I2C PortExpander - MCP23017 - library and examples

[yo2lio]

I2C PortExpander library for MCP23017.

This library is tested on EasyPIC4 board, PIC16F877A, PIC18F452 MCU and home made MCP23017 board, made by me.

First: copy i2cportexpander_lib_p16.mcl file in dir ../uses/P16 and i2cportexpander_lib.mcl file in dir ../uses/P18.

Library include :

Code: Select all

sub procedureI2CExpander_Init(dim byref RstPort as byte, dim RstPin, ModuleAddress as byte)
'I2C_Init(100000) must be called before initializing I2C Port Expander'

sub function I2CExpander_Read_Byte(dim ModuleAddress, RegAddress as byte) as byte

sub procedureI2CExpander_Write_Byte(dim ModuleAddress, RegAddress, Data as byte)

sub procedureI2CExpander_Set_Mode(dim ModuleAddress, Mode as byte)

sub procedureI2CExpander_Read_ArrayPortA(dim ModuleAddress, NoBytes as byte, dim byref DestArray as byte[100])

sub procedureI2CExpander_Read_Array(dim ModuleAddress, StartAddress, NoBytes as byte, dim byref DestArray as byte[100])

sub procedureI2CExpander_Write_Array(dim ModuleAddress, StartAddress, NoBytes as byte, dim byref SourceArray as byte[100])

sub function I2CExpander_Read_PortA(dim Address as byte) as byte

sub function I2CExpander_Read_PortB(dim Address as byte) as byte

sub procedureI2CExpander_Read_ArrayPortB(dim ModuleAddress, NoBytes as byte, dim byref DestArray as byte[100])

sub procedureI2CExpander_Write_PortA(dim ModuleAddress, Data as byte)

sub procedureI2CExpander_Write_PortB(dim ModuleAddress, Data as byte)

sub procedureI2CExpander_Set_DirectionPortA(dim ModuleAddress, Data as byte)

sub procedureI2CExpander_Set_DirectionPortB(dim ModuleAddress, Data as byte)

sub procedureI2CExpander_Set_PullUpsPortA(dim ModuleAddress, Data as byte)

sub procedureI2CExpander_Set_PullUpsPortB(dim ModuleAddress, Data as byte)

You can download code and example for P16 and P18 MCU from:
http://www.microelemente.ro/MikroBasic/ ... pander.zip

Source code of library is available in MikroPascal language:
http://www.microelemente.ro/I2CPortExp_Source.zip

[kostasgr]

Hello!

Is there any posibility to have a code snippet that puts all portA pins output 1?
I tried to do it but it didn't worked. I did set the portA as output and written %11111111 but nothing happens.

Thx:)

[yo2lio]

Hi,

Unfortunately this library is old and now I can't offer support for them (I don't have time for this).

But you have source code in MikroPascal language : http://www.microelemente.ro/MikroPascal ... Source.zip

[oliverb]

Was the SPI Port Expander source ever published?

I'm curious because I started writing my own version, partly because of the lack of source, mainly to see if the reset pin is really needed?

IMO Reset isn't needed and could be tied to supply, the device can be forced into a known state via software. Currently I can't prove this.

[yo2lio]

Was the SPI Port Expander source ever published?

Unfortunately this library is old and now I can't offer support for them (I don't have time for this).

But you have source code in MikroPascal language : http://www.microelemente.ro/MikroPascal ... Source.zip

[kostasgr]

Well the library worked fine for me. I allready communicated with two port expanders without problems.
Special thank's to yo2lio for converting and sharing his sources.