HD6432646 Hitachi, HD6432646 Datasheet - Page 707

• Manufacturer Part Number: HD6432646
• Description: (HD64F264x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

Bit 7: PDWND
0
1
Bits 6 to 0—Reserved: These bits always read 0.
20.6
When pins are set to on-board programming mode and a reset-start is executed, a transition is
made to the on-board programming state in which program/erase/verify operations can be
performed on the on-chip flash memory. There are two on-board programming modes: boot mode
and user program mode. The pin settings for transition to each of these modes are shown in table
20-5. For a diagram of the transitions to the various flash memory modes, see figure 20-2.
Table 20-5 Setting On-Board Programming Modes
Mode
Boot mode
User program mode
20.6.1
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 LSI’s pins have been set to boot mode, the boot program
built into the LSI is started and the programming control program prepared in the host is serially
transmitted to the LSI via the SCI. In the LSI, 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 20-6, and the boot mode execution
procedure in figure 20-7.
On-Board Programming Modes
Boot Mode
Description
Transition to flash memory power-down mode enabled
Transition to flash memory power-down mode disabled
Expanded mode
Single-chip mode
Expanded mode
Single-chip mode
FWE
1
1
MD2
0
0
1
1
MD1
1
1
1
1
(Initial value)
MD0
0
1
0
1
673