Renesas IE-78044-R-EM, Руководство пользователя

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CHAPTER 4 SETTING CLOCK
This chapter describes how to set the clock.
4.1 Outline of Clock Setting
The main system clock can be selected from any of the following for debugging.
The subsystem clock can only be selected from (2) and (3).
(1) Clock already mounted on the break board
(2) Clock mounted by user
(3) External clock
If the target system is provided with an internal clock, select (1) or (2) , above. The internal clock is the internal oscillator
circuit of the target device. Fig. 4-1 (a) shows an external circuit. The oscillator mounted on the target system is not
used for emulation. Instead, the clock mounted on the break board installed in the IE-78000-R is used.
If the target system is provided with an external clock, select (3) . The external clock is supplied from to the target
device from an external source, and the internal oscillator circuit of the target device is not used. Fig. 4-1 (b) shows the
external circuit.
Caution : An oscillator for a subsystem clock is not mounted on the break board.
To use the subsystem clock either mount an oscillator to the break board or use an external clock.
Fig. 4-1 External Circuits of System Clock Oscillator Circuit
(a) Internal clock (b) External clock
X1 or XT1
X2 or XT2
X1 or XT1
X2 or XT2
Target device
Target device
Extermal
clock
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