Flash Memory Operating Modes - Renesas H8S Series Hardware Manual

19.6.3

Flash Memory Operating Modes

Mode Transitions: When the mode pins and the FWE pin are set in the reset state and a reset-start is executed, the MCU
enters one of the operating modes shown in figure 19-8. In user mode, flash memory can be read but not programmed or
erased.
Flash memory can be programmed and erased in boot mode, user program mode, and programmer mode.
User mode with
on-chip ROM
enabled
FWE = 1
Notes: Only make a transition between user mode and user program mode when the CPU is
not accessing the flash memory.
1. MD
2. NMI = 1, FWE = 1, MD
Rev.6.00 Oct.28.2004 page 576 of 1016
REJ09B0138-0600H
MD = MD = 1
2 1
RES = 0
RES = 0
FWE = 0
User
program mode
On-board programming mode
= MD = MD = 0, P66 = 1, P65 = P64 = 0
2 1 0
= 0, MD
2
Figure 19-8 Flash Memory Mode Transitions
Reset state
*
1
*
2
RES = 0
Boot mode
= 1
1
RES = 0
Programmer
mode