Xycom XVME-653, Manual

Page: 66 / 113

XVME-653/658 Manual
4-10
Read Configuration Dword
This function reads individual dwords from the configuration space of the VMEbus in-
terface. The Register Number parameter must be a multiple of four (i.e., bits 0 and 1
must be set to 0).
ENTRY:
[AH] BIOS_FUNCTION_ID = B1h
[AL] BIOS_SUBFUNCTION_ID = 0Ah
[BH] Bus Number (0-255)
[BL] Device Number in upper 5 bits
Function Number is bottom 3 bits
[DI] Register Number (0, 4, 8, ...252)
EXIT:
[ECX] Dword Read
[AH]
Return Code:
00h = SUCCESSFUL
87h = BAD_REGISTER_NUMBER
[CF] Completion Status, set = error, reset = success
Write Configuration Byte
This function writes individual bytes from the configuration space of the VMEbus inter-
face.
ENTRY:
[AH] BIOS_FUNCTION_ID = B1h
[AL] BIOS_SUBFUNCTION_ID = 0Bh
[BH] Bus Number (0-255)
[BL] Device Number in upper 5 bits
Function Number is bottom 3 bits
[DI] Register Number (0...255)
[CL] Byte Value to Write
EXIT:
[AH] Return Code:
00h = SUCCESSFUL
87h = BAD_REGISTER_NUMBER
[CF] Completion Status, set = error, reset = success