Interfacing a membrane keypad in an LCD using microcontroller

[jmac.pi]

hello.

what would be the best way to interface a keypad in an LCD using an MCU (PIC16F877A)?

i'll be interfacing 5 - 7 keypads, so will it be ok using an MM74C922 encoder considering the cost for the additional MM74C922 ?

i would like to hear other methods about interfacing keypads in LCDs using MCU.
all comments are welcome. thanks. ^^

 

[Nigel Goodwin]

It seems a total waste adding an extra IC, check my PIC tutorials for scanning a matrix keypad - it's a simple process.

 

[jmac.pi]

ohh.. thanks for the tutorial.. appreciate it.

btw, is it possible to interface a keypad to 2 or 3 or more LCDs using 1 MCU ?
i'm using a PIC16F877A. what i want to do next is, i want to input different data and
interface those data in their corresponding LCDs. for example, using 1 keypad, 1 mcu, and 3 LCDs

input data1
interface data1 in LCD1
input data2
interface data2 in LCD2
input data3
interface data3 in LCD3

that sort of thing. i wonder if it is possible. thanks. ^^

 

[Nigel Goodwin]

Yes, just a question of having multiple LCD's connected - and they can share many of the pin connections, just select the one you want.