Hello
I am trying to request a 50Hz sample rate in TC mode in NI9219 and meanwhile a 100kHz per channel AI sample rate in NI9205 for 2 channels. Two acquisition start simultaneously and run under constant phase delay(synchronization under different sample rate? I don't know if I descripe it in the right way). I have tried 2 methods.
First, I set a single Task for these 2 types of measurment and the sample clock is 100kHz. AI Voltage for 9205 and AI Temp for 9219 are routed by the
same task. As shown in Attach1. The default ADC Timing Mode is set to High Resolution(2Hz) for thermocouple measurements in 9219. To change it to High Speed(50Hz), DAQmx Channel Property Node is inserted as instructed by
http://digital.ni.com/public.nsf/allkb/1015F4182FB8A805862572D1006B4CC1
Here the problem comes probably because the AI Voltage for 9205 in the same task.
Second, I tried to use different AI Timing Engines(ai/SampleClock and te0/SampleClock ) in cDAQ-9174 to sample NI9205(100kHz) and NI9219(50Hz) at differnet frequency, as shown in attach2. Although cDAQ has 3 AI Timing Engines, when I source ai/SampleClock to the DAQmx Timing(Sample Clock).vi, it seems not working.
Thank you for all your help.
Same content has been sent by email by mistake. Sorry.
attah1,2.vi are in the attachment.
Regards
Bing@NCL
