SCSI Registers
4-89
asynchronous mode. It is also used to write to the
synchronous data FIFO when testing the chip. The
power-up value of this register is indeterminate.
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 actually 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 will be
automatically cleared after being accounted for. In the
case of a SCSI receive, all data will be 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
LSI53C1000 will use
when the WSR bit is cleared and
Mismatch Jump Address Two (PMJAD2)
when the WSR
bit is set. When this bit is set, the LSI53C1000 will use
Phase Mismatch Jump Address One (PMJAD1)
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
7
6
5
4
3
2
1
0
ENPMJ
PMJCTL
ENNDJ
DISFC
R
DISRC
R
0
0
0
0
x
x
0
x
Содержание LSI53C1000
Страница 6: ...vi Preface...
Страница 16: ...xvi Contents...
Страница 28: ...1 12 Introduction...
Страница 234: ...4 124 Registers...
Страница 314: ...6 40 Specifications This page intentionally left blank...
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Страница 344: ...6 70 Specifications This page intentionally left blank...
Страница 350: ...6 76 Specifications Figure 6 42 LSI53C1000 329 Ball Grid Array Bottom view...
Страница 352: ...6 78 Specifications...
Страница 360: ...A 8 Register Summary...
Страница 376: ...IX 12 Index...