HD64F2145 Datasheet, PDF (619/829 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

23.2 Mode Transitions
When the mode pins are set in the reset state and a reset-start is executed, this LSI enters an
operating mode as shown in figure 23.2. 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.
The differences between boot mode and user program mode are shown in table 23.1. Figure 23.3
shows the boot mode and figure 23.4 shows the user program mode.
User mode
(on-chip ROM
enabled)
MD1 ^{= 1}
=⁰
FLSHE = 1
SWE = 1
FLSHE = 0
SWE = 0
User
program
mode
Reset state
*²
*¹
Boot mode
On-board programming mode
=0
Programmer
mode
Notes: Only make a transition between user mode
and user program mode when the CPU is not
accessing the flash memory.
1. MD1 = MD0 = 0, P92 = P91 = P90 = 1
2. MD1 = MD0 = 0, P92 = 0, P91 = P90 = 1
Figure 23.2 Flash Memory State Transitions
Table 23.1 Differences between Boot Mode and User Program Mode
Boot Mode
User Program Mode
Total erase
Yes
Yes
Block erase
No
Yes
Programming control program* Program/program-verify
Program/program-verify
Erase/erase-verify
Note:* Should be provided by the user, in accordance with the recommended algorithm.
Rev. 2.0, 08/02, page 579 of 788