Modbus Read

[Peter Saraiva]

Hello,

In the Advanced_Serial_Write_and_Read.vi which we can find in the Labview example, in the "read" part of the program, I have to put the right number of byte that I have to read in the buffer and if I don't do it I always have a Timeout error. 

 I want to read the buffer without putting the number of bytes I have to read before. Any idea to fix this problem ?

I enclose the VI.

Thanks

Peter.

[DavidS. · Accepted solution]

Hi,

What you want to do is impossible because the instrument you are controlling needs to know the number of bytes it has to return.

Moreover, the input "bytes to read" is a necessary input.

Normally, when you send an command to your instrument, in the instrument documentation, you have all the information to know the number of bytes to read.

Sincerely