findg4.asm

用来将电脑连接到电视荧幕, 并以15Khz输出的源码, 请只用在支援15Khz的荧幕上, 以免伤害荧幕

IDEAL
P386
SMART

MODEL COMPACT,C

GLOBAL C findg400:NEAR

GLOBAL C get_pm_table_offset:NEAR
GLOBAL C get_pm_table_segment:NEAR
GLOBAL C get_pm_table_length:NEAR
GLOBAL C own_pm_interface_supported:NEAR
GLOBAL C G400_outb:NEAR
GLOBAL C G400_inb:NEAR

DATASEG
device_bus_number   dd  0


CODESEG

PROC findg400 NEAR
        mov     eax,0b101h
        mov     edi,0
        int     01ah

        cmp     edx,20494350h
        jne     notfound

        mov     eax,0b102h
        mov     ecx,00525h
        mov     edx,0102Bh
        mov     esi,0
        int     01ah
        or      ah,ah
        jz      found_g400


        jmp     notfound

found_g400:
        mov     [dword ptr device_bus_number], ebx
        mov     eax, 1
        ret
notfound:
        xor     ax,ax
        ret
ENDP


PROC own_pm_interface_supported NEAR
        mov     ax, 0
        ret
ENDP

PROC get_pm_table_offset NEAR
        mov     ax, 0
        ret
ENDP

PROC get_pm_table_segment NEAR
        mov     ax, 0
        ret
ENDP

PROC get_pm_table_length NEAR
        mov     ax, 0
        ret
ENDP



PROC G400_outb NEAR
    push    bp
    mov     bp, sp
    mov     eax, [dword ptr bp+4]
    and     eax, 03FFCh
    mov     ecx, eax                ; G400 index
    mov     eax, 0B10Dh             ; WRITE DWORD
    mov     edi, 00044h             ; register number
    mov     ebx, [dword ptr device_bus_number]
    int     01Ah

    mov     eax, [dword ptr bp+4]
    and     eax, 00003h
    mov     edi, 00048h
    add     edi, eax                ; register number
    xor     ecx, ecx
    mov     cl, [byte ptr bp+8]     ; G400 data
    mov     eax, 0B10Bh             ; WRITE BYTE
    mov     ebx, [dword ptr device_bus_number]
    int     01Ah
    pop     bp
    ret
ENDP



PROC G400_inb NEAR
    push    bp
    mov     bp, sp
    mov     eax, [dword ptr bp+4]
    and     eax, 03FFCh
    mov     ecx, eax                ; G400 index
    mov     eax, 0B10Dh             ; WRITE DWORD
    mov     edi, 00044h             ; register number
    mov     ebx, [dword ptr device_bus_number]
    int     01Ah

    mov     eax, [dword ptr bp+4]
    and     eax, 00003h
    mov     edi, 00048h
    add     edi, eax                ; register number
    mov     eax, 0B108h             ; READ BYTE
    mov     ebx, [dword ptr device_bus_number]
    int     01Ah
    xor     eax, eax
    mov     al, cl
    pop     bp
    ret
ENDP



END