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Changing DAQmx range while task is running

And to add even further to Kevin's comments (which is a great tip, gets me around the real short pulses of the sample clock), be careful bumping the convert clock TOO high.


I was measuring some 10-20 mV signals along with some 5-10V signals with mixed gains at the max sample rate of my card (1MS aggregate, or ~30 kHz per channel). The first few mV channels would sampled after sampling the 5-10V signals would come in much higher than they should be due to ghosting on the multiplexed ADC. Basically, there's only one actual ADC in the card and it's scanning through all the channels. If it measures a 7V value, then immediately goes to a 20 mV value, there will be some charge left on the line that needs to dissipate when it drops from 7V to 20 mV. If you're sampling at 1 MS/s then you might wind up sampling quicker than that charge can dissipate, and could read 80 mV or something. At 10 Hz this is not an issue at all, but if you bump the convert clock to 1 MHz then you could still see ghosting.

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