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AX = 4E01h DX = XGA handle (0 to number of XGAs-1) ES:DI -> 256-byte buffer for subsystem information (see #00071)
Return:
AL = 4Eh if function supported AH = status 00h function successful else error code
Format of XGA subsystem information: Offset Size Description (Table 00071) 00h DWORD pointer to null-terminated board OEM string 04h DWORD capabilities (see #00072) 08h DWORD pointer to 8KB XGA ROM (or NULL) 0Ch DWORD pointer to the XGA memory mapped registers 10h WORD base address of XGA I/O registers (21x0h) 12h DWORD pointer to start of physical video memory (A000h:0000h or B000h:0000h) 16h DWORD physical address of 4MB aperture (or NULL if none) 1Ah DWORD physical address of 1MB aperture (or NULL if none) 1Eh DWORD physical address of 64KB aperture (or NULL if not enabled) 22h DWORD physical address of OEM aperture (or NULL if none) 26h WORD size of OEM aperture in 64KByte units 28h DWORD pointer to list of video modes The list is a series of WORDs terminated by FFFFh 2Ch WORD number of 64KB blocks on the board 2Eh DWORD XGA manufacturer ID byte 0 POS data index 1 byte 1 is index 2 byte 2 is 21xAh index 75h 32h 206 BYTEs reserved
Bitfields for XGA capabilities: Bit(s) Description (Table 00072)
0-1 board bus architecture:
0=MCA, 1=ISA, 3=EISA 2-3 reserved 4-6 DMA Channel assigned for acquiring bus mastership (only for ISA bus) 7 DMA Channel Status (ISA only). enabled if set 8-31 reserved
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