Renesas M16C/64 Network Card User Manual


 
R0E530640MCU00 User’s Manual 7. Hardware Specifications
REJ10J1733-0100 Rev.1.00 Apr. 01, 2008
Page 223 of 229
IMPORTANT
Note on Clock Supply to the MCU:
z A clock supplied to the evaluation MCU is selected by the Emulator tab in the Init dialog box of the emulator
debugger.
(1) When "Emulator" is selected:
A clock generated by the oscillator circuit board on the MCU unit is supplied. It is continually supplied
regardless of the status of the user system clock and that of the user program execution.
(2) When "User" is selected:
A clock generated by the oscillator in the user system is supplied. It depends on the status of the oscillation
(on/off) of the user system.
(3) When "Generated" is selected:
A clock generated by the dedicated circuit in the E100 is supplied. It is continually supplied regardless of
the status of the user system clock and that of the user program execution.
Note on Stop and Wait Modes:
z Do not single step an instruction shifting to stop or wait mode. It may cause communication errors.
Note on the Watchdog Function:
z If the reset circuit of the user system has a watchdog timer, disable it when using the emulator.
Note on Protect Register:
z The protect is not canceled when bit 2 of protect register PRCR (PRC2), which enables writing into the port P9
direction register and the SI/Oi control register, is changed with the below procedure.
(1) Step execution of an instruction setting PRC2 to "1"
(2) Setting a break point between an instruction setting PRC2 to "1" and a point where the port P9 direction
register or the SI/Oi control register is set
(3) Setting PRC2 to "1" by the Memory window or Command Line window
Note on Access Prohibited Area:
z You cannot use internally reserved areas. Write signals to the areas will be ignored, and values read will be
undefined.
Note on Breaks:
z The area displaying break points in the program window of the emulator debugger shows the following breaks.
(1) Software break
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.
(2) Hardware break
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.
(3) Exceptional event
This is a debugging function which stops a program by an abnormal operation of the user program or
overflow of each function’s measurement counter, etc.
Notes on Software Breaks:
z The BRK instruction can be used for the emulator only. You cannot use it in a user program. As BRK
instruction interrupt vector is used by the emulator system, the read data is different from expected value.
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.