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Section 6 ROM
Rev. 6.00 Sep 12, 2006 page 161 of 526
REJ09B0326-0600
•
Oscillation must have stabilized (following the elapse of the oscillation settling time) or
be stopped.
When the V
CC
power is turned on, hold the
RES
pin low for the duration of the
oscillation settling time*
2
(t
rc
= 20 ms) before applying V
PP
.
•
The MCU must be in the reset state, or in a state in which reset has ended normally
(reset has been released) and flash memory is not being accessed.
Apply or release V
PP
either in the reset state, or when the CPU is not accessing flash
memory (when a program in on-chip RAM or external memory is executing). Flash
memory data cannot be read normally at the instant when V
PP
is applied or released, so
do not read flash memory while V
PP
is being applied or released.
For a reset during operation, apply or release V
PP
only after the
RES
pin has been held
low for at least 10 system clock cycles (10
φ
).
•
The P and E bits must be cleared in the flash memory control register (FLMCR).
When applying or releasing V
PP
, make sure that the P or E bit is not set by mistake.
•
There must be no program runaway.
When V
PP
is applied, program execution must be supervised, e.g. by the watchdog
timer.
These power-on and power-off timing requirements for V
CC
and V
PP
should also be
satisfied in the event of a power failure and in recovery from a power failure. If these
requirements are not satisfied, overprogramming or overerasing may occur due to program
runaway, etc., which could cause memory cells to malfunction.
b. The V
PP
flag is set and cleared by a threshold decision on the voltage applied to the FV
PP
pin. The threshold level is approximately in the range from V
CC
+2 V to 11.4 V.
When this flag is set, it becomes possible to write to the flash memory control register
(FLMCR) and the erase block registers (EBR1 and EBR2), even though the V
PP
voltage
may not yet have reached the programming voltage range of 12.0 V ±0.6 V.
Do not actually program or erase the flash memory until V
PP
has reached the programming
voltage range.
The programming voltage range for programming and erasing flash memory is 12.0 V ±0.6
V (11.4 V to 12.6 V). Programming and erasing cannot be performed correctly outside this
range. When not programming or erasing the flash memory, insure that the V
PP
voltage
does not exceed the V
CC
voltage. This will prevent unintentional programming and erasing.
Notes: 1. Definitions of V
PP
application, release, and cut-off are as follows:
Application: Raising the voltage from V
CC
to 12.0 V ±0.6 V
Release:
Dropping the voltage from 12.0 V ±0.6 V to V
CC
Cut-off:
Halting voltage application (floating state)
2. The time depends on the resonator used; refer to the electrical characteristics.
Содержание F-ZTAT H8/3642A Series
Страница 6: ...Rev 6 00 Sep 12 2006 page iv of xx ...
Страница 8: ...Rev 6 00 Sep 12 2006 page vi of xx ...
Страница 21: ...Rev 6 00 Sep 12 2006 page xix of xx Appendix E Product Code Lineup 522 Appendix F Package Dimensions 524 ...
Страница 22: ...Rev 6 00 Sep 12 2006 page xx of xx ...
Страница 124: ...Section 5 Power Down Modes Rev 6 00 Sep 12 2006 page 102 of 526 REJ09B0326 0600 ...
Страница 188: ...Section 6 ROM Rev 6 00 Sep 12 2006 page 166 of 526 REJ09B0326 0600 ...
Страница 190: ...Section 7 RAM Rev 6 00 Sep 12 2006 page 168 of 526 REJ09B0326 0600 ...
Страница 298: ...Section 9 Timers Rev 6 00 Sep 12 2006 page 276 of 526 REJ09B0326 0600 ...
Страница 378: ...Section 12 A D Converter Rev 6 00 Sep 12 2006 page 356 of 526 REJ09B0326 0600 ...
Страница 446: ...Section 13 Electrical Characteristics Rev 6 00 Sep 12 2006 page 424 of 526 REJ09B0326 0600 ...