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W78E858
6.3.3
Data Read Cycle
PARAMETER
SYMBOL
MIN.
TYP.
MAX.
UNIT
NOTES
ALE Low to RD Low
Tdar
3 TCP-
Δ
-
3 TCP+
Δ
nS
1, 2
RD
Low to Data Valid
Tdda
-
4 TCP
nS
1
Data Hold from RD High
Tddh
0
-
2 TCP
nS
Data Float from RD High
Tddz
0
-
2 TCP
nS
RD
Pulse Width
Tdrd
6 TCP-
Δ
6 TCP
-
nS
2
Notes:
1. Data memory access time is 8 TCP.
2. "
Δ" (due to buffer driving delay and wire loading) is 20 nS.
6.3.4
Data Write Cycle
PARAMETER
SYMBOL
MIN.
TYP.
MAX.
UNIT
ALE Low to WR Low
TDAW
3 TCP-
Δ
-
3 TCP+
Δ
nS
Data Valid to WR Low
TDAD
1 TCP-
Δ
-
nS
Data Hold from WR High
TDWD
1 TCP-
Δ
-
nS
WR
Pulse Width
TDWR
6 TCP-
Δ
6 TCP
-
nS
Note:
"
Δ" (due to buffer driving delay and wire loading) is 20 nS.
6.3.5
Port Access Cycle
PARAMETER
SYMBOL
MIN.
TYP.
MAX.
UNIT
Port Input Setup to ALE Low
TPDS
1 TCP
-
nS
Port Input Hold from ALE Low
TPDH
0
-
nS
Port Output to ALE
TPDA
1 TCP
-
nS
Note:
Ports are read during S5P2, and output data becomes available at the end of S6P2. The timing data are referenced to
ALE, since it provides a convenient reference.
6.3.6
Flash Mode Timing
PARAMETER
SYMBOL
MIN.
TYP.
MAX.
UNIT
NOTES
Reset Valid
TRV
9
10
11
μS
-
Enter Flash Mode Reset Low
TEFRL
9
10
11
μS
-
Program Pulse High
TPPH
18
20
22
μS
-
Program Pulse Low
TPPL
40
50
60
μS
-
Erase Pulse Low
TEPL
25
30
50
mS
-
Read Pulse Low
TRPL
1.35
1.5
1.65
μS
-
Address PreFix
TAPF
45
50
55
nS
-
Data Remain
TDR
81
90
99
nS
-
Publication Release Date: April 22, 2008
- 28 -
Revision A8