HD6475348R Datasheet, PDF (98/487 Pages) Hitachi Semiconductor – Single-Chip Microcomputer

3.9 Programming Notes
3.9.1 Restriction on Address Location
The following restriction applies when instructions are located in on-chip RAM.
• Restriction
Instruction execution cannot proceed continuously from an external address to on-chip RAM.
• Solution
To execute instructions located in on-chip RAM, use a branch instruction (examples: Bcc, JMP,
etc.) to branch to the first instruction located in on-chip RAM. Do not place instruction code in
the last three bytes of external memory (H'F67D to H'F67F).
H'F67A
H'F67B
H'F67C
H'F67D
H'F67E
H'F67F
H'F680
H'F681
NOP
NOP
NOP
NOP
NOP
NOP
NOP
NOP
Not
executable
H'F67A
H'F67B
H'F67C
H'F67D
H'F67E
H'F67F
H'F680
H'F681
NOP
BRA
disp
NOP
NOP
Do not
place
instruction
code here
Branch
Execution Disabled
Execution Enabled
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