1 ratings:

3 out of 5

Rate this Document

Error -200251: "No DMA Channels Available" When Using Multiple Counters

Primary Software: LabVIEW Development Systems>>Professional Development System
Primary Software Version: 7.1
Primary Software Fixed Version: N/A
Secondary Software: N/A
Hardware: Counter/Timers (TIO)>>Devices>>PXI-6602

Problem:
I am doing more than three simultaneous counter input tasks on a NI 6602 or NI 6608, or I am doing more than one simultaneous counter input task on a PCI-6601.

After adding an additional task and running, the following error occurs at DAQmx Start Task.

Error -200251 "Measurements: No DMA channels or USB Bulk Endpoints are available."

How do I resolve this?

Solution:
The PXI-6602 and PXI-6608 have 3 DMA channels and the PCI-6601 has 1 DMA channel. Any additional operations, including counter inputs, must be interrupt based and cannot use DMA.

For instructions on configuring the particular task to use interrupts, see KnowledgeBase 34FGAFVM: How do I Configure the Data Transfer Mechanism (Interrupt or DMA) in DAQmx and Traditional DAQ?.

Related Links:
KnowledgeBase 34FGAFVM: How do I Configure the Data Transfer Mechanism (Interrupt or DMA) in DAQmx and Traditional DAQ?

Attachments:

Report Date: 11/01/2006
Last Updated: 10/05/2007
Document ID: 430FRH7E

Your Feedback!	Poor  |  Excellent							Yes	No
Document Quality?							Answered Your Question?
	1	2	3	4	5
Document needs work? Please tell us why.
Please Contact NI for all product and support inquiries.