need help interfacing pic16f877+4x3keypad + LCD

hello there i need help how to interface the LCD 4x3keypad and a pic16f877a.
im using 74c922 keypad decoder. The LCD already initialized and display messages but i need to INPUT NUMERIC CHARACTER FROM THE KEYPAD TO THE LCD DISPLAY, i tried but nothing had displayed when i press a key.

thankx.

hello,

you must try first to disect or testing the output of pin D1,D2,D3
if there is an equivalent digital combinations for the desired characters
1.
say " R" try to test pins 17,16,15,13, for D's output
2.
next say if you have proper capacitance in the debounce input
3. then also check the enable pin's out put

after that ..if you are certain of those combinations try it now to LCD


try to visit this site pls..


http://www.parallax.com/dl/docs/cols/nv/vol4/col/nv97.pdf#search='74c922'

basic stamp programming would seem similar to pIC877

thanks

Cyrix-Cracker

Added after 2 minutes:


hello,

you must try first to disect or testing the output of pin D1,D2,D3
if there is an equivalent digital combinations for the desired characters
1.
say " R" try to test pins 17,16,15,13, for D's output
2.
next say if you have proper capacitance in the debounce input
3. then also check the enable pin's out put

after that ..if you are certain of those combinations try it now to LCD


try to visit this site pls..


http://www.parallax.com/dl/docs/cols/nv/vol4/col/nv97.pdf#search='74c922'

basic stamp programming would seem similar to pIC877

thanks

Cyrix-Cracker

Thanks for your help..
i dont understand the code, we program it in .asm not in basic or c

i have used this chip a few years ago.

try polling for the DATA Available before reading data from the chip.

hi, c and asm
are not different

both are language to a machine


compare thier syntax and structure

data declarations
variable
addressing
interrupts

directives

there you can migrate whatever languages
it is just a will and dedications to learn all this

...

thanks

Cyrix-Cracker