I2C slave triggering

[Deepak J]

Hi ,
Is there some way in which a slave device (an arduino in my case) send a data without a master(raspberry pi) requesting it..? Like what we do via a serial communication...? Something like a slave triggering the communication..

Both general answers and arduino specific answers would be of great help. .

-Thanks in advance

[joan]

I don't think there's anything in the I2C standard which provides for a slave triggering a transaction. It sounds a bit like an SMBus Alert.

Why not implement your own? Send a signal on a spare Pi gpio to tell the Pi you want servicing.

[Deepak J]

Send a signal on a spare Pi gpio to tell the Pi you want servicing.

The problem is, I don't have a spare GPIO on the pi..all the ports (even the spare headers has been used)...

[joan]

Send a signal on a spare Pi gpio to tell the Pi you want servicing.

The problem is, I don't have a spare GPIO on the pi..all the ports (even the spare headers has been used)...

Then you'll need to get the Pi to poll the Arduino for I2C messages at regular intervals.

[Deepak J]

ohkk..den...thanx for the reply....my arduino is failry busy always...but still i'll try doing that ...

[Richard-TX]

Send a signal on a spare Pi gpio to tell the Pi you want servicing.

The problem is, I don't have a spare GPIO on the pi..all the ports (even the spare headers has been used)...

I think it may be time to rethink what you are doing. If you have multiple I2C devices and are monitoring the INT from each, then I would at least consider configuring each device to use Open Drain and tie all the interrupts together and use a single GPIO pin..