03-06-2006 12:57 PM
03-07-2006 02:38 PM
The Low-Cost M Series devices offers 16 bits of resolution and an analog output range of +/-10 V, giving you a code width of about 0.3 mV. The absolute accuracy is 3.23 microVolts. You can see this information for yourself in the M Series Help (User Manual and Specifications). I was looking at the specifications for the PCI-6221. Our lowest cost options, USB-6008 or 6009, will not work for you because they do not have the ability to do hardware-timed analog output.
Please let me know if you have any questions about this.
03-07-2006 02:48 PM
03-07-2006 05:37 PM
This does seem correct. The DAQPad 6015/6016 specifications say that software timed analog output can go to 300 S/s (system dependent) and hardware timed analog output can go to 50 S/s (system dependent). You will be much better off with a PCI device for analog output because of the much higher rates.
03-07-2006 07:26 PM
03-09-2006 08:48 AM
03-10-2006 11:27 AM
Are you using the DAQmx Test Panels? The frequency of the wave you produce should be 1/1000th of the update rate you specify and it should show in the Frequency indicator. So with a 1000 Hz update rate, you should get a 1 Hz sine wave. The specifications for the analog output of this device are:
|Max update rate|
|DMA 3||10 kHz, system dependent|
|Interrupts||1 kHz, system dependent|
03-13-2006 01:39 PM
03-13-2006 02:24 PM
03-13-2006 02:35 PM
I haven't even written any code yet. I'm just trying the examples first. One I am trying out is the Cont Gen Voltage Wfm-Int Clk.vi
I'm using the PCI-6025E card. When I load the example, it is already set for 1 kHz, Sinewave, 250 samples per buffer, 1.00 amplitude, and 5 cycles per buffer. With these settings, it gives an error right off (Onboard device memory underflow). I can play with the numbers...changing the samples per buffer to 2500 and cycles per buffer to 100. I get a 1 kHz signal, but it is "stair stepped" and can never really get a clean 1 kHz signal.