Configuration; Clock Output Function; Clock Generator - NEC Renesas V850/SC1 User Manual

4.2 Configuration

FRC
XT1
Subclock
oscillator
XT2
X1
Main clock
oscillator
X2
STP,
MCK
CLKOUT

4.3 Clock Output Function

This function outputs the CPU clock via the CLKOUT pin.
When clock output is enabled, the CPU clock is output via the CLKOUT pin. When it is disabled, a low-level signal
is output via the CLKOUT pin.
Output is stopped in the IDLE or STOP mode (fixed to low level).
This function is controlled via the DCLK1 and DCLK0 bits in the PSC register.
A high-impedance status is set during the reset period. After reset is canceled, a low level is output.
Caution While CLKOUT is being output, changing the CPU clock (CK2 to CK0 bits of PCC register) is
disabled.
CHAPTER 4 CLOCK GENERATION FUNCTION
Figure 4-1. Clock Generator
f
XT
IDLE
IDLE
Prescaler
control
f
XX
f /2 f /4
XX XX
Prescaler
User's Manual U15109EJ3V0UD
IDLE
control
CK2 to CK0
HALT
f
XT
f /8
XX
Selector
Clock supplied to
watch timer, etc.
CPU clock
HALT
(f )
control
CPU
Clock supplied to
peripheral hardware
121