NEC IE-789136-NS-EM1, Руководство пользователя

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CHAPTER 3 INSTALLATION
User’s Manual U14363EJ2V0UM
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3.2 Clock Settings
3.2.1 Overview of clock settings
The system clock to be used during debugging can be selected from (1) to (3) below.
(1) Clock that is already mounted on emulation board
(2) Clock that is mounted by user
(3) Pulse input from target system
If the target system includes a clock oscillator, select either (1) Clock that is already mounted on emulation
board or (2) Clock that is mounted by user . For a clock oscillator, a resonator is connected to the target device
and the target device’s internal oscillator is used. An example of the external circuit is shown in part (a) of Figure 3-2.
During emulation, the oscillator that is mounted on the target system is not used. Instead, the clock that is mounted
on the emulation board that is installed for the IE-78K0S-NS or IE-78K0S-NS-A is used.
If the target system includes an external clock, select (3) Pulse input from target system . For an external clock,
a clock signal is supplied from outside of the target device and the target device’s internal oscillator is not used. An
example of the external circuit is shown in part (b) of Figure 3-2.
Caution The IE system will be hung-up if the system clock is not supplied normally. Moreover, be sure
to input a rectangular wave as the clock from the target. There is no need to supply a clock to
X2 pin.
Figure 3-2. External Circuits Used as System Clock Oscillator
(a) Clock oscillator (b) External clock
X2
X2
Target device
Target device
External
clock
X1
X1
V
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