20.11.3 Memory Read Mode - Hitachi H8S/2646 Hardware Manual

Table 20-11 Programmer Mode Commands
Command Name
Memory read mode
Auto-program mode
Auto-erase mode
Status read mode
Notes: 1. In auto-program mode, 129 cycles are required for command writing by a simultaneous
128-byte write.
2. In memory read mode, the number of cycles depends on the number of address write
cycles (n).

20.11.3 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.
2. In memory read mode, command writes can be performed in the same way as in the command
wait state.
3. Once memory read mode has been entered, consecutive reads can be performed.
4. After powering on, memory read mode is entered.
Table 20-12 AC Characteristics in Transition to Memory Read Mode
(Conditions: V
Item
Command write cycle
CE hold time
CE setup time
Data hold time
Data setup time
Write pulse width
WE rise time
WE fall time
Number
of Cycles Mode
1 + n Write
129 Write
2 Write
2 Write
= 5.0 V ±0.5 V, V
CC
Symbol
t
nxtc
t
ceh
t
ces
t
dh
t
ds
t
wep
t
r
t
f
1st Cycle
Address Data
X H'00
X H'40
X H'20
X H'71
= 0 V, T = 25°C ±5°C)
SS a
Min
20
0
0
50
50
70
—
—
2nd Cycle
Mode Address Data
Read RA
Write WA
Write X
Write X
Max Unit
— µs
— ns
— ns
— ns
— ns
— ns
30 ns
30 ns
Dout
Din
H'20
H'71
699