Synchronize buffered pwm outputs on Daqmx

I'm using Daqmx to produce two synchronized pwm outputs.
The pwm outputs:
a) have variable controllable frequecy, and therefore use buffered data as input to daqmx write vi. and also use 'implicit' as input to clock type in timing vi
b) have their beginning edges synchronized
The design I use uses two separate tasks to create the signals. The only way I could think of of synchronizing the pulses was by putting the 'start vi' and 'write vi' in two different sequential frames. The idea doesn't seem to work, the two pulses somehow drift apart on the oscilloscope. Even the start part does not work; there seems to be a delay.
Since I'm not using any clock to generate the signals (implicit), how can the two pulses be synchronized?

Hello lvuser111
You may take a look to this community example, it could give you a good idea how it may be implemented:
Synchronize Two Counter Output Tasks Using a Dummy AI Task
Regards
Mart G

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Hi,
You have a couple of options. You can set your timing to N
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Attachments:
TestAll-NI.vi ‏32 KB

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Hi guys, ive encounter some problem in myrio 1900, which is using PIN31 for digital output and PWM output. while the testing , i cant sending PWM, i only can passing the read value from other Digital input and transfer towards PIN 31. ive tried to change in low level logic but myrio disconnect after 3-5 seconds. By the way ive attached few picture to clarify my current situation, hope can clarify my problem clearly.
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Attachments:
1.png ‏51 KB
2.png ‏49 KB
3.png ‏49 KB

http://forums.ni.com/t5/Academic-Hardware-Products-ELVIS/bd-p/10

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Attachments:
SkipColor1.vi ‏111 KB
MotorControl2.vi ‏99 KB
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Hey suspencefull,
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Attachments:
myRIO-1900 Customized FPGA.vi ‏388 KB
RT Main.vi ‏506 KB

Synchronize buffered pwm outputs on Daqmx

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