AN1921 Motorola / Freescale Semiconductor, AN1921 Datasheet - Page 20

• Manufacturer Part Number: AN1921
• Description: AN1921 General DSP568xx Interface Examples using the Embedded SDK
• Manufacturer: Motorola / Freescale Semiconductor

Integrating Devices With the EVM Board
Appendix A.
A.1 Pin Definitions
A.2 Serial I/O
A.3 Power Input
A.4 ADC Inputs
A.5 Relay Driver Outputs
A.6 Matrix KeyPad Input
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The Serial LCD+ is a 4x20 LCD display with a built-in bi-directional serial interface. The unit is
controlled using standard RS-232 serial signals from a host computer or micro-controller. The LCD+
supports the following serial data rates: 1200, 2400, 4800, 9600, 19200, 38400, and 57600 baud.
Figure A-1
definitions are denoted.
The serial I/O header is made up of five connections;
The power input section consists of four through holes (Solder pads). The two holes marked GND are
grounds. The hole marked +5.5V to +15V is tied to the LCD+ module’s onboard regulator. The hole
marked +5V ties to the +5V buss and is used to bypass the LCD+ onboard regulator when a regulated
+5V source is supplied.
The eight ADC inputs are labeled 1 – 8. By default, all ADC inputs are set to read voltage in the 0 to
+5V range.
There are nine Relay Driver connections, labeled on the underside of the board as R1-8 and
RLY_VDC. The connections labeled R1-8 are the relay driver chip outputs; the RLY+VDC
connection provides access to the ULN2803A driver chip’s internal back EMF protection diodes.
The keypad input connections (visible in
connection. The lower eight of the 8x2 header connection (not visible in
factory for programming and should remain unconnected.
shows a top down of the LCD+ (the view with the LCD display module removed). The pin
Pin #
1
2
3
4
5
Interface Examples Using the Embedded SDK
Details of NewMedia’s Serial LCD+
TX serial output - nearest to top in Figure 1
RX serial input – next pin below TX
Not connected
GND – connected to host comp/ c serial ground
A courtesy +5V courtesy connection (max 20 mA)
Table A-1. Serial I/O pin definitions
Figure
A-1) are the upper-most eight of the 8x2 header
Description
Table A-1
defines the pins.
Figure
A-1) are used by the