S3F84B8_UM_REV 1.00
7 CLOCK CIRCUIT
7-3
MUX
Selected
OSC
Noise
Filter
Oscillator
Wake-up
Oscillator
Stop
CLKCON.7
INT Pin
CLKCON.4-.3
1/2
1/16
M
U
X
Stop
Instruction
CPU Clock
Internal RC
Oscillator (8MHz)
Internal RC
Oscillator (0.5 MHz)
External
Crystal/Ceramic
Oscillator
NOTE:
An external interrupt (with RC-delay noise filter ) can be used to release stop mode
and "wake-up" the main oscillator .
In the S3F84B8, the INT0-INT5 external interrupts are of this type .
Smart Option
(3F.1-0 in ROM)
1/8
External RC
Oscillator
Figure 7-4 System Clock Circuit Diagram