Avago Technologies LSI53C1010 - Manual (Page 189)

Device Driver Overview 8-3
Figure 8.2 SCSI Device Driver Layers
The hardware interface layer:
•
Interprets the operating system interface's formatted requests.
•
Prepares the SCSI device by initializing the DMA, SCSI, and
Interrupt registers and by loading the appropriate SCRIPTS into host
memory.
•
Reserves memory for any data buffers that will be used by the
SCRIPTS program.
•
Initializes data buffer addresses, byte counts, and SCSI IDs
embedded in the SCRIPTS code.
•
Starts the execution of the SCRIPTS routine by loading the DSP
register (0x2C–0x2F) with the address of the first SCRIPTS
instruction.
•
Waits for an interrupt to signal that the I/O is complete.
•
Passes I/O status information back to the operating system interface.
Operating System Interface Layer
Device Type Driver
Hardware Interface Layer
SCSI Hardware Specific Driver
SCSI SCRIPTS Sequences
Main Device Scheduler Reselected
I/O Scheduler
Vendor Specific Driver
(host adapter, mainboard)
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