D E M O 9 R S 0 8 L A 8
U S E R G U I D E
J A N U A R Y
2 3 ,
2 0 0 8
USB SERIAL LINK
The integrated USB-BDM provides a serial link from the target MCU to the host PC through the
host application. Refer to the P&E Multilink documentation for further details.
LCD
The DEMO9RSO8LA8 provides an 8x21, 168 element, LCD panel connected to the target
MCU. The target MCU provides internal charge-pump and regulated LCD reference. The LCD
contrast is trimmable under MCU control. Refer to the MC9RSO8LA8 Reference
Due to limited IO on the target MCU, several LCD drive signals are multiplexed. Manual for
further details.
USER I/O
User I/O includes 1 buzzer, 2 push button switches, 1 Temperature Sensor, and 1
potentiometer for user I/O. The User1 option header block enables or disables each User I/O
function individually.
Buzzer
The DEMO9RSO8LA8 target board provides an externally modulated piezo-buzzer for audible
applications. A push-pull drive circuit allows the target MCU to easily drive the buzzer at a
center frequency of 2300 Hz. The figure below shows the USER enable position and
associated signal for the buzzer.
Push Button Switches
The DEMO9RSO8LA8 provides 2 push-button switches for user input. Each push-button
switch is configured for active-low operation. No bias is applied to these push-button inputs.
Use of target MCU internal pull-ups is required for proper operation. The figure below shows
the USER enable position and associated signal for each user switch.
Temperature Sensor
A surface-mount thermistor is installed at location RZ1. This component provides a voltage
input to the MCU inversely proportional to temperature. The component used provides a B =
3900.
12