Renesas SH7041 Series, Hardware Manual, Page: 717 / 923

679
Address
Data
V
PP
V
CC
CE
PGM
OE
Write Verify
t
AH
Read data
t
DF
t
DH
t
DS
t
AS
t
VPS
Write data
t
VCS
t
CES
t
PW
(t
OPW
)
*
t
OES
t
OE
V
PP
V
CC
V
CC
+ 1
V
CC
Note:
*
t
OPW
is defined by the values noted in the flowchart (figure 19.6).
Figure 21.7 Write/Verify Timing
21.3.3 Cautions on Writing
1. Writes must always be done with the established voltage and timing. The write voltage
(programming voltage) V
PP
is 12.5 V (when the EPROM writer is set for the HN27C101
Hitachi specifications, V
PP
becomes 12.5 V). Devices will sometimes be destroyed if a voltage
higher than the rated one is applied. Pay particular attention to such phenomena as EPROM
writer overshoot.
2. Always confirm that the indices of the EPROM writer socket, socket adapter, and device are in
agreement before programming. Devices will sometimes be destroyed due to excessive current
flow if these are not connected in the proper locations.
3. Do not touch the socket adapter or device during writing. Contact faults can sometimes cause
devices to be improperly written.
4. Page programming mode writes are not possible. Always set to byte programming mode.