CCS C Software and Maintenance Offers
FAQFAQ   FAQForum Help   FAQOfficial CCS Support   SearchSearch  RegisterRegister 

ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

CCS does not monitor this forum on a regular basis.

Please do not post bug reports on this forum. Send them to CCS Technical Support
4 x 4 keyboard matrix

 
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion
View previous topic :: View next topic  
Author Message
steppermotor



Joined: 24 Oct 2010
Posts: 10

View user's profile Send private message

4 x 4 keyboard matrix
PostPosted: Fri Oct 29, 2010 6:35 pm     Reply with quote
I'm trying to interface a 4x4 keyboard matrix to a PIC16F877A, I was wondering does anyone know which pins on this keypad are the row and which are the columns the data sheet is unclear about this.

http://datasheet.octopart.com/96BB2-006-F-Grayhill-datasheet-46283.pdf
PCM programmer



Joined: 06 Sep 2003
Posts: 21708

View user's profile Send private message

PostPosted: Fri Oct 29, 2010 8:07 pm     Reply with quote
Looking at the back of the keypad, the pins are numbered like this:
Code:

8 7 6 5 4 3 2 1

These are the pin assignments:
Code:

Pin   Function 
 1    Row 1
 2    Row 2
 3    Row 3
 4    Row 4
 5    Col 1
 6    Col 2
 7    Col 3
 8    Col 4

Remember to put 10K pullup resistors on the Row pins.
John P



Joined: 17 Sep 2003
Posts: 331

View user's profile Send private message

PostPosted: Sat Oct 30, 2010 11:18 am     Reply with quote
Unless you use Port B and have the internal pullups enabled.
Display posts from previous:   
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group