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Inside Macintosh: Devices /

Chapter 3 - SCSI Manager / SCSI Manager Reference

SCSI Manager Routines /

SCSIReset

You can use the SCSIReset function to reset all devices on the SCSI bus.

FUNCTION SCSIReset: OSErr;

DESCRIPTION

The SCSIReset function directs the SCSI controller chip (or equivalent hardware) in the Macintosh computer to assert the SCSI bus reset signal. The reset signal causes all devices on the bus to clear pending I/O and forces the bus into the bus free phase.

WARNING

The SCSIReset function interrupts SCSI communications and can cause data loss. Use this function only in exceptional circumstances.

ASSEMBLY-LANGUAGE INFORMATION

The trap macro and routine selector for SCSIReset are

Trap macro	Selector
_SCSIDispatch	$0000

RESULT CODES

noErr	0	No error
scCommErr	2	Communications error, operation timeout

SEE ALSO

See "SCSI Bus Signals," beginning on page 3-4, and "SCSI Bus Phases," beginning on page 3-5, for more information about the reset signal and the bus free phase.