HD6432142 datasheet(746/1177 Pages) RENESAS

746 / 1177 page

Section 23 ROM (H8S/2148 F-ZTAT A-Mask Version, H8S/2147 F-ZTAT A-Mask Version, H8S/2144 F-ZTAT A-Mask Version)

Rev. 4.00 Sep 27, 2006 page 702 of 1130

REJ09B0327-0400

23.6.1

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 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 23.7, and the boot program mode

execution procedure in figure 23.8.

RxD1

TxD1

SCI1

The chip

Flash memory

Write data reception

Verify data transmission

Host

On-chip RAM

Figure 23.7 System Configuration in Boot Mode

HD6432142 Datasheet(PDF) 746 Page - Renesas Technology Corp