Write Function on HP4276A does not work

[Oxonium]

Hello,

im using a network analyzer (HP4276A). I want to set frequencies and after that i want to read the data from the displays.

I'am able to read data from dislplay with the VI which is offerd here: https://decibel.ni.com/content/docs/DOC-4094

But unfortunately it is not possible to set frequencies. In the manual (http://cp.literature.agilent.com/litweb/pdf/04276-90000.pdf   page 3-37ff)  you can see that, frequency changes were done by the command e.g. "FR5.0EN" for setting frequencies to 5 Khz. But the HP4276A is not possible to handle with that command.

I set the HP4276A in the adressable mode (see manual 3-26).

I also tried the available drivers wich were available on the NI website for the HP4276A, but they dont work at all. Even reading data are also not possible with that VI (and writing anyway). It says "Instrument specific error".

Im using the NI GPIB-USB-HS.

Hopefully someone can help me.

Warm regards

Oxonium

[Dennis_Knutson]

I don't understand your using that first example at all. Have you tried the simple GPIB Write function?

[Oxonium]

Forgot to say, but yes i also tried the examples. And there is the same problem. I can only read without writing.

I also set a delay, but that doesnt work either.

[Stephan_D]

Hello Oxonium,

as you mentioned in your first post, it is not possible to set frequencies. Do you receive an error message from the example code, that the communication was unsuccessful or another message? How do you know that the frequency is not set?

Regards, Stephan

[Oxonium]

Hello Stephan,

I got no error message from Labview.
The HP4276A has  three displays. Display A & B shows e.g Capacitance and Dissipation. Display C shows the frequency settings. I'am able to read from Display A & B. But as i said before, im not able to change frequencies which i should see on Display C. After i send the command "FR5.0EN" it makes a clicksound coming inside the instrument. But after that the Hp4276A chrashes and i have to push the "self test" button to get the previous state.

Warm regards

Oxonium

[Dennis_Knutson]

Before you do anything else, go into MAX and try to write to the instrument in inter-active mode. Either the GPIB communicator or VISA. See if it works. If it doesn't, perhaps there is something wrong with that very old instrument.

[Oxonium]

I also tried that. Also here i can only read but not write.

[Dennis_Knutson]

Sounds to me that the instrument is broken

[Oxonium]

In the handbook it says after each command there must be a carriage line and linefeed.

So how do i have to write that at the end of the command?

- \r\n

- 1310 (ASCII)

or even

- <CR><LF>

?

I tried all three options but i think the device does not recognize this. I dont know why...

[Dennis_Knutson]

Since you have not shown how you are trying to append the CR and LF, no one has any idea if you are doing it correctly. You have to set the string control/constant for '\' Codes Display in order to use \r and \n. You also have them as constants on the string palette. Your other attempts are not correct.