Renesas M3028BT-EPB User Manual page 79

M3028BT-EPB User's Manual
Notes on Address-Match Interrupts:
When you use the address-match interrupt function in a user program, uncheck "Enable the Address Match
Interrupt Break Function" in the MCU tab of the Init dialog box of the emulator debugger. Thus, normal
software breaks are used for the internal RAM and ROM areas of an MCU.
Do not set a software break at an address where an address-match interrupt occurs. Otherwise, a user program
may be run out of control. Set a software or hardware break in the top address in address-match interrupt
processing.
When you single step an address where an address-match interrupt occurs, the program stops after executing the
first instruction after returning from address-match interrupt processing.
Note on Accessing Addresses 00000h and 00001h:
With the M16C/Tiny Series MCUs, when a maskable interrupt is generated, the interrupt data (interrupt number
and interrupt request level) stored in addresses 00000h and 00001h are read out. Also, the interrupt request bit is
cleared when address 00000h or 00001h is read out. Consequently, when the address 00000h or 00001h readout
instruction is executed or when address 00000h or 00001h is read out in the cause of a program runaway, a
malfunction occurs in that the interrupt is not executed despite the interrupt request, because the request bit of
the highest priority interrupt factor enabled is cleared.
For this malfunction, when the reading out to address 00000h or 00001h is generated excluding the interrupt,
the WARNING LED (yellow) lights up to alarm. When this LED lights, there is a possibility of read access,
therefore check the user program.
Note on Debugging Operations after Releasing a Reset form the User System:
Do not execute debugging operations (such as stopping the user program execution by an address-match,
software or hardware break, run-time debugging) after releasing a reset on the user system until an interrupt
stack pointer (ISP) is set in the user program.
REJ10J1459-0200 Rev.2.00 Sep 16, 2006
IMPORTANT
4. Hardware Specifications
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