Filter
Top Products
I/O Instruction 5-13
5.3.2 Second Dword
Start Address [31:0]
This 32-bit field specifies the starting address of the data
to move to/from memory. This field is copied to the DMA
Next Address (DNAD) register. When the LSI53C875A
transfers data to or from memory, the DNAD register is
incremented by the number of bytes transferred.
When bit 29 is set, indicating indirect addressing, this
address is a pointer to an address in memory that points
to the data location. When bit 28 is set, indicating table
indirect addressing, the value in this field is an offset into
atablepointedtobytheData Structure Address (DSA).
The table entry contains byte count and address
information.
5.4 I/O Instruction
I/O Instructions perform the following SCSI operations in Target and
Initiator mode. These I/O operations are chosen with the opcode bits in
the DMA Command (DCMD) register.
This section describes these I/O operations.
31 0
DMA SCRIPTS Pointer Save (DSPS) Register
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
OPC2 OPC1 OPC0 Target Mode Initiator Mode
0 0 0 Reselect Select
0 0 1 Disconnect Wait Disconnect
0 1 0 Wait Select Wait Reselect
011Set Set
1 0 0 Clear Clear