User`s manual

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IMPORTANT
Note on Breaks:
z The area displaying break points in the program window of the emulator debugger shows the following
breaks.
(1) Address-match break "A"
This is a debugging function which breaks a program, using the address-match interrupt function of
the MCU, immediately before the system executes an instruction at a specified address. The
instruction at the preset address will not be executed.
(2) Software break "B"
This is a debugging function which generates a BRK interruption by changing an instruction at a
specified address to a BRK instruction (00h) to break a program immediately before the system
executes an instruction at a specified address. The instruction at the preset address will not be
executed.
(3) Hardware break "H"
This is a debugging function which breaks a program by setting the detection of an execution of an
instruction at a specified address as a break event. The program will break after the instruction at
the specified address is executed.
Notes on Address-Match Breaks:
z As the processing speed of setting and canceling address-match breaks is relatively fast, you can save
the times of writing into the internal flash ROM of an MCU. Therefore, address-match breaks precede
the other breaks when setting breakpoints in the internal flash ROM area of an MCU.
z Address-match breaks can be set only in RAM and ROM areas of an MCU.
z Address-match breaks can be set at up to 8 points. The other breaks are set as software breaks.
z Address-match breaks can be set or canceled even when the user program is being executed.
Notes on Address-Match Interrupts:
z 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.
z 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.
z 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.
Notes on Software Breaks:
z Software breaks change the instruction at a specified address to a BRK (00h). Therefore, take note that
when you reference the result of a trace in bus mode, "00h" is displayed.
z The BRK instruction can be used for the emulator only. You cannot use it in a user program.
z You can neither set nor cancel a software breakpoint in the internal ROM area of an MCU during user
program execution, while you can set or cancel it in the internal RAM area of an MCU and the area
(emulation memory) where the map setting is INTERNAL in chip-select CS3* to CS0*.