SCSI Registers
4-79
SEL[3:0]
Selection Time-Out
[3:0]
These bits select the SCSI selection/reselection time-out
period. When this timing (plus the 200
µ
s selection abort
time) is exceeded, the STO bit in the
register is set. For a more detailed
explanation of interrupts, refer to
Register: 0x49
SCSI Timer One (STIME1)
Read/Write
R
Reserved
7
HTHBA
Handshake-to-Handshake Timer Bus Activity
Enable
6
Setting this bit causes this timer to begin testing for SCSI
REQ/ and ACK/ activity as soon as SBSY/ is asserted,
regardless of the agents participating in the transfer.
GENSF
General Purpose Timer Scale Factor
5
Setting this bit causes this timer to shift by a factor of 16.
Refer to the
register
description for details.
7
6
5
4
3
0
R
HTHBA
GENSF
HTHSF
GEN[3:0]
x
0
0
0
0
0
0
0
HTH[3:0], SEL[3:0], GEN[3:0]
Minimum Time-out
HTHSF = 0,
GENSF = 0
HTHSF = 1,
GENSF = 1
0000
Disabled
Disabled
0001
125
µ
s
2 ms
0010
250
µ
s
4 ms
0011
500
µ
s
8 ms
0100
1
µ
s
16 ms
0101
2 ms
32 ms
0110
4 ms
64 ms
0111
8 ms
128 ms
1000
16 ms
256 ms
1001
32 ms
512 ms
1010
64 ms
1 s
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 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...