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R01UH0336EJ0102 Rev.1.02
Page 260 of 1538
Jul 17, 2014
V850E2/PG4-L
Section 7 Clock Generation
7.4 Clock Generating Circuit
The structure of the clock generating circuit is described below.
(1)
Structure of Clock Generating Circuit
The circuit consists of the clock oscilation circuit and PLL1.
• Main oscillator circuit (Main OSC)
The clock signal f
X
produced by the main oscillator circuit provides the clock
for the main systems and is input to the PLL. The oscillator circuit requires
the connection of an external resonator between X1 and X2.
• PLL1
The PLL1 circuit generates the clock signal for use in driving the
microcontrollers. The clock signal output from PLL1 is divided by one or two,
and then supplied to peripheral input and output.
Resetting the clock
generating circuit
The clock generator is initialized by a reset from any source other than a
software reset. After release from the reset state, operation is restarted in
accord with the setting of the option byte.