IO Expanders MCP23008

[SneaKSz]

Hi all,

Im facing a stupid problem, I'm able to initialise my I2C IO expander :MCP23008 (https://www.electro-tech-online.com/custompdfs/2011/02/21919d.pdf) .

I'm unable to get an interrupt, but I"m able to set different ports high and low. I cant find the fault.

I want to have an interrupt when an input change from state ( port 7->4). As you can see in the code , Ive set them as input , enabled the interrupts. But the interrupt is always high, and Ive set it as active HIGH , so there is always an interrupt.


Hopefully someone can help me with this problem !

void main(void){

init();// setup
	Delay10KTCYx(300);// wait 333ms startup GPIO
while(1){
	SendByte(0x40,GPIO,0xF0); 
         Delay10TCYx(1);
	SendByte(0x40,IOCON,0b00110010);  // active high
	Delay10TCYx(1);
	SendByte(0x40,IODIR,0xF0); //WriteAddress iodir , high nibble input	
        Delay10TCYx(1);
	SendByte(0x40,INTCON,0xF0); // compare to def val
          Delay10TCYx(1);
	SendByte(0x40,DEFVAL,0xF0);// def val to compare
        Delay10TCYx(1);
	SendByte(0x40,IPOL,0x00); // same pol 	
        Delay10TCYx(1);
	SendByte(0x40,GPPU ,0xFF); 
        Delay10TCYx(1);
	SendByte(0x40,GPINTEN,0xF0); // enable input pin for inter on change	
}
while(1);

!

My I2C pulses are correct !

Hopefully someone can help me !

With kind regards

 

[SneaKSz]

Hi,

I didnt activate the "PEN" via SendStop() , the code works now !

 

[AtomSoft]

Glad to hear you got it working I might buy a couple

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