HD64F2638F20J Datasheet, PDF (821/1512 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2600 Series

H8S/2639, H8S/2638, H8S/2636,
H8S/2630, H8S/2635 Group
Section 21A ROM
(H8S/2636 Group)
21A.9 Flash Memory Programming/Erasing
A software method, using the CPU, is employed to program and erase flash memory in the on-
board programming modes. There are four flash memory operating modes: program mode, erase
mode, program-verify mode, and erase-verify mode. Transitions to these modes for on-chip flash
memory are made by setting the PSU, ESU, P, E, PV, and EV bits in FLMCR1.
The flash memory cannot be read while being programmed or erased. Therefore, the program
(user program) that controls flash memory programming/erasing should be located and executed in
on-chip RAM or external memory. If the program is to be located in external memory, the
instruction for writing to flash memory, and the following instruction, should be placed in on-chip
RAM. Also ensure that the DTC is not activated before or after execution of the flash memory
write instruction.
In the following operation descriptions, wait times after setting or clearing individual bits in
FLMCR1 are given as parameters; for details of the wait times, see section 24.1.7, Flash Memory
Characteristics.
Notes: 1. Operation is not guaranteed if setting/resetting of the SWE, ESU, PSU, EV, PV, E, and
P bits in FLMCR1 is executed by a program in flash memory.
2. When programming or erasing, set FWE to 1 (programming/erasing will not be
executed if FWE = 0).
3. Programming must be executed in the erased state. Do not perform additional
programming on addresses that have already been programmed.
REJ09B0103-0800 Rev. 8.00
May 28, 2010
Page 771 of 1458