NEC IE-784937-NS-EM1, Руководство пользователя

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CHAPTER 3 INSTALLATION
User’s Manual U16556EJ1V0UM
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(3) External clock
An external clock connected to the target system can be used via an emulation probe.
Figure 3-5. When Using an External Clock
Clock generator
(to be used)
IE-78K4-NS
IE-784937-NS-EM1
Emulation probe
Target system
Remark The clock supplied by the target system’s clock generator (encircled in the figure) is used.
3.3.2 Main system clock settings
Table 3-1. Main System Clock Settings
IE-784937-NS-EM1 Frequency of Main System Clock
Parts Board (UMCLK)
CPU Clock Source
Selection (ID78K4-NS)
When using clock that is
already mounted on
emulation board
12.580 MHz Oscillator used
When using clock mounted
by user
Oscillator assembled by user
Internal
When using external clock
Other than 12.580 MHz
Oscillator not used External
Caution When using an external clock, open the configuration dialog box when starting the integrated
debugger (ID78K4-NS) and select “External” in the area (Clock) for selecting the CPU’s clock
source (this selects the user’s clock).
Remark The IE-784937-NS-EM1’s factory settings are those listed above under “when using clock that is already
mounted on emulation board”.
(1) When using clock that is already mounted on emulation board
When the IE-784937-NS-EM1 is shipped, a 12.580 MHz crystal oscillator is already mounted in the IE-784937-
NS-EM1’s UMCLK socket. When using the factory-set mode settings, there is no need to make any other
hardware settings.
When starting the integrated debugger (ID78K4-NS), open the configuration dialog box and select “Internal” in
the area (Clock) for selecting the CPU’s clock source (this selects the emulator’s internal clock).