Datasheet

Table Of Contents
Section 19 Flash Memory (F-ZTAT Version)
Page 660 of 846 REJ09B0140-0900 Rev. 9.00
Sep 16, 2010
H8S/2215 Group
Use the recommended algorithm when programming and erasing flash memory.
The recommended algorithm enables programming and erasing to be carried out without
subjecting the device to voltage stress or sacrificing program data reliability. When setting the
P1 or E1 bit in FLMCR1, the watchdog timer should be set beforehand as a precaution against
program runaway, etc.
Do not set or clear the SWE1 bit during execution of a program in flash memory.
Wait for at least θ µs
*
after clearing the SWE1 bit before executing a program or reading data
in flash memory. When the SWE1 bit is set, data in flash memory can be rewritten, but access
flash memory only for verify operations (verification during programming/erasing). Also, do
not clear the SWE1 bit during programming, erasing, or verifying. Similarly, when using
emulation by RAM with a high level applied to the FWE pin, the SWE1 bit should be cleared
before executing a program or reading data in flash memory. However, read/write accesses can
be performed in the RAM area overlapping the flash memory space regardless of whether the
SWE1 bit is set or cleared.
Do not use interrupts while flash memory is being programmed or erased.
All interrupt requests, including NMI, should be disabled during FWE application to give
priority to program/erase operations.
Do not perform additional programming. Erase the memory before reprogramming.
In on-board programming, perform only one programming operation on a 128-byte
programming unit block. In programmer mode, too, perform only one programming operation
on a 128-byte programming unit block. Programming should be carried out with the entire
programming unit block erased.
Before programming, check that the chip is correctly mounted in the PROM programmer.
Overcurrent damage to the device can result if the index marks on the PROM programmer
socket, socket adapter, and chip are not correctly aligned.
Do not touch the socket adapter or chip during programming.
Touching either of these can cause contact faults and write errors.
The reset state must be entered after powering on
Apply the reset signal for at least 100 µs during the oscillation setting period.
When a reset is applied during operation, this should be done while the SWE1 pin is low.
Wait at least θ µs
*
after clearing the SWE1 bit before applying the reset.
Note: * Refer to section 24.8, Flash Memory Characteristics.