Ports and connectors, Lcd_port, Keypad – Motorola MCU 68HC912D60 User Manual

Page 12

Advertising
background image

12

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

LCD2

4

3

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

1

PH0

2

PH1

3

PH2

4

PH3

5

PH4

6

PH5

7

PH6

8

PH7

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.

Advertising
This manual is related to the following products: