NEC IE-789026-NS-EM1, Руководство пользователя

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CHAPTER 3 INSTALLATION
User’s Manual U14362EJ2V1UM
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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) 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 the 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 installed in 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 the 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 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 the X2 pin.
Figure 3-2. External Circuits Used as System Clock Oscillator
(a) Clock oscillator (b) External clock
X1
V
SS
External
clock
X2
X1
X2
Target device Target device