TOP Contributors

  1. MIKROE (2784 codes)
  2. Alcides Ramos (393 codes)
  3. Shawon Shahryiar (307 codes)
  4. jm_palomino (124 codes)
  5. Bugz Bensce (97 codes)
  6. S P (73 codes)
  7. dany (71 codes)
  8. MikroBUS.NET Team (35 codes)
  9. NART SCHINACKOW (34 codes)
  10. Armstrong Subero (27 codes)

Most Downloaded

  1. Timer Calculator (140608 times)
  2. FAT32 Library (73106 times)
  3. Network Ethernet Library (58101 times)
  4. USB Device Library (48266 times)
  5. Network WiFi Library (43846 times)
  6. FT800 Library (43363 times)
  7. GSM click (30393 times)
  8. mikroSDK (29045 times)
  9. PID Library (27125 times)
  10. microSD click (26746 times)
Libstock prefers package manager

Package Manager

We strongly encourage users to use Package manager for sharing their code on Libstock website, because it boosts your efficiency and leaves the end user with no room for error. [more info]

< Back
Library

Keypad_I2c

Rating:

10

Author: dany

Last Updated: 2016-02-18

Package Version: 1.0.0.0

Category: Other Codes

Downloaded: 4237 times

Followed by: 1 user

License: MIT license  

Library for a 4x4 keypad connected to the PIC via an PCF8574 I2c expander (Two I2c lines in stead of 8 I/O pins). This saves a lot of PIC I/O pins.
Permits also small PIC's (with low pin count) to control a keypad.

No Abuse Reported

Do you want to subscribe in order to receive notifications regarding "Keypad_I2c" changes.

Do you want to unsubscribe in order to stop receiving notifications regarding "Keypad_I2c" changes.

Do you want to report abuse regarding "Keypad_I2c".

  • Information
  • Comments (3)

Library Blog

"Keypad_I2c" is a library to connect an 4x4 keypad via I2c to the PIC, using a PCF8574 expander. It uses the PCF8574 library.

In contradiction with the 4x4 keypad library from mE (connection via 8 I/O pins to the PIC), this version does not require pull down resistors (the internal ones of the PCF8574 are used in stead).

The functionality is the same as that of the mE (parallel connections) library, plus one addition: the function Keypad_I2c_PCF8574_Key_Status. It returns 16 bits (one word) with the status of all keys in the keypad: Key1 = bit 0; Key2 = bit 1;...; Key16 = bit 15. A bit with the value "1" is pressed, "0" is not pressed.

Have fun!

----------------------------------------------------------------------------------------------------------------------------------------------

2013-03-18: original version.

Connection diagram

Connection diagram

Connection Diagram for a 4x4 keypad. If there are less keypad columns or rows, then the free PCF8574 line(s) should be left unconnected.

View full image

-----------------------------------------------------------------------------------------------------------------------------------------------
2013-03-19: added the function Keypad_I2c_PCF8574_Key_Status.
It returns 16 bits (one word) with the status of all keys in the keypad:
Key1 = bit 0; Key2 = bit 1;...; Key16 = bit 15.
A bit with the value "1" is pressed, "0" is not pressed

-----------------------------------------------------------------------------------------------------------------------------------------------

2013-03-21: removed an omission in the example for the Keypad_I2c library: the call to "Soft_I2c_Init" was forgotten (still, it worked!).

---------------------------------------------------------------------------------------------------------------------------------------------
2013-03-25: Replaced the mikroBasic package files. The target compiler in them was still mikroPascal. Sorry for the inconvenience.

----------------------------------------------------------------------------------------------------------------------------------------

2014-03-13: The mikroBasic files and zip files have been updated. All mB sources are present now (not tested if compilable though).


2015-01-26: Replaced the mB files: all mB files are compilable now (which e.g. means that all "with" statements are dealt with). I could however not link and test the libraries (no mB licence).

ALSO FROM THIS AUTHOR

Utilities

26

Several utility libraries: - String Utilities, - SDMMC Utilities, - Bit Utilities, - (standard) Pascal Funtions, - Assert functions, - UartUtils, - Button utilities. - CRC routines

[Learn More]

Tool: Function Calls Display

10

Shows the function calls of the project in a number of views (a.o. graphical tree).
For mP, mC and mB for PIC and dsPIC.

[Learn More]

Article: Record Member alignment for PIC24/dsPIC and PIC32

1

Describes how record members are stored internally in their records, and what problems to expect if that is not taken into account.

[Learn More]