Continuous buffer with interrupts doesn't refill the buffer

[grivlis]

remember that the counter can hold 256 elements. I am showing you the first 8 items and last 8 items in each buffer. That means that the difference between the 1st and last item (after the buffer fills only once) is about 255*1000, which is exactly what you see.

Gil

[grivlis]

Hi Kenn,

Any ideas on the problem?

Thanks,
Gil

[Kenn_N]

Gil,

Thanks for following up.  We have been doing some testing with the labview driver to be sure it works there and it does.  We are still doing some verification of the problem with the C code.  I will post with any updates.  Thanks for supplying this feedback.

Regards,

[Kenn_N]

Gil,

We do have a request.  We'd like to narrow this down to the 6602.  Can you take the 6533 out of the scenario and provide an external signal and see if the issue remains?  Thanks.

Regards,

[grivlis]

I'll see what I can do. Do you want a completely external signal (as in a function generator) or can I use another 6602 for pulse trains?

Gil

[Kenn_N]

Gil,

Completly external, although if it happens with it's own pulse train, that would be interesting as well.  Thanks

Regards,

[grivlis]

Ok. Attached (in the zip file) are t5.exe and its source code t5.cpp. This executable displays the same behaviour, but uses external gate (about 100 Hz) and internal source connected to the internal 100kHz. The output looks like this:

counter buffers before acquisiton:
counter 0 buffer begining: 0, 0, 0, 0, 0, 0, 0, 0, ...
counter 0 buffer      end: ..., 0, 0, 0, 0, 0, 0, 0, 0
counter 1 buffer begining: 0, 0, 0, 0, 0, 0, 0, 0, ...
counter 1 buffer      end: ..., 0, 0, 0, 0, 0, 0, 0, 0


counter buffers after 3000 ms acquisiton:
counter 0 buffer begining: 257532, 258537, 259541, 260545, 261550, 262554, 263559, 264563, ...
counter 0 buffer      end: ..., 249498, 250502, 251507, 252511, 253515, 254520, 255524, 256528
counter 1 buffer begining: 616, 1620, 2624, 3628, 4633, 5637, 6641, 7645, ...
counter 1 buffer      end: ..., 249494, 250498, 251503, 252507, 253511, 254516, 255520, 256524

Gil

[Kenn_N]

Gil,

Thanks for this.  I will try this out this afternoon.  Could you post the code for this?  Thanks.  And I assume that the 6602 is device 1?  Thanks again.

Regards,

[grivlis]

the code is attached in the zip file.

Gil

[grivlis]

And here is a zip file with t6.exe and t6.cpp. In this executable (which displays the same behaviour) I use a 100Hz pulse train generated by channel 7.

counter buffers before acquisiton:
counter 0 buffer begining: 0, 0, 0, 0, 0, 0, 0, 0, ...
counter 0 buffer      end: ..., 0, 0, 0, 0, 0, 0, 0, 0
counter 1 buffer begining: 0, 0, 0, 0, 0, 0, 0, 0, ...
counter 1 buffer      end: ..., 0, 0, 0, 0, 0, 0, 0, 0


counter buffers after 3000 ms acquisiton:
counter 0 buffer begining: 256946, 257946, 258946, 259946, 260946, 261946, 262946, 263946, ...
counter 0 buffer      end: ..., 248946, 249946, 250946, 251946, 252946, 253946, 254946, 255946
counter 1 buffer begining: 943, 1943, 2943, 3943, 4943, 5943, 6943, 7943, ...
counter 1 buffer      end: ..., 248943, 249943, 250943, 251943, 252943, 253943, 254943, 255943