NEC IE-703242-G1-EM1, Preliminary User'S Manual

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Chapter 2 Name and Functions of Components
Preliminary User’s Manual U16345EE1V0UM00
2.5 Clock Operation
This chapter describes the operation of the clock generation of IE-703242-G1-EM1. The V850ES/GB1
features two clock oscillators: a main clock oscillator for normal operation and a sub clock oscillator that
allows to run the microcontroller at a slow operation speed to implement certain power save functions.
2.5.1 Main Clock
The main clock oscillator of the V850ES/GB1 and also IE-703242-G1-EM1 operates at frequencies up
to 16 MHz. On the emulation board the source for the main clock can either be a crystal or a dedicated
C-MOS oscillator. By default a crystal is used which is assembled to the respective connector (CN6).
Alternatively a dedicated C-MOS oscillator in DIL Package may be used. In this case the crystal and
capacitors must be removed from CN6 and a crystal oscillator must be mounted to socket SO1.
Figure 2-4: Main Clock Configuration
Caution: Since the clock inputs X1 and X2 of the I/O chip are not connected to the target, crys-
tal or oscillator operation from the target board is not possible. Crystal or Oscillator
provided on the emulation board must be used.
X1
X2
SO1
CN6
Venus
I/O chip