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User’s Manual U16896EJ2V0UD
620
CHAPTER 24 ROM CORRECTION FUNCTION
24.1 Overview
The ROM correction function is used to replace part of the program in the internal ROM with the program of an
external memory or the internal RAM.
By using this function, program bugs found in the internal ROM can be corrected.
Up to four addresses can be specified for correction.
Figure 24-1. Block Diagram of ROM Correction
Instruction address bus
Block replacing
bug with DBTRAP
instruction
Instruction data bus
Internal ROM
DBTRAP instruction
generation block
Correction
address register n
(CORADn)
Correction control
register (CORENn bit)
Comparator
Remark
n = 0 to 3