Main Site Documentation

Relay x16 Board


Can I have multiple Relay x16 Boards on the same Cobra? I think I read they can be daisy chained but I cannot find anything on that.


Yes they use I2C so they can be chained, up to 7 (112 relays!)

You need more than 16 relays?! Must be some cool project :slight_smile:


homemade beer system!


How do I chain them? Any pictures or docs around?


You need to manually create “Y” cable. It is a simple pin to pin connection. Remember to change the address on the device using jumpers.


Figured that out. But any recommendation on talking to the 2 boards at the same time? Seems only one I2C device can be active at the same time:

var I2C = new I2CDevice(new I2CDevice.Configuration(0x20, 100));
var I2C2 = new I2CDevice(new I2CDevice.Configuration(0x21, 100));

It fails when it trys to open i2c2…


Correct. Read the wiki page on how to use multiple I2C devices




I changed the driver to support 8 boards. Interested in it?


yes sure


I attached it. Works great for me. I like the function GetRelayFromNum but it does add lots of extra lines.



I’d sure like to see this code. Can someone forward it to me? Also I don’t see any dips on my board



Can someone post the code to address multiple relay boards? I’m too lazy to figure it out myself :wink: