INT 78 - TARGA.DEV - CMC International SCSI device driver - SET I/O PORT
        AH = 00h
        DX = interface board I/O port
Return: CF set on error
            AL = error code
                00h illegal command given to SCSI code
                01h invalid I/O port specified (must be from 100H to 3F8H, and
                    must be on an 8-port boundary)
                02h invalid DMA channel specified (must be from 1 to 3)
                03h invalid SCSI board number specified (must be from 0 to 7)
                04h error from data register test during self-test
                05h SCSI input signals not all 0 when SCSI RST activated
                06h SCSI input signals not all 0 before selecting a SCSI device
                07h BSY signal is active; SCSI bus is busy
                08h SCSI board not selected, BSY signal did not come on in
                    response to raising SEL
                09h time-out waiting for status state, signifying end of DMA
                    transfer
Note:   if this routine is not called, the port is the driver's default
          (usually 0280h or 0300h)
        an installation check is performed by TARGA.DEV upon initialization
          by checking for the string "SCSI" at offset 03h into the interrupt
          handler
SeeAlso: AH=02h