Using Two Buffered Position Counters Causes Error

[rclarkii]

I'm trying to synch two counters on a 6601 counter
card in Buffered Position Mode to a 6023 DAQ card
using RTSI. I've gotten a single channel to work OK
but when I duplicate the init code for the second
channel using another group, I get the error -10455
(Counter Control Error - No DMA Channel Available
For Use) when setting PROGRAM control mode. Can I
buffer more than one channel at a time??

[JustinBritten]

If you examine the User Manual for your 6023 board, or refer to the KnowledgeBase article linked below, you will find that your board has only 1 DMA channel. Each buffered operation requires the use of one DMA channel. Therefore, with your hardware, you are only able to program one buffered operation. The other operations must use interrupts to perform the data transfer.

How Many DMA Channels Does My E Series Data Acquisition (DAQ) Device Have?
http://digital.ni.com/public.nsf/websearch/E00C0F790CA2CDA686256BF000614DE1?OpenDocument

Also in this KnowledgeBase you will find that we have multiple boards which have up to 3 DMA channels.

Regards,
Justin Britten

Applications Engineer
National Instruments

[rclarkii]

Actually I don't think it is the 6023E that
is the problem - it is the 6601 that is the
problem. I found the 6601 only has 1 dma
channel and the 6602 has 3. I intend to
replace the 6601 w/ a 6602.

Rob Clark

[JustinBritten]

Rob,

Yep ... correct. Buffered Position Mode would be the application on the counter board. Therefore, the 6601 is the problem. As you mentioned, the 6602 would solve this issue.

Regards,
Justin Britten