Dma scripts pointer (dsp), Scripts pointer (dsp), Dma command (dcmd) – Avago Technologies LSI53C895A User Manual
Page 173: Dma scripts, Pointer (dsp), Next address (dnad), Dma next address (dnad), Register: 0x27, Registers: 0x2c–0x2f
SCSI Registers
4-65
Register: 0x27
DMA Command (DCMD)
Read/Write
DCMD
DMA Command
[7:0]
This 8-bit register determines the instruction for the
LSI53C895A to execute. This register has a different
format for each instruction. For a complete description
see
Chapter 5, “SCSI SCRIPTS Instruction Set.”
Registers: 0x28–0x2B
DMA Next Address (DNAD)
Read/Write
DNAD
DMA Next Address
[31:0]
This 32-bit register contains the general purpose address
pointer. At the start of some SCRIPTS operations, its
value is copied from the
register. Its value may not be valid except in
certain abort conditions. The default value of this register
is zero.
Registers: 0x2C–0x2F
DMA SCRIPTS Pointer (DSP)
Read/Write
DSP
DMA SCRIPTS Pointer
[31:0]
To execute SCSI SCRIPTS, the address of the first
SCRIPTS instruction must be written to this register. In
normal SCRIPTS operation, once the starting address of
7
0
DCMD
0
1
x
x
x
x
x
x
31
0
DNAD
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
31
0
DSP
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0