ResetBootDriveFromDL
+    call    .LoadFirstSectorFromDLtoESBX
     jnc     SHORT .Return
-    call    Int19h_ResetDriveOrWait
     dec     di                              ; Decrement retry counter
     jnz     SHORT .ReadRetryLoop            ; Loop while retries left
@@ -121 +120 @@
 
 ;--------------------------------------------------------------------
+; .ResetBootDriveFromDL
+;   Parameters:
+;       DL:     Drive to boot from (translated, 00h or 80h)
+;   Returns:
+;       AH:     INT 13h error code
+;       CF:     Cleared if read successfull
+;               Set if any error
+;   Corrupts registers:
+;       AL
+;--------------------------------------------------------------------
+ALIGN JUMP_ALIGN
+.ResetBootDriveFromDL:
+    xor     ax, ax                          ; AH=0h, Disk Controller Reset
+    test    dl, 80h                         ; Floppy drive?
+    jz      SHORT .ResetDriveFromDL         ;  If so, jump to reset
+    mov     ah, 0Dh                         ; AH=Dh, Reset Hard Disk (Alternate reset)
+.ResetDriveFromDL:
+    int     INTV_DISK_FUNC
+    ret
+
+;--------------------------------------------------------------------
 ; Reads first sector (boot sector) from drive DL to ES:BX.
 ;
-; Int19h_LoadFirstSectorFromDLToESBX
+; .LoadFirstSectorFromDLtoESBX
 ;   Parameters:
 ;       DL:     Drive to boot from (translated, 00h or 80h)
@@ -136 +156 @@
 ;--------------------------------------------------------------------
 ALIGN JUMP_ALIGN
-Int19h_LoadFirstSectorFromDLToESBX:
+.LoadFirstSectorFromDLtoESBX:
     mov     ax, 0201h                       ; Read 1 sector
     mov     cx, 1                           ; Cylinder 0, Sector 1
     xor     dh, dh                          ; Head 0
     int     INTV_DISK_FUNC
-    ret
-
-
-;--------------------------------------------------------------------
-; Reset drive controller or waits a while before retrying
-; to load boot sector.
-;
-; Int19h_ResetDriveOrWait
-;   Parameters:
-;       DL:     Drive to boot from (translated, 00h or 80h)
-;       DI:     Retry counter
-;   Returns:
-;       Nothing
-;   Corrupts registers:
-;       CX
-;--------------------------------------------------------------------
-ALIGN JUMP_ALIGN
-Int19h_ResetDriveOrWait:
-    test    di, 1<<0                        ; Reset on every other retry
-    jnz     SHORT .ResetDrive
-    mov     cx, B_READ_RETRY_DELAY          ; Wait for a while
-    jmp     SoftDelay_TimerTicks
-ALIGN JUMP_ALIGN
-.ResetDrive:
-    xor     cx, cx
-    xchg    cx, ax                          ; AH=0h, Disk Controller Reset
-    int     INTV_DISK_FUNC
-    xchg    ax, cx                          ; Restore AX
     ret