Datasheet

Section 22 ROM
R01UH0166EJ0600 Rev. 6.00 Page 945 of 1434
Mar 02, 2011
H8S/2633 Group, H8S/2633 F-ZTAT
TM
,
H8S/2633R F-ZTAT
TM
, H8S/2695
22.4.3 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
microcomputer enters an operating mode as shown in figure 22.3. In user mode, flash memory can
be read but not programmed or erased.
The boot, user program and programmer modes are provided as modes to write and erase the flash
memory.
Boot mode
On-board programming mode
User
program mode
User mode
(on-chip ROM
enabled)
Reset state
Programmer
mode
RES = 0
FWE = 1 FWE = 0
*
1
*
1
*
2
Notes: Only make a transition between user mode and user program mode when the CPU is
not accessing the flash memory.
1. RAM emulation possible
2. This LSI transits to programmer mode by using the dedicated PROM programmer.
RES = 0
MD1 = 0,
MD2 = 0,
FWE = 1
RES = 0
RES = 0
MD1 = 1,
MD2 = 1,
FWE = 0
MD1 = 1,
MD2 = 1,
FWE = 1
Figure 22.3 Flash Memory State Transitions