Two questions about analog outputs

[Russell Hind]

I'm using a 6052E

a) My analog outputs are configured for bi-polar operation which, as I understand it, gives them a range of -10 to +10 V. Why when I call AO_VWrite (nidaq 6.9.3) do I get a status back of 10012 (not -10012 which is bad range error)? Why isn't this value documented anywhere? The value is begin written. I'm guessing it is being reduced slightly to a count of 65535 where as -10 would be 65536.

b) If I have 1 channel generating a waveform, is there anyway to change the voltage on the other channel (not generating a wave form, just one shot output) while the 1st channel is generating a wave form, or do I have to stop both acquisition and generation first? Am I missing something, or is this the case. Currently I
get a -10609 error if I use AO_VWrite while generation is running, even though the channel I am writing two, isn't involved in the generation.

Thank you

Russell Hind

[logman]

Russell,

a) Since 10012 is a positive number, it is a warning which is saying that the function executed successfully, but something wasn't totally right. In this case the specified value was out of range for the channel so the value was clipped to fit within the range. The information for all the errors is found in the NI-DAQ function help.

b) There isn't a way that I can find to just do a 1-shot output on one channel while the other channel is in the middle of a waveform. The only way that I can find is to setup an interleaved buffered output and change the data in the buffer when you want to update the value on the output channel. Here is an EPD which shows how to interleave data for multiple channels: Analog Output Example

[Russell Hind]

a) Thanks. I guessed it was this, but couldn't find anything in the help on 'warnings' (positivate status results).

b) Yes, this is the solution I have already implemented.

Thanks for your help

Russell