VISA comport wrong data

[Michael.Koppelgaard]

Having this code getting data from a balance. The code fails every 3 - 4 time.

When things goes well the concated string is : \s1863.57\s\sg\r\n\s1863.57\s\sg\r\n (code display)

When thins goes wrong it could be : p\03\03;\r\n or \03\03;\r\n

What am I doing wrong ?

[crossrulz]

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Michael.Koppelgaard wrote:  What am I doing wrong ?

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You are using the Bytes At Port.  Because you are dealing with a message that includes a termination character, let VISA use that.  So instead of the Bytes At Port, just tell the VISA Read to read more bytes than you ever expect in a message.

[RavensFan]

As Crossrulz pointed out, using Bytes at Port is just wrong.

The reason it fails is that you read the message when you have 6 or more bytes.  But the full message string is 13 characters long when you factor in the decimal point, spaces, "g" and CR and LF.

[Michael.Koppelgaard]

Oh yes you are right. I will try to change. Still have some wrong characters coming

[Michael.Koppelgaard]

No still get weird characters, and I know the parity baud rate etc. is correct

[Norbert_B]

Can you post your current code?

Norbert

[Henrik_Volkers]

It's possible that the scale actually send these characters (or that the communication get disturbed)

so some sort of error checking should be implemented.

Possible checks: min length and last characters a '\sg\r\n'  and a number conversion without warning/error.

If it's of any importance to reliable read the values: Ask the scale manufator if there is a protocol including a checksum!

[Michael.Koppelgaard]

My code now is like this. How do you propose building extra checks ?

I modified the output from balance so the output is the balance data e.g.: 1003.26 or 126.52

[Norbert_B]

You discard all characters when running into the timeout if the last packet is less than 9 bytes. This seems to be wrong as strings will be incomplete.

Norbert

[Michael.Koppelgaard]

Your right. TWill try to change. Might not be before friday. Will return. Thank you all for your help 🙂