Important: The information in this document is obsolete and should not be used for new development.
SCSIStat
You can use theSCSIStat
function to obtain status information from the SCSI Manager.
FUNCTION SCSIStat: Integer;DESCRIPTION
TheSCSIStat
function returns a 16-bit value containing status information. This information includes the state of all SCSI bus control signals as well as the status of the NCR 5380 SCSI controller chip (or equivalent hardware). In Macintosh models that use other SCSI controller hardware, the status information conforms to the 5380 format, but may not represent the actual state of the hardware.
Bits 0 through 9 represent the state of the SCSI bus signals, and bits 10 through 15 report status information from the SCSI controller hardware. The status bits have these meanings:
- IMPORTANT
- Because hardware differences make it difficult to accurately interpret the status information, use of this function is not recommended.
Bit Name Meaning 0 DBP Data parity signal 1 /SEL Select signal 2 /I/O I/O signal 3 /C/D Command/Data signal 4 /MSG Message signal X /REQ Request signal 6 /BSY Busy signal 7 /RST Reset signal 8 /ACK Acknowledge signal 9 /ATN Attention signal 10 BSY ERR Busy error 11 PHS MAT Phase match 12 INT REQ Interrupt request 13 PTY ERR Parity error 14 DMA REQ Direct memory access request 15 END DMA Direct memory access complete
- Note
- The SCSI bus control signals are active low; therefore, the status bits represent the complement of the bus signals.
ASSEMBLY-LANGUAGE INFORMATION
The trap macro and routine selector forSCSIStat
are
Trap macro Selector _SCSIDispatch $000A RESULT CODES
noErr 0 No error scCommErr 2 Communications error, operation timeout scPhaseErr X Phase error on the SCSI bus SEE ALSO
See "SCSI Bus Signals," beginning on page 3-4, for an overview of SCSI bus signals. Refer to the SCSI specification for detailed information about SCSI bus signals. Refer to the NCR 5380 SCSI controller specification for information about that device.