HCS08 datasheet(86/290 Pages) MOTOROLA

86 / 290 page

Internal Clock Generator (ICG) Module

MC9S08GB/GT

MOTOROLA

6.2.2 Detailed Signal Descriptions

This section describes each pin signal in detail.

6.2.2.1 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.

6.2.2.2 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.

6.2.3 External Clock Connections

If an external clock is used, then the pins are connected as shown below.

Figure 6-4 External Clock Connections

Table 6-1 Signal Properties

Name

Function

Reset State

EXTAL

External clock/oscillator input

Analog input

XTAL

Oscillator output

Analog output

ICG

XTAL

EXTAL

VSS

CLOCK INPUT

NOT CONNECTED

HCS08 데이터시트(PDF) 86 Page - Motorola, Inc