Renesas H8S/2318 series, Руководство по оборудованию

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Rev. 5.00, 12/03, page 658 of 1088
17.20.6 Auto-Erase Mode
•
Auto-erase mode supports only total memory erasing.
•
Do not perform a command write during auto-erasing.
•
Confirm normal end of auto-erasing by checking I/O
6
. Alternatively, status read mode can also
be used for this purpose (the I/O
7
status polling pin is used to identify the end of an auto-erase
operation).
•
Status polling I/O
6
and I/O
7
pin information is retained until the next command write. As long
as the next command write has not been performed, reading is possible by enabling
CE
and
OE
.
AC Characteristics
Table 17-41 AC Characteristics in Auto-Erase Mode
(Conditions: V
CC
= 3.3 V ±0.3 V, V
SS
= 0 V, T
a
= 25°C ±5°C)
Item Symbol Min Max Unit
Command write cycle t
nxtc
20 —
µ
s
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
Status polling start time t
ests
1 — ms
Status polling access time t
spa
— 150 ns
Memory erase time t
erase
100 40000 ms
WE
rise time t
r
— 30 ns
WE
fall time t
f
— 30 ns