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DEMO9S08QE8 User Manual
7.8
Analog Input Potentiometer
The DEMO9S08QE8 provides an easy access 10Kohm potentiometer whose
output may be connected to PTC6 and/or PTA0, selectable by J21, POT_EN.
7.8.1
J21 - Potentiometer Output Selection Jumpers POT_EN
Selects the potentiometer output connection. By default it is
connected to PTA0.
Figure 7-17: Potentiometer Output Selection Jumpers POT_EN (J21)
7.9
Optional External Crystal Circuitry Jumper Enable
The DEMO9S08QE8 provides external crystal circuitry without components
populated. A user may elect to populate the components, and may use
jumper J17, CLOCK_EN, to enable the external crystal circuitry.
7.9.1
J17 - External Crystal Circuitry Enable Jumpers CLOCK_EN
Enables or disables the external crystal circuitry. Both positions must
be installed to enable use of crystal circuitry.
Figure 7-18: External Crystal Circuitry Enable Jumper CLOCK_EN (J17)
7.10
Optional Jumpers For Various VDD And VSS
The DEMO9S08QE8 provides 5 jumpers, J22 through J25, for different VDD
and VSS connections on the bottom of the board. By default, they are not
populated and are shorted correspondingly with zero-ohm resistors in parallel,
except J24 which is populated. A user may take off the zero-ohm resistor and
install a corresponding jumper.
Note:
JR2 (Jumper 23) and JR5 (Jumper 26) have no efffect on QE8 devices.
