Hitachi H8/3692 ユーザーズマニュアル

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Rev. 1.0, 07/01, page 98 of 372
7.6.3
Memory Read Mode
1. After completion of auto-program/auto-erase/status read operations, a transition is made to the
command wait state. When reading memory contents, a transition to memory read mode must
first be made with a command write, after which the memory contents are read. Once memory
read mode has been entered, consecutive reads can be performed.
2. In memory read mode, command writes can be performed in the same way as in the command
wait state.
3. After powering on, memory read mode is entered.
4.
 
Tables 7-8 to 7-10 show the AC characteristics.
Table 7-8
AC Characteristics in Transition to Memory Read Mode (First Cycle)
(Conditions: V
CC
 = 5.0 V ±0.5 V, V
SS
 = 0 V, T
a
 = 25°C ±5°C)
Item
Symbol
Min
Max
Unit
Notes
Command write cycle
t
nxtc
20
µs
Figure 7-6
CE
 hold time
t
ceh
0
ns
CE
 setup time
t
ces
0
ns
Data hold time
t
dh
50
ns
Data setup time
t
ds
50
ns
Write pulse width
t
wep
70
ns
WE
 rise time
t
r
30
ns
WE
 fall time
t
f
30
ns
A15–A0
I/O7–I/O0
Note:  Data is latched on the rising edge of 
.
t
ceh
t
wep
t
f
t
r
t
ces
t
nxtc
Address stable
t
ds
t
dh
Command write
Memory read mode
Figure 7-6   Timing Waveforms for Memory Read after Memory Write