Int 15 Fn 53B0  - Intel System Management Bus - Installation Check         [X]

   AX = 53B0h
   BH = 01h
   BL = 72h ('r')
   CX = 6164h ('ad')

Return: CF clear if installed
       AH = SMBus BIOS Interface Specification major version (01h)
       AL = SMBus BIOS Interface Specification minor version (00h)
       BL = number of SMBus devices present
       CX = 6941h ('iA')
       DX = vendor-specified SMBus hardware code
       0000h means undefined hardware type
   CF set if error
       AH = Error code 0Ah, 86h (see #0410)

Note:  this function is only supported in INT 15h mode

See Also: AX=53B0h/BH=02h,AX=53B0h/BH=03h,AX=53B0h/BH=04h,AX=53B0h/BH=06h

(Table 0410)
Values for Intel System Management Bus error codes:
 00h   SMBus OK
 01h   SMBus connect failed
 02h   SMBus already connected (see also #0411)
 03h   SMBus disconnect failed
 04h   SMBus not connected
 05h   SMBus INT 15 interface disabled
 06h   SMBus device address request out of range
 07h   SMBus unknown failure
 08h   SMBus message list empty
 09h   SMBus message list overflow
 0Ah   SMBus invalid signature
 10h   SMBus device address not acknowledged
 11h   SMBus device error detected
 12h   SMBus device command access denied
 13h   SMBus unknown error
 14h   SMBus transaction pending
 15h   SMBus no transaction pending
 16h   SMBus request does not match pending transaction
 17h   SMBus device access denied
 18h   SMBus timeout
 19h   SMBus protocol not supported
 1Ah   SMBus busy
 1Bh   SMBus SMI detected
 80h   SMBus OK (previously unreported SMI occurred)
 86h   SMBus not supported

(Table 0411)
Values for Intel System Management Bus Already Connected sub-error codes:
 01h   real mode connect already established
 02h   16-bit PMode connect already established
 03h   32-bit PMode connect already established

See Also: #0410