Charles, thanks I will give that a go when I get back. I am on the road for the next four days.

One other thing I was thinking about today flying from CO to PA...First off here is what I am doing. I am controlling electric motors on a agriculture planter. Each row has an electric motor. For each four rows I have one control box. In the tractor I have a board and touchscreen. The tractor board can be called the master board. It sends the required motor speed to each board for each rows motor. The planter boards then take the speed, do the PID and then report back to the master the row speed.

The thing I was thinking about was right now I have the master sending out data to each board separately. I was wondering if it would be better if it sent out one data packet that had Control Box ID and the four speeds for every control box within one data stream. So for example I have a 16 row planter. There are four control boxes talking back and forth to the master/tractor board. The master sends out four different packets. Each with Control Box ID and the four row speeds. So all four boards are getting data, only one is doing something with it. The other three are waiting for their data. I am wondering if there would be any drawbacks to send out one packet that would be like this

Box1, Speed1, Speed2, Speed3, Speed4,Box2, Speed5, Speed6, Speed7, Speed8,Box3, Speed9, Speed10, Speed11, Speed12,
Box4, Speed13, Speed14, Speed15, Speed16,

Then the tractor only has to take time to send out one data pack and each control box gets speed data every time the tractor sends out data, no waiting for its own data.

Are there any drawbacks to sending longer data streams?