CHAPTER 3 HOW TO USE MINICUBE2 WITH V850 MICROCONTROLLER
User’s Manual U18371EJ1V0UM
33
(a) Reset vector
A reset vector includes the jump instruction for the debug monitor program.
[How to secure areas]
It is not necessary to secure this area intentionally. When downloading a program, however, the debugger
rewrites the reset vector in accordance with the following cases. If the rewritten pattern does not match the
following cases, the debugger generates an error (F0c34 when using the ID850QB).
• When two nop instructions are placed in succession from address 0
Before writing
After writing
0x0
nop
→
Jumps to debug monitor program at 0x0
0x2 nop
0x4 xxxx
0x4
xxxx
• When two 0xFFFF are successively placed from address 0 (already erased device)
Before writing
After writing
0x0
0xFFFF
→
Jumps to debug monitor program at 0x0
0x2 0xFFFF
0x4 xxxx
0x4
xxxx
• The
jr
instruction is placed at address 0 (when using NEC Electronics compiler CA850)
Before writing
After writing
0x0 jr disp22
→
Jumps to debug monitor program at 0x0
0x4 jr disp22 - 4
•
mov32
and
jmp
are placed in succession from address 0 (when using IAR compiler ICCV850)
Before writing
After writing
0x0 mov imm32,reg1
→
Jumps to debug monitor program at 0x0
0x6 jmp [reg1]
0x4 mov imm32,reg1
0xa jmp [reg1]
• The jump instruction for the debug monitor program is placed at address 0
Before writing
After writing
Jumps to debug monitor program at 0x0
→
No
change