NEC ?PD703302, Руководство пользователя

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CHAPTER 24 ROM CORRECTION FUNCTION
User’s Manual U16896EJ2V0UD
623
Figure 24-2. ROM Correction Operation and Program Flow
Reset & start
Fetch address
= CORADn?
CORADn = DBPC
−
2?
CORENn bit = 1?
Initialize microcontroller
Set CORADn register
Change fetch code to
DBTRAP instruction
Branch to ROM correction
judgment address
Branch to correction code address
of corresponding channel n
Execute fetch code
Read data for setting ROM
correction from external memory
Execute DBTRAP instruction
Jump to address 00000060H
Execute correction code
Execute DBRET instruction
Write return address to
DBPC.
Write value of PSW to
DBPSW as necessary.
Set CORCN register
Yes
Yes
Yes
No
No
Remarks 1. : Processing by user program (software)
2. n = 0 to 3
: Processing by ROM correction (hardware)
Load program for judgment
of ROM correction and
correction codes
Execute fetch code
ILGOP processing
No