Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
Hi,
here is a project for keypad lock for electronic door, using 16f84,
but you may easy adapt this for 16f877,
also you have asm code, with very small corection this will be work on 877,
if you have problem mail me, I will help you,
regards
i am the begener for pic just 1year exp. not so much knlg but i will try to convert it
but still if one have the subrutine for it , that is best option for me.
thank you again
keyread
bsf portb,4
takes the port line high
btfsc porta,ret1
check to see it a key has been pressed and return line 1 is high
goto r1c1
if so goto row1coloum1 press detected
btfsc porte,ret2
check to see it a key has been pressed and return line 2 is high
goto r1c2
if so goto row1coloum2 press detected
.
.
so on and so forth
r1c1 bcf portb,4
clear the high bit to low
movlw 07h
since row 1 and column 1 value is 7
return
return 7 in W
This code is for 4x4 matrix. For each scan line going high, all 4 returns lines are tested. If the return lines are detected to be high, then the appropriate code is returned.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
