Fujitsu MB91260B Series Hardware Manual page 492

■ Notes on Using Debugger
●
Stepping of the RETI instruction
In the environment where interruptions occur frequently during stepping, the RETI is executed repeatedly
for the corresponding interrupt processing routines after the stepping. As the result of it, the main routine
and low-interrupt-level programs are not executed.
To avoid this situation, do not step the RETI instruction. Otherwise, perform debugging by disabling the
interruptions when the debug on the corresponding interrupt routines becomes unnecessary.
●
Operand break
Do not set the access to the areas containing the address of system stack pointer as a target of data event
break.
●
Debugging on unused area of FLASH memory
If debug is performed on the unused area of FLASH memory (where data is 0XFFFF
will not be accepted. To avoid this situation, the use of address mask function of debugger code event is
recommended to break when an instruction is accessing to the unused area.
●
Power-on debug
When powering off by the power-on debug, be sure to power off under the condition that all the following
three requirements are met.
(1) Time taken to decrease user power supply from 0.9 V
Note: If using two power supplies, V
(2) CPU operating frequency is 1 MHz or higher.
(3) User program is in execution.
●
Interrupt handler for NMI request (tool)
When ICE is unconnected, to prevent the malfunction caused by noise or other sources affecting DSU pin
to set a flag which is only set by the break request from ICE, add the following programs to the interrupt
handler.
ICE can be used even if this program is added.
Location to add
The following interrupt handler
Interrupt factor
Interrupt No.
Offset
TBR as a default address
Additional program
STM
LDI
LDI
STB
LDM
RETI
CC
: NMI request (tool)
: 13 (decimal), 0D (hexadecimal)
: 3C8
: 000FFFC8
(R0, R1)
#B00H, R0 ; B00 is the address of break factor register of DSU.
H
#0, R1
R1, @R0 ; Clear break factor register.
(R0, R1)
APPENDIX F Precautions on Handling
to 0.5 V
CC CC
is external I/O power supply voltage.
H
H
) by mistake, break
H
is 25 µs or more.
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