Datasheet

Section 22 ROM
R01UH0166EJ0600 Rev. 6.00 Page 967 of 1434
Mar 02, 2011
H8S/2633 Group, H8S/2633 F-ZTAT
TM
,
H8S/2633R F-ZTAT
TM
, H8S/2695
To select user program mode, select a mode that enables the on-chip flash memory (mode 6 or 7),
and apply a high level to the FWE pin. In this mode, on-chip supporting modules other than flash
memory operate as they normally would in modes 6 and 7.
The flash memory itself cannot be read while the SWE1 bit is set to 1 to perform programming or
erasing, so the control program that performs programming and erasing should be run 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.
Figure 22.11 shows the procedure for executing the program/erase control program when
transferred to on-chip RAM.
Clear FWE*
FWE = high*
Branch to flash memory application
program
Branch to program/erase control
program in RAM area
Execute program/erase control
program (flash memory rewriting)
Transfer program/erase control
program to RAM
MD2, MD1, MD0 = 110, 111
Reset-start
Write the FWE assessment program and
transfer program (and the program/erase
control program if necessary) beforehand
Notes: Do not apply a constant high level to the FWE pin. Apply a high level to the FWE pin
only when the flash memory is programmed or erased. Also, while a high level is
applied to the FWE pin, the watchdog timer should be activated to prevent
overprogramming or overerasing due to program runaway, etc.
* For further information on FWE application and disconnection, see section 22.13,
Flash Memory Programming and Erasing Precautions.
Figure 22.11 User Program Mode Execution Procedure