User`s manual

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6.6. Audio (Audio Out, Mic, Speaker, Volume Potentiometer)
An amplified stereo audio output jack is provided and connected to the timer circuit. TIOCA8A is used for Right audio
channel and comes out on CPU pin 64. TIOC8B is used for the Left audio channel and comes out on CPU pin 63. The
stereo amp is powered by a National Semi LM4808. An on-board Analog Devices Inc. (ADI) Silicon microphone
(ADMP401) is connected to the ADC channel AN5 (CPU pin 89) using an ADI SSM2167 low voltage Microphone
preamplifier. A single turn potentiometer is connected to the ADC channel AN4 (CPU pin 90) of the microcontroller. This
may be used to vary the input analog voltage value to this pin between 3V3A and Ground. The potentiometer is used as
a volume control in the Demo Application. Note that the default is to have JP7, SPK EN, fitted. This enables the
on-board Star Micronics speaker. Removing this jumper disables the on-board speaker. Remove the jumper to use
the headphone audio jack.
Note: The potentiometer is fitted to offer an easy way of supplying a variable analog input to the controller. It does not
necessarily reflect the accuracy of the controllers ADC. Please see the device manual for details.
6.7. Serial port
The Serial module allows the MCU to communicate to a Host PC through the RS-232 connector, J5, using RS232Rx and
RS232Tx. The serial port is configured in DCE mode allowing direct connection to a PC without a Null modem. The serial
module can also be used as a serial debug port. Table 6-4 contains details of the specific pin functions and their
locations.
Description Function MCU Pin Connector Pin
TXD2 Serial Transmission Pin 44 J5.2
RXD2 Serial Reception Pin 42 J5.3
Table 6-4: Serial port pin details
6.8. RCAN
The RCAN module can be controlled by the MCU through the CTx0 (Port pin P32) and CRx0 (Port pin P33) lines, or
controlled externally through the header connections CTx0 and CRx0. The Table 6-5 contains details of the specific pin
functions and their locations. Note that an 8 pin Renesas R2A25416SP CAN transceiver is fitted to the board.
Description Function MCU Pin Header Pin
CTx0 RCAN Transmission Pin 18 CAN High J6.1
CRx0 RCAN Reception Pin 17 CAN Low J6.3
Table 6-5: RCAN port pin details
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