AN1921 Motorola / Freescale Semiconductor, AN1921 Datasheet - Page 21

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

A.7 Interfacing the LCD+
A.8 Keypad Interface
A.9 Keypad Options
The LCD+ can be controlled using any computer or microprocessor supporting 1200-57600 baud data
rates with a 8,N,1 data format (8 data bits, No parity, 1 stop bit).
The keypad interface supports matrix keypads up to 4x4 in size (16 keys). Instead of predefining the
keypad key serial data format as 0 through 15, each of the keypad’s keys is serially represented by a
user-definable byte value. This user-definable value (Tag) is stored within the LCD+ EEPROM as a
0-15 byte array. Each byte of the array corresponds to a key on the keypad (i.e. key 0 corresponds to
byte 0 of the array). Whenever a key is pressed, the stored byte representation for that key number is
sent serially.
Various keypad options are supported by six user-definable options or modes. To set these modes,
send a CTRL-X, followed by your command byte containing the desired modes. As shown in
Table
Codes for the LCD+ are shown in
A-2, placing a 1 in any of the bits turns its corresponding option on, and a 0 turns it off. Control
Interface Examples Using the Embedded SDK
Figure A-1. LCD+ Pin-Outs
Table
A-3.
Integrating Devices With the EVM Board
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