Boot Mode - Renesas Hitachi H8S/2194 Series Hardware Manual

8.4.1

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 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 SCI1. In the MCU, the programming control program
received via the SCI1 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 8.7, and the boot program mode
execution procedure in figure 8.8.
Host
Write data reception
Verify data
transmission
Figure 8.7 System Configuration in Boot Mode
This LSI
Flash memory
SI1
SCI1
On-chip RAM
SO1
Rev. 2.0, 11/00, page 189 of 1037