Error outputting square wave

I am using a USB-6259 unit to control a heater relay. I'm using a square waveform generator to generate an analog waveform and then converting it to a digital waveform. The waveform graph looks like it's supposed to when I do not try to output it to the digital output, but I get error 200547 when I try to send the waveform to the digital output. This error says that DAQmx Write failed because a previous DAQmx Write automatically configured the output buffer size. I did both things the error message suggested I try, which were to set the AutoStart to true (resulted in having not enough data in the buffer) and calling DAQmx Configure Output Buffer (said it wasn't applicable to this task.) How can I get the digital waveform to write to my output channel? I've attached the code below. Thank you.
Attachments:
Heater.vi ‏414 KB

I followed your suggestion and I am still getting Error 200547. No changes I made to the output task helped. I have attached my new code. Do you have any other suggestions?
Attachments:
Heater_3.vi ‏301 KB
TC_TypeK.vi ‏43 KB

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Attachments:
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Hi ALAN,
Thanks for your reply, well the square appears to be overlapped ie one ON/OFF period another waveform tries to overlap, actually i planned to take a snapshot of my oscilloscope (tetronix) but since its not advanced one ,i have attached the file kindly look into it,you can observe the at some higher frequencies there is lot of difference between rise time and fall time.
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alan actually iam decorating my front pannel do u have any sample layouts for coloring ,buttons kindy forward me .
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"st" wrote:
> answer me at my mail
give a valid e-mail first, and your name, we don't like to help anonymous
people
> try to send me example.
how much do you pay ?
> i have transefer function like (1/(s^2+s+5)) and i have a square wave
> input , i want to use this transfer function with this input to see
> the output , how can i do that
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Sorry about duplicate post. My internet connection is very slow today.
Message Edited by johnsold on 05-31-2010 12:05 PM

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Error outputting square wave

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