UPD78F0138 NEC, UPD78F0138 Datasheet - Page 430

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

26.5 ROM Correction Application
430
How to apply the example shown in 26.4 is described below.
(1) Store the correction address and instruction after correction (patch program) to nonvolatile memory (such as
EEPROM
When two places should be corrected, store the branch destination judgment program as well. The branch
destination judgment program checks which one of the addresses set to correction address registers 0 and 1
(CORAD0 or CORAD1) generates the correction branch.
TM
Figure 26-5. Example of Storing to EEPROM (When One Place Is Corrected)
) outside the microcontroller.
FFH
00H
01H
02H
00
10
0D
02
9B
02
10
EEPROM
CHAPTER 26 ROM CORRECTION
User’s Manual U16228EJ2V0UD
RA78K/0
CSEG
DW
ADD
BR
Source Program
AT
0000H
#1000H
A, #2
!1002H