error 201025 & error 200802 on USB6229 DAQ

[tsunami]

I am attempting to read in a quadrature encoder signal, process the data & resend the processed info back out of the USB-6229 DAQ board.  I keep encountering either error 201025 or error 200802 depending if I set the autostart option of the DAQ write to T or F.  As an experiment I successfully constructed a simple DAQ read & write loop that reads in a square wave from a signal generator.  The simple VI works GREAT but when I apply the same strategy to my VI reading an encoder signal I cannot avoid the 2 error messages listed above.  I AM LOST.  ANY SUGGESTIONS?  I have attached a pdf that shows my VI's + I included both VI's.  The 1st VI in the PDF is the one that works well & the 2nd is the problem child.  The dialog of the 2 errors are included below:
 

Error -200802 occurred at DAQmx Write (Analog Wfm 1Chan NSamp).vi:6

 

Possible reason(s):

 

Measurements: Write cannot be performed when the task is not started, the auto start input to DAQmx Write is false, the Sample Timing Type is something other than On Demand, and the output buffer size is zero.

 

Call DAQmx Start before DAQmx Write, set auto start to true, modify the Sample Timing Type, or change the output buffer size.

 

Error -201025 occurred at DAQmx Write (Analog Wfm 1Chan NSamp).vi:6

 

Measurements: Non-buffered hardware-timed operations are not supported for this device and Channel Type.

 

Set the Buffer Size to greater than 0, do not configure Sample Clock timing, or set Sample Timing Type to On Demand.

 

 

[tsunami]

I thought I did attach my VI's.  I'll repost them & the VI that works is the Read2Write.vi & the one that causes the errors is PIDoutputb.vi.  I attempted to execute the WRITE task in the same fashion as in the Read2Write.vi to no avail.  I have attempted to switch the order of the START task & I still encounter problems.

Read2write1.vi:
http://forums.ni.com/attachments/ni/250/41952/1/Read2write1.vi

PID outputb1.vi:
http://forums.ni.com/attachments/ni/250/41952/2/PID outputb1.vi

[tsunami]

I successfully navigated around error 201025 by your suggestion to be sure data is available for the WRITE task by creating a constant input for the 1st WRITE outside the loop.  Now I am inside the WHILE loop & encountering other errors.  So I obtained from the EXAMPLE Finder the vi's "Meas Angular Position-Buffered-Cont-Ext Clk.vi" & "Cont Gen Voltage Wfrm-Int Clk-Non Regeneration.vi".  I can set the clock for both vi's as the AO sample clock & the 2 vi's can be run simultaneously.  However, in an attempt to merge the 2 vi's into a single loop the timing of the READ & WRITE tasks while on the same source do present some conflicts that generate errors 200016 & 200284.  It appears 200284 terminates the WRITE task & then the READ eventually times out because the AO sample clock gets terminated when the WRITE task to go in error.
 
I attached the merged vi.  Any suggestions on coordinating the timing in this vi I believe will render a viable solution for the PID output.vi (I HOPE & welcome suggestions)

mix & match.vi:
http://forums.ni.com/attachments/ni/250/41982/1/mix & match.vi

[RT4CY]

I'm not sure why you are not able to download the VIs, what browser and browser version are you using?&nbsp; I am using the newest <a href="http://www.microsoft.com/windows/products/winfamily/ie/default.mspx" target="_blank">Internet Explorer</a>.&nbsp; I've attached the VI below.&nbsp; By the way, this example program synchronizes an analog input and a counter input task.&nbsp; If you would like an example that synchronizes an input and output task, please take a look at the Multi-Function-Synch-AI-AO.vi example.&nbsp; Open up LabVIEW, and go to Help»Find Examples.&nbsp; Then browse to&nbsp;Hardware Input and Output»DAQmx»Synchronization»Multi Function.&nbsp; Here you can find several useful examples which deal with synchronizing multiple functions, as well as teh example that I mentioned.

Count Digital Events-Buffered-Continuous-Analog Clk.vi:
http://forums.ni.com/attachments/ni/250/42042/1/Count Digital Events-Buffered-Continuous-Analog Clk.vi