NEC IE-784937-NS-EM1, Руководство пользователя

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CHAPTER 3 INSTALLATION
User’s Manual U16556EJ1V0UM
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3.2 Selection of Emulator Main Unit
JP3 in the IE-784937-NS-EM1 must be set in accordance with the emulator main unit to be used as follows.
Using IE-784937-NS-EM1 in combination with IE-78K4-NS: Short 1 and 2 (shipment setting)
Using IE-784000-R in combination with IE-784937-NS-EM1 and IE-78K4-R-EX3: Short 2 and 3
3.3 Clock Settings
3.3.1 Overview of clock settings
The main system clock to be used during debugging can be selected from (1) to (3) below, and the timer clock
from (1) and (2) 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 3-2. 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 installed for the IE-78K4-NS.
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 3-2.
Figure 3-2. External Circuits Used as System Clock Oscillator
(a) Internal clock (b) External clock
X2 or XT2 X2 or XT2
Target device Target device
External
clock
X1 or XT1
X1 or XT1