Multiple gpio with function

[stinggray]

I have a newbe question.

I'm setting up a dashboard to monitor liquid in tanks. I will use 4 sensors to a digital pin on an Arduino then to rpi. In node-red after receiving the gpio If it's high I change it to .20, so I ether a 0(low) or .20(high) from each gpio after the changes. Here is where I stuck. How do I add the 4 gpio in the function node and get a total msg.payload?

[Colin]

Have a look at this post from the cookbook for how to combine data from different streams

[stinggray]

I looked at the join and that's not what I need to do with the data. Here is a scenario I'm trying to do. Lets say two of the sensors on the tank are high and each one has been changed to .2 I need to add (.4 = .2 + .2) and enter the .4 into a dashboard gauge. I'm just sure how this done in the function node.

[Colin]

Did using the join node solve the first part of the problem, which is to get both values in one message?

Edit: Once you have both the numbers available then the rest is easy.