collecting reading from the port

[Se]

I want to get 20 reading from the port and store each reading in an array of string. Is there anyway of doing that?

[Chris_Rake]

Is this in LabVIEW? If so, the VISA read returns a string, so the work is already done!

[Se]

VISA read returns a string which consists of about 100 readings or more, but what I wanted is just 20 reading or one reading so that I can use those values to manipulate.
for example
(1) A=28 B=81 c=93
(2) A=27 B=83 c=93
(3) A=28 B=83 c=93
(4) A=28 B=84 c=93
(5) A=25 B=83 c=93
(6) A=28 B=87 c=93
(7) A=29 B=83 c=93
(8) A=28 B=83 c=93
(9) A=25 B=89 c=93
(10)A=28 B=83 c=93
(11)A=28 B=83 c=93
(12)A=28 B=89 c=93
(13)A=28 B=83 c=93
(14)A=28 B=83 c=93
(15)A=28 B=83 c=93

They are all in one string buffer reading out off the port. How would I go in getting the first reading (1) or the first five readings (from (1) to (5)?

[Chris_Rake]

I'm assuming you're using VISA under LabVIEW. It sounds like you need to work with the string manipulation vi's. For example, you can use the match pattern vi to search for 'A=' then take the result and search for ' B='. The string remaining would be the number, which you could save in another array.

Check out the string vi's in the string function palette for other functions, including string to number conversion.

[Se]

Is there any way to get the reading from the port to take only 2 or three readings at a specific amount of time? If I'm going to search for e.g. A or B it's gonna be forever and the average of A or B will not be found.

[Chris_Rake]

That depends on the nature of the instrument. If the instrument is always sending data and you just want to sample the last 3 points, you can issue a clear read buffer and then read the next 20 bytes or so and parse that for your data.