Renesas M16C/64, Руководство пользователя

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R0E530640MCU00 User’s Manual 2. Setup
REJ10J1733-0100 Rev.1.00 Apr. 01, 2008
Page 32 of 229
2.8.3 Using the Oscillator Circuit on the User System
To operate this product with an external clock, construct the oscillator circuit as shown in Figure 2.8 in the user system and
input the oscillator output at 50% duty (within the operating range of the evaluation MCU) into pin X
IN
. And pin X
OUT
should
be open. Choose "User" in the emulator debugger to use this clock.
Figure 2.8 External oscillator circuit
Make note that in the oscillator circuit shown in Figure 2.9 where an oscillator is connected between pins X
IN
and X
OUT
,
oscillation does not occur because a converter board and other devices are used between the evaluation MCU and the user
system. It is the same for sub-clock oscillator circuits (X
CIN
and X
COUT
).
Figure 2.9 Circuit in which oscillation does not occur
2.8.4 Using the Internal Generator Circuit
The dedicated circuit in the E100 can generate any arbitrary frequency specified by the emulator debugger, and it can be
supplied as a main clock. It does not depend on either the oscillator circuit board in the MCU unit or the oscillator circuit on
the user system. If you want to debug programs without the user system or change a frequency temporarily, you can check its
operation before purchasing an oscillator. If you want to use the internal generator circuit in the E100 as a main clock, choose
"Generate" in the emulator debugger and specify a frequency you like to use this clock.
Although you can change a frequency between 1.0 and 99.9 MHz by 0.1 MHz for the E100, do not specify a value exceeding
the maximum input frequency 20 MHz of the X
IN
of the MCU.
IMPORTANT
Note on Using the Internal Generator Circuit:
z The internal generator circuit is equipped for temporary debugging purposes. Temperature characteristics of
frequencies are not guaranteed.
z Be sure to evaluate your system with an oscillator whose frequency is the same as that of the oscillator module
or oscillator circuit (emulator) for final evaluation purposes.