m37516e6hp Renesas Electronics Corporation., m37516e6hp Datasheet - Page 55

• Manufacturer Part Number: m37516e6hp
• Description: Single-chip 8-bit Cmos Microcomputer
• Manufacturer: Renesas Electronics Corporation.

7516 Group
Precautions on CPU Rewrite Mode
Described below are the precautions to be observed when rewriting
the flash memory in CPU rewrite mode.
(1) Operation speed
(2) Instructions inhibited against use
(3) Interrupts inhibited against use
(4) Watchdog timer
(5) Reset
Rev.1.01
During CPU rewrite mode, set the internal clock frequency 4.0
MHz or less using the main clock division ratio selection bits (bit
6, 7 at 003B
The instructions which refer to the internal data of the flash
memory cannot be used during CPU rewrite mode .
The interrupts cannot be used during CPU rewrite mode be-
cause they refer to the internal data of the flash memory.
In case of the watchdog timer has been running already, the in-
ternal reset generated by watchdog timer underflow does not
happen, because of watchdog timer is always clearing during
program or erase operation.
Reset is always valid. In case of CNV
leased, boot mode is active. So the program starts from the ad-
dress contained in address FFFC
area.
Jul 01, 2003
16
).
page 53 of 89
16
and FFFD
SS
= H when reset is re-
16
in boot ROM