Add INT13h handling for SD Card.

XTMax/Drivers/BootROM/.gitignore

@@ -1,2 +1,3 @@
 bootrom
 bootrom.com
+*.exe

XTMax/Drivers/BootROM/build.cmd

@@ -1,2 +1,2 @@
-..\Driver_Build_Tools\NASM\nasm.exe -f bin -o bootrom.com -DAS_COM .\bootrom.asm
+..\Driver_Build_Tools\NASM\nasm.exe -f bin -o bootrom.com -DAS_COM_PROGRAM .\bootrom.asm
 ..\Driver_Build_Tools\NASM\nasm.exe -f bin -o bootrom .\bootrom.asm & python checksum.py

XTMax/Drivers/BootROM/tests.inc

@@ -0,0 +1,168 @@
+;
+; This is test code invoked when building with AS_COM
+;
+
+;%define REAL_INT13
+%define DUMP_REGS
+
+
+    xor ax, ax
+    lahf
+    mov ax, 0x1122
+    mov bx, 0x3344
+    mov cx, 0x5566
+    mov dx, 0x7788
+    mov si, 0x99aa
+    mov di, 0xbbcc
+    mov bp, 0xddee
+
+    mov dl, 0x80
+    mov ah, 0x08
+
+    ;mov bx, buf_write
+    ;mov ch, 0
+    ;mov cl, 1
+    ;mov dh, 0
+    ;mov al, 1
+
+    call do_int13h
+
+    mov dl, 0x80
+    mov ah, 0x02
+
+    mov bx, ds
+    mov es, bx
+    mov bx, buf_read
+    mov ch, 0
+    mov cl, 1
+    mov dh, 0
+    mov al, 1
+
+    call do_int13h
+
+%if 1
+    mov cx, 256
+    mov si, buf_read
+.dump:
+    lodsw
+    call print_hex
+    mov ax, space
+    call print_string
+    loop .dump
+    mov ax, newline
+    call print_string
+
+    ; wait for kbd
+    mov ah, 0x01
+    int 0x21
+%endif
+
+    mov ah, 0x01
+    call do_int13h
+    mov ah, 0x01
+    call do_int13h
+
+    ;mov ax, newline
+    ;call print_string
+    ;mov ch, 255
+    ;mov cl, 255
+    ;mov dh, NUM_HEADS-1
+    ;call compute_lba
+    ;push ax
+    ;mov ax, bx
+    ;call print_hex
+    ;pop ax
+    ;call print_hex
+    ;mov ax, newline
+    ;call print_string
+
+    jmp end
+
+do_int13h:
+%ifdef DUMP_REGS
+    call dump_regs
+%endif
+
+    pushf               ; save flags (to compare)
+%ifndef REAL_INT13
+    ; simulate vector call
+    pushf
+    push cs
+    call int13h_entry
+%else
+    int 0x13
+%endif
+    pushf               ; save flags (to compare)
+    push ax
+    jnc .success
+.error:
+    mov ax, test_failed_msg
+    call print_string
+    jmp .finish
+.success:
+    mov ax, test_success_msg
+    call print_string
+.finish:
+    pop ax
+    push ax
+    mov al, ah
+    xor ah, ah
+    call print_hex
+    mov ax, newline
+    call print_string
+    pop ax
+
+    ; dump registers
+%ifdef DUMP_REGS
+    call dump_regs
+    pop ax
+    call print_hex
+    mov ax, colon
+    call print_string
+    pop ax
+    call print_hex
+    mov ax, newline
+    call print_string
+%else
+    popf
+    popf
+%endif
+
+    ; wait for kbd
+    mov ah, 0x01
+    int 0x21
+    ret
+
+;
+; A fake INT13h handler to test redirection of floppy service
+;
+fake_int13h_entry:
+    push ax
+    mov ax, fake_handler_msg
+    call print_string
+    pop ax
+    push ax
+    mov al, ah
+    xor ah, ah
+    call print_hex
+    mov ax, newline
+    call print_string
+    pop ax
+    mov ah, 0xaa
+    push bp
+    mov bp, sp
+    or byte [bp+6], 0x1     ; set carry of flags for iret
+    pop bp
+    iret
+
+buf_write           db 1, 2, 3, 4, 5, 6, 7, 8
+                    times 496 db 0
+                    db 248, 249, 250, 251, 252, 253, 254, 255
+                    times 512 db 0
+buf_read            times 1024 db 0
+
+fake_handler_msg    db 'BIOS INT13h Function ', 0
+test_success_msg    db 'Call succeeded ', 0
+test_failed_msg     db 'Call failed ', 0
+
+end:

XTMax/Drivers/BootROM/utils.inc

@@ -0,0 +1,139 @@
+;
+; Display a string.
+; in:  AX = string pointer
+; out: AX = <TRASH>
+;
+print_string:
+    pushf
+    push ds
+    push bx
+    push si
+    mov si, ax
+%ifndef AS_COM_PROGRAM
+    mov ax, ROM_SEGMENT
+    mov ds, ax
+%endif
+    mov ah, 0xe
+    xor bx, bx
+    cld
+.loop:
+    lodsb
+    or al, al
+    jz .done
+    int 0x10
+    jmp .loop
+.done:
+    pop si
+    pop bx
+    pop ds
+    popf
+    ret
+
+;
+; Display a 16-bit value in hex.
+; in:  AX = value
+; out: AX = <TRASH>
+;
+print_hex:
+    pushf
+    push ds
+    push bx
+    push cx
+    push dx
+    push si
+    mov dx, ax
+%ifndef AS_COM_PROGRAM
+    mov ax, ROM_SEGMENT
+    mov ds, ax
+%endif
+    xor bx, bx
+    cld
+.nibble1:
+    mov si, dx
+    mov cl, 12
+    shr si, cl
+    and si, 0xf
+    mov al, [hex_map+si]
+    mov ah, 0xe
+    int 0x10
+.nibble2:
+    mov si, dx
+    mov cl, 8
+    shr si, cl
+    and si, 0xf
+    mov al, [hex_map+si]
+    mov ah, 0xe
+    int 0x10
+.nibble3:
+    mov si, dx
+    mov cl, 4
+    shr si, cl
+    and si, 0xf
+    mov al, [hex_map+si]
+    mov ah, 0xe
+    int 0x10
+.nibble4:
+    mov si, dx
+    and si, 0xf
+    mov al, [hex_map+si]
+    mov ah, 0xe
+    int 0x10
+    pop si
+    pop dx
+    pop cx
+    pop bx
+    pop ds
+    popf
+    ret
+
+hex_map db '0123456789ABCDEF'
+
+%if %isdef(EXTRA_DEBUG) || %isdef(AS_COM_PROGRAM)
+dump_regs:
+    push ax
+    mov ax, registers_msg
+    call print_string
+    pop ax
+    push ax
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, bx
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, cx
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, dx
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, ds
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, si
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, es
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, di
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, bp
+    call print_hex
+    mov ax, space
+    call print_string
+    mov ax, newline
+    call print_string
+    pop ax
+    ret
+
+registers_msg   db ' AX   BX   CX   DX   DS   SI   ES   DI   BP', 0xD, 0xA, 0
+%endif