BSP Developer's Guide

I
Writing a SCSI-2 Device Driver
*/
LOCAL STATUS xxxWideXferParamsSet
(
SCSI_CTRL *pScsiCtrl, /* ptr to controller info */
UINT8 xferWidth /* wide data transfer width */
)
{
}
Example I-3
Template: Advanced I/O Processor Driver
; xxxInit.n Script I/O processor assembly code for xxxLib Driver
;
; Copyright 1989-1996 Wind River Systems, Inc.
;
;/*
;Modification history
;--------------------
;01a,28jun95,jds Created. Adapted from ncr710init.n
;
;
;INTERNAL
;This file contains the assembly level SCSI scripts instructions which are
;used in conjunction with a higher level controller driver. To operate in
;SCSI SCRIPTS mode the SCSI I/O Processor requires only a SCRIPTS start
;address and a signal to begin operation. At that point, the processor
;begins fetching instructions from external memory and then executes them.
;The start address is written to the DMA SCRIPTS Pointer (DSP) register,
;which acts like a typical program counter. All SCRIPT instructions are
;fetched from external memory. The SCSI I/O Processor fetches and executes
;its own instructions by becoming a bus master on the host bus. Instructions
;are executed until a SCSI SCRIPTS interrupt instruction is encountered or
;until an unexpected interrupt causes an interrupt to the external
;processor. Once an interrupt is generated, the SCSI I/O Processor halts all
;operations until the interrupt is serviced. The further execution of
;SCRIPTS is then controlled by the SCSI controller driver which decides
;at which entry point should the SCRIPT processor start executing.
;
;There are four SCRIPT entry points which could be used by the controller
;driver. Execution thereafter is a function of the logic flow within the
;SCRIPTS and cannot be controlled by the driver. Thus, controll is
;transferred to the SCRIPTS processor by the controller driver at well known
;entry points and this control is returned to the controller driver by the
;SCRIPTS by generating a SCRIPTS interrupt. The four SCRIPTS entry points
;are described below:
;
;1) xxxWait
; If the SCSI controller is not connected to the bus, this entry point is
; used. The SCRIPTS processor waits for selection or re-selection by a SCSI
; target device (which acts as an initiator during selection), or can be
; interrupted by a new command from the host. This is done by signalling
; the processor via register bits. Thus this entry point puts the SCRIPTS
; processor into a passive mode.
I
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