HD6432345 Datasheet, PDF (581/907 Pages) Hitachi Semiconductor – H8S/2345 F-ZTAT Hardware Manual

17.8.1 Boot Mode
When boot mode is used, the flash memory programming control program must be prepared in the
host beforehand. The channel 1 SCI to be used is set to asynchronous mode.
When a reset-start is executed after the H8S/2345 MCU’s pins have been set to boot mode, the
boot program built into the MCU is started and the programming control program prepared in the
host is serially transmitted to the MCU via the SCI. In the MCU, the programming control
program received via the SCI is written into the programming control program area in on-chip
RAM. After the transfer is completed, control branches to the start address of the programming
control program area and the programming control program execution state is entered (flash
memory programming is performed).
The transferred programming control program must therefore include coding that follows the
programming algorithm given later.
The system configuration in boot mode is shown in figure 17.15, and the boot program mode
execution procedure in figure 17.16.
H8S/2345 chip
Host
Flash memory
Write data reception
Verify data transmission
RxD1
SCI1
TxD1
On-chip RAM
Figure 17.15 System Configuration in Boot Mode
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