Boot Mode - Renesas H8S/2633 Series Hardware Manual

22.6.1

Boot Mode

When boot mode is used, the flash memory programming control program must be prepared in the
host beforehand. The SCI channel to be used is set to asynchronous mode.
When a reset-start is executed after the H8S/2633 Series' pins have been set to boot mode, the
boot program built into the H8S/2633 Series is started and the programming control program
prepared in the host is serially transmitted to the H8S/2633 Series via the SCI. In the H8S/2633
Series, 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 mode execution
procedure in figure 22-8.
Host
Write data reception
Verify data transmission
Figure 22-7 System Configuration in Boot Mode
H8S/2633 Series
Flash memory
RxD2
SCI2
On-chip RAM
TxD2
917