Ports and Connectors, Lcdport, Keypad, Gnd

PORTS AND CONNECTORS

LCD_PORT

The LCD_PORT interface is connected to the data bus and memory mapped to locations BF0

–BFF hex assigned to CS7. For the standard display, address BF0 is the Command register, address BF1 is the Data register.

The interface supports all OPTREX™ DMC series displays in 8 bit bus mode with up to 80 characters and provides the most common pinout for a dual row rear mounted display connector. Power, ground, and Vee are also available at this connector.

+5V	2	1	GND
A0	4	3	LCD-Vee
LCD1	6	5	/RW
D9	8	7	D8
D11	10	9	D10
D13	12	11	D12
D15	14	13	D14

Command Register: $BF0

Data Register:

$BF1

LCD-Vee is supplied by U13 and is adjusted by the CONTRAST Potentiometer (adjustable resistor).

See the file KLCD12D6.ASM for an example program using this LCD connector.

	J3
LCD3	2	1
	4	3

LCD2

LCD4

Additional lines can be used as enables for larger panels and are mapped as:

LCD2 = $BF4 & $BF5	LCD4 = $BFC & $BFD
LCD3 = $BF8 & $BF9

KEYPAD

1PH0

2PH1

3PH2

4PH3

5PH4

6PH5

7PH6

8PH7

The KEYPAD connector is a passive 8-pin connector that can be used to connect a 4 x 4 matrix (16 key) keypad device. The connector is mapped to HC12 I/O port H. This interface is implemented as a software keyscan. Pins PH0-3 are used as column drivers which are active high outputs. Pins PH4-7 are used for row input and will read high when their row is high.

See the file KLCD12D6.ASM for an example program using this connector.