UPD78F0138 NEC, UPD78F0138 Datasheet - Page 426

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

26.1 Functions of ROM Correction
program in the internal expansion RAM.
using the ROM correction.
26.2 Configuration of ROM Correction
426
The
Program bugs found in the mask ROM or flash memory can be avoided, and program flow can be changed by
The ROM correction can correct two places (max.) of the internal ROM or internal flash memory (program).
Caution The ROM correction cannot be emulated by the in-circuit emulator.
The ROM correction includes the following hardware.
Figure 26-1 shows a block diagram of the ROM correction.
Remark n = 0, 1
µ
PD780136, 780138, and 78F0138 can replace part of a program in the mask ROM or flash memory with a
Program counter (PC)
register n (CORADn)
Correction address
Comparator
Registers
Control register
Item
Figure 26-1. Block Diagram of ROM Correction
Table 26-1. Configuration of ROM Correction
Match
Internal bus
CHAPTER 26 ROM CORRECTION
Correction address registers 0 and 1 (CORAD0, CORAD1)
Correction control register (CORCN)
CORENn CORSTn
User’s Manual U16228EJ2V0UD
Correction control register
Configuration
Branch instruction
generator
Correction branch request
signal (BR !F7FDH)