HD64F2149 Datasheet, PDF (707/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

22.6.1 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 chip’s pins have been set to boot mode, the boot program
built into the chip is started and the programming control program prepared in the host is serially
transmitted to the chip via the SCI. In the chip, 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 22.7, and the boot program mode
execution procedure in figure 22.8.
The chip
Host
Flash memory
Write data reception
Verify data transmission
RxD1
SCI1
TxD1
On-chip RAM
Figure 22.7 System Configuration in Boot Mode
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