MC9S08GB60 Datasheet, PDF (102/290 Pages) Motorola, Inc – Microcontrollers

Internal Clock Generator (ICG) Module
7.2.2 Detailed Signal Descriptions
This section describes each pin signal in detail.
7.2.2.1 EXTAL— External Reference Clock / Oscillator Input
If the first write to the ICG control register 1 selected FLL engaged external or FLL bypassed modes, this
signal is the analog external/reference clock or the input of the oscillator circuit. If the first write to the ICG
control register 1 selected FLL engaged internal or self-clocked modes, this signal has no effect on the
ICG.
7.2.2.2 XTAL— Oscillator Output
If the first write to the ICG control register 1 selected FLL engaged external or FLL bypassed modes using
a crystal/resonator reference, this signal is the analog output of the oscillator amplifier circuit. In all other
cases, this signal has no effect on the ICG.
7.2.3 External Clock Connections
If an external clock is used, then the pins are connected as shown below.
ICG
EXTAL
CLOCK INPUT
V_SS
XTAL
NOT CONNECTED
Figure 7-4. External Clock Connections
7.2.4 External Crystal/Resonator Connections
If an external crystal/resonator frequency reference is used, then the pins are connected as shown below.
Recommended component values are listed in Appendix A, “Electrical Characteristics.”
MC9S08GB/GT Data Sheet, Rev. 2.3
102
Freescale Semiconductor