Clock Settings; Overview Of Clock Settings - NEC IE-178048-NS-EM1 User Manual

3.2 Clock Settings

3.2.1 Overview of clock settings

The main 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) External clock
If the target system includes an internal clock, select either (1) Clock that is already mounted on emulation
board or (2) Clock that is mounted by user. For an internal clock, the target device is connected to a resonator
and the target device's internal oscillator is used. An example of the external circuit is shown in part (a) of Figure 3-3.
During emulation, the resonator that is mounted on the target system is not used. Instead, it uses the clock that is
mounted on the emulation board which is connected to the IE-78K0-NS or IE-78K0-NS-A.
If the target system includes an external clock, select (3) External clock.
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 3-3.
Caution The IE system will be hung-up if the main 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 3-3. External Circuits Used as System Clock Oscillator
(a) Internal clock
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CHAPTER 3 INSTALLATION
Target device
External
X1
clock
X2
User's Manual U15928EJ1V0UM
(b) External clock
Target device
X1
X2