XC68HC08KH12 Motorola, XC68HC08KH12 Datasheet - Page 99

• Manufacturer Part Number: XC68HC08KH12
• Description: MICROCONTROLLER
• Manufacturer: Motorola

8.5.6 Buffered Crystal Clock Output (CGMVOUT)
8.5.7 CGMVSEL
8.5.8 Oscillator Enable Signal (SIMOSCEN)
8.5.9 Crystal Output Frequency Signal (CGMXCLK)
8.5.10 CGM Base Clock Output (CGMOUT)
8.5.11 CGM CPU Interrupt (CGMINT)
MC68HC(7)08KH12
MOTOROLA
—
Rev. 1.0
CGMVOUT buffers the OSC1 clock for external use.
CGMVSEL must be tied low or floated.
The SIMOSCEN signal comes from the system integration module (SIM)
and enables the oscillator and PLL.
CGMXCLK is the crystal oscillator output signal. It runs at the full speed
of the crystal (f
Figure 8-2
OSC2 and may not represent the actual circuitry. The duty cycle of
CGMXCLK is unknown and may depend on the crystal and other
external factors. Also, the frequency and amplitude of CGMXCLK can be
unstable at startup.
CGMOUT is the clock output of the CGM. This signal goes to the SIM,
which generates the MCU clocks. CGMOUT is a 50 percent duty cycle
clock running at twice the bus frequency. CGMOUT is software
programmable to be either the oscillator output, CGMXCLK, divided by
two or the VCO clock, CGMVCLK, divided by two.
CGMINT is the interrupt signal generated by the PLL lock detector.
Clock Generator Module (CGM)
shows only the logical relation of CGMXCLK to OSC1 and
XCLK
) and comes directly from the crystal oscillator circuit.
Clock Generator Module (CGM)
Advance Information
I/O Signals
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