fail to load pattern to Agilent 81134A

[KKNG]

Hi,

I failed to load the "CJTPAT" pattern to the Agilent 81134A, the pattern source is from Agilent pattern loader, with the "ag8113x Write Data Pattern From File Example.vi". I found that the data length shown in the instrument is only 32b, which is the default value of the VI, while the pattern data length shall be 2640b. However, the VI can load some other patterns, e.g.CRPAT and PRBS, and it matchs the data length. During the debugging, I found that the data length and the binary pattern generated by the VI are correct, but it just doesn't work as expected. Can somebody tell me what's going on?

Agilent pattern loader: http://www.home.agilent.com/agilent/redirector.jspx?action=ref&cname=AGILENT_EDITORIAL&ckey=1413519&lc=eng&cc=US&nfr=-11143.0.00

 Best Regards,

[Dan_K]

Hello KKNG,

Could you provide a little more information.  You mentioned that the data length and the binary pattern are correct, in what way does it not work as expected.  Also, have you tried using the National Instruments driver for this device:

Instrument Driver: Agilent Technologies 81134A

Any additional information you can give would be very helpful in diagnosing this problem.

[KKNG]

Dan,

Yes, I'm using the NI 81134A driver as mentioned. The VI example attached in my 1st message is extracted from it. Now, I'm using the Agilent pattern loader to load the CJTPAT pattern to the 81134A via GPIB. The data length and pattern shown in the 81134A matchs the specification. However, it just doesn't work with the NI driver example. The data length shown in the 81134A is only 32b, but it work fine with CJPAT pattern.  So, I need some advice to solve this problem.

Regards,

KK

[Dan_K]

Hello KK,

I'm still not sure exactly what the issue is.  I have extracted the pattern from the Agilent pattern files and found that the CJTPAT has a size of 2640 bytes.  Where do you see the data length as only 32 bytes?  Is it on the front panel display of the 81134A?  Have you tried other patterns of similar size?  Is this problem exclusive to the CJTPAT pattern?

[KKNG]

Dan,

Yes, the data length displayed in the front pattern is 32b only when I load the CJTPAT, while CRPAT is 3350b. The VI works fine on CRPAT and some PRBS patterns. In fact, this VI has 2 parts, read data pattern from file and write data patten. So, I tried to debug this VI and I found that the 'read data pattern from file' read the correct pattern and got the correct data length. However, it just failed to download correctly to the 81134A

Regards,

KK

[Dan_K]

Hello KK,

Have you tried using the ag8113x Error Query VI to find out if your device is throwing any errors in this operation?  Is there any other behavior that is unusual when you try to write the CJTPAT pattern?