MC68HC05B4 Datasheet, PDF (39/298 Pages) Motorola, Inc – High-density Complementary Metal Oxide Semiconductor (HCMOS) Microcomputer Unit

2.5.5 TCAP2
The TCAP2 input controls the input capture 2 function of the on-chip programmable timer system.
2
2.5.6 TCMP1
The TCMP1 pin is the output of the output compare 1 function of the timer system.
2.5.7 TCMP2
The TCMP2 pin is the output of the output compare 2 function of the timer system.
2.5.8 OSC1, OSC2
These pins provide control input for an on-chip oscillator circuit. A crystal, ceramic resonator or
external clock signal connected to these pins supplies the oscillator clock. The oscillator frequency
(f_OSC) is divided by two to give the internal bus frequency (f_OP). There is also a software option
which introduces an additional divide by 16 into the oscillator clock, giving an internal bus
frequency of f_OSC/32.
2.5.8.1 Crystal
The circuit shown in Figure 2-5(a) is recommended when using either a crystal or a ceramic
resonator. Figure 2-5(d) lists the recommended capacitance and feedback resistance values. The
internal oscillator is designed to interface with an AT-cut parallel-resonant quartz crystal resonator
in the frequency range specified for f_OSC (see Section 11.4). Use of an external CMOS oscillator
is recommended when crystals outside the specified ranges are to be used. The crystal and
associated components should be mounted as close as possible to the input pins to minimise
output distortion and start-up stabilisation time. The manufacturer of the particular crystal being
considered should be consulted for specific information.
2.5.8.2 Ceramic resonator
A ceramic resonator may be used instead of a crystal in cost sensitive applications. The circuit shown
in Figure 2-5(a) is recommended when using either a crystal or a ceramic resonator. Figure 2-5(d) lists
the recommended capacitance and feedback resistance values. The manufacturer of the particular
ceramic resonator being considered should be consulted for specific information.
MC68HC05B6
Rev. 4
MODES OF OPERATION AND PIN DESCRIPTIONS
TPG
MOTOROLA
2-11