After searching and reading a few forums posts I understand using sequence is probably not the best idea? I wanted to get some advice on the best way to approach my problem. What I want to do: I plan to use the van der Pauw method and hall effect to experimentally determine various parameters for a small semiconductor sample. At present, it is very time consuming to make all the required BNC connections by hand which in all totals to either 24 or 48 connections to be made. To expedite the process I wanted to make use of Labview to control a micro-controller to control transistors which in turn controls relays that make the required connections. At the same time after each set of required connections are made, a current source controlled by Labview should supply the required current, a volt meter to read the voltage. A total of six different sets of four connections to be made and voltage read for each of the six sets. This needs to be done twice, but since the equipment creating the magnetic field is controlled manually, I can just run the program twice. Recently, I've learned how to control an arduino using labview and also how to control both the current source and volt meter using labview as well. So this is the sequence that labview should send out the commands: Using six digital I/O pins on arduino 1. At start, all pins are set low. 2. First pin set high while rest remain low. This turns on a transistor which makes the first set of connections. 3. Current source is turned on and supplies a specified amount of current to the sample. 4. Volt meter measures the induced voltage and stores that measurement as a double or whatever in something like an array. 5. Current source turns off. 6. Second pin on arduino set high while rest set low and steps 3-5 are repeated until all 6 voltage measurements have been recorded. 7. The 6 measurements should be exported to excel file or notepad or whatever. 8. The same data could be passed to something like a different tab in the same program to perform the calculations to find the semiconductor sample parameters. So now my question on the best way to go about doing these various things. I was looking through labview and found something called a flat sequence, but according to the forums this is supposedly frowned upon. My other thoughts are using some sort of combination of loops/cases, but I'm unsure how to structure it and what should be included/excluded from the loop. Other thoughts are possibly a timed structure. Another possibility is creating 6 different vi and calling them one by one. So basically the program runs and after it finishes, I need each of the 6 voltage measurements, preferably displayed in both a table and saved to excel/notepad.

@SaintsFan wrote: So this is the sequence that labview should send out the commands: Using six digital I/O pins on arduino 1. At start, all pins are set low. 2. First pin set high while rest remain low. This turns on a transistor which makes the first set of connections. 3. Current source is turned on and supplies a specified amount of current to the sample. 4. Volt meter measures the induced voltage and stores that measurement as a double or whatever in something like an array. 5. Current source turns off. 6. Second pin on arduino set high while rest set low and steps 3-5 are repeated until all 6 voltage measurements have been recorded. 7. The 6 measurements should be exported to excel file or notepad or whatever. 8. The same data could be passed to something like a different tab in the same program to perform the calculations to find the semiconductor sample parameters. A state machine with these 8 states (and maybe some helper states: idle, shutdown, startup, error, etc.). 😄 Basically a while loop with a case structure (one case for each state) and a state variable (e.g. enum) in a shift regsiter. Look at the design templates that ship with LabVIEW. (A flat sequence is too rigid for this. What if an error occurs in state #5? The is no way to go to an exception state. What if you want to abort in the middle? What if a state fails and should be repeated.)