Chip control zero (ccntl0), Register: 0x56 – Avago Technologies LSI53C1010R User Manual
Page 211

SCSI Registers
4-93
Version 2.2
Copyright © 2000–2003 by LSI Logic Corporation. All rights reserved.
Register: 0x56
Chip Control Zero (CCNTL0)
Read/Write
ENPMJ
Enable Phase Mismatch Jump
7
Upon setting this bit, any phase mismatches do not
interrupt but force a jump to an alternate location to
handle the phase mismatch. Prior to taking the jump, the
appropriate remaining byte counts and addresses are
calculated to facilitate storage.
In the case of a SCSI send, any data in the part is
automatically cleared after being accounted for. In the
case of a SCSI receive, all data is flushed out of the part
and accounted for prior to taking the jump. This feature
does not cover, however, the byte that may appear in
. This byte must be
flushed manually.
This bit also enables the flushing mechanism to flush
data during a Data-In phase mismatch in a more
efficient manner.
PMJCTL
Jump Control
6
This bit controls which decision mechanism is used when
jumping on phase mismatch. When this bit is cleared, the
LSI53C1010R uses
Phase Mismatch Jump Address One (PMJAD1)
when the
WSR bit is cleared and
Phase Mismatch Jump Address Two (PMJAD2)
when the
WSR bit is set. When this bit is set, the LSI53C1010R
uses
Phase Mismatch Jump Address Two (PMJAD2)
on
Data-Out (Data-Out, Command, Message-Out) transfers
and
Phase Mismatch Jump Address Two (PMJAD2)
on
Data-In (Data-In, Status, Message-In) transfers. The
phase referred to here is the phase encoded in the block
move SCRIPTS instruction, not the phase on the SCSI
bus that caused the phase mismatch.
7
6
5
4
3
2
1
0
ENPMJ
PMJCTL
ENNDJ
DISFC
R
DISRC
DPR
0
0
0
0
x
x
0
0