Avago Technologies LSI53C1000R - Manual (Page 169)

SCSI Registers 4-57
Version 2.2 Copyright © 2000–2003 by LSI Logic Corporation. All rights reserved.
registers. Each of the eight bytes that make up the 64-bit
DMA FIFO is accessed by writing these bits to the proper
value. For normal operation, FBL3 must equal zero.
Register: 0x22
Chip Test Five (CTEST5)
Read/Write
ADCK Clock Address Incrementor 7
Setting this bit increments the address pointer contained
in the
DMA Next Address (DNAD) register. The DNAD
register is incremented based on the DNAD contents and
the current
DMA Byte Counter (DBC) value. This bit
automatically clears itself after incrementing the DNAD
register.
BBCK Clock Byte Counter 6
Setting this bit decrements the byte count contained in
the 24-bit
DMA Byte Counter (DBC) register. It is
decremented based on the DBC contents and the current
DMA Next Address (DNAD) value. This bit automatically
clears itself after decrementing the DBC register.
FBL3 FBL2 FBL1 FBL0
DMA FIFO
Byte Lane Pins
0 x x x Disabled N/A
1 0 0 0 0 D[7:0]
1 0 0 1 1 D[15:8]
1 0 1 0 2 D[23:16]
1 0 1 1 3 D[31:24]
1 1 0 0 4 D[39:32]
1 1 0 1 5 D[47:40]
1 1 1 0 6 D[53:48]
1 1 1 1 7 D[63:54]
7 6 5 3 2 1 0
ADCK BBCK R BL2 R
0 0 0 0 0 0 0 0