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AMD
P R E L I M I N A R Y
136
Am79C930
ISA ACCESS
Parameter
Symbol
t
i
1
t
i
2
t
i
3
t
i
4
t
i
7
t
i
8
t
i
9
t
i
10
t
i
11
t
i
12
t
i
13
t
i
14
t
i
15
t
i
16
t
i
20
t
i
21
Parameter Description
LA[23:17] valid setup to BALE
↓
BALE
↑
to BALE
↓
pulse width
LA[23:17] valid hold from BALE
↓
LA[23:17] valid setup to
CMD
↓
SA[16:0] valid setup to
CMD
↓
CMD
↓
to
CMD
↑
pulse width
SA[16:0] valid setup to BALE
↓
Data valid delay from
RCMD
↓
Data valid setup to
WCMD
↓
SA[16:0] valid hold from
CMD
↑
CMD
↑
to
CMD
↓
pulse width
Data valid hold from
RCMD
↑
Data valid hold from
WCMD
↑
Data disabled from
RCMD
↑
IOCHRDY
↓
delay from
CMD
↓
IOCHRDY
↓
to IOCHRDY
↑
pulse width
CMD
↑
delay from IOCHRDY
↑
BALE
↑
delay from
CMD
↑
Data valid delay from IOCHRDY
↑
LA[23:17] valid hold from
CMD
↓
AEN valid setup to
CMD
↓
AEN valid hold from
CMD
↑
AEN valid setup to BALE
↓
Data enabled from
RCMD
↓
Test Conditions
Min
60
25
12
80
25
Max
Unit
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
Note 1
Note 1
Note 4
6*T
CLKIN
20
Notes 2, 5, 6
Note 3
Note 1
Note 1
Note 2
Note 3
Note 2, 6
Notes 1, 7
Notes 5, 6, 7
53 X T
CLKIN
–75
20
55
0
20
20
60
0
130 +
53 X T
CLKIN
t
i
22
t
i
23
t
i
25
t
i
26
t
i
30
t
i
31
t
i
32
t
i
34
Notes 1, 7
Note 1
Note 7
Note 1
Note 1
Note 1
35
20
ns
ns
ns
ns
ns
ns
ns
ns
–T
CLKIN
–15
80
15
60
0
25
Notes 2, 4
110
Notes:
1.
CMD
= one of:
MEMR
,
MEMW
,
IOR
or
IOW
.
2.
RCMD
= one of:
MEMR
, or
IOR
.
3.
WCMD
= one of:
MEMW
, or
IOW
.
4. If no wait states are incurred.
5. The max value for this parameter assumes the following worst case situation:
Value
Worst Case
0
FLASH and SRAM wait states set at “3.”
1
Host performs ISA WRITE cycle at same time that Am79C930 embedded 80188 controller begins
instruction fetch cycle to FLASH memory.
2
ISA WRITE cycle is posted internal to Am79C930 device, pending the completion of the embedded 80188
controller access.
3
Host performs ISA READ cycle immediately following completion of ISA WRITE cycle.
4
After completion of first embedded 80188 access to FLASH, posted ISA WRITE executes to SRAM;
ISA READ stycle is being held in wait state.
5
After completion of posted ISA WRITE cycle, new embedded 80188 access to FLASH begins.
6
After completion of second embedded 80188 access to FLASH, ISA READ cycle is allowed to proceed
onto memory bus to SRAM; host is still held in wait state.
7
At SRAM READ cycle completion, data is delivered to ISA bus and wait state is exited.
6. Parameter is not included in production test.
7. Parameter only applies when IOCHRDY is deasserted.