Multiple channel waveform output using a 6711 board

[HeikefromIPP]

Hi,
I am writing a driver for VxWorks RTOS based on the DDK for a NI6711 analog output board.  I cannot find an example for timed waveform output on  more than one channel. I adopted aoex3.cpp (which works fine under VxWorks for one channel) to operate also multiple channels. I set all DACs to timed and wrote to the waveform generation register once for each channel. I tried several settings  for the number of  channels:
    theSTC->AO_Mode_1.writeAO_Multiple_Channels(1);
    theSTC->AO_Output_Control.writeAO_Number_Of_Channels(iNumChans);
None of the settings of  iNumChans results in the correct output  on all selected channels.
The comedi driver uses the settings
   theSTC->AO_Mode_1.writeAO_Multiple_Channels(0);
    theSTC->AO_Output_Control.writeAO_Number_Of_Channels(0); But that does not work either
Any help would be very much appreciated.
Heike

[Jeremy_C]

Section 3.6.1.7 of the DAQ-STC RLP manual (http://www.ni.com/pdf/manuals/340934b.pdf) indicates that you are setting the AO_Multiple_Channels and AO_Number_Of_Channels bitfields correctly for mutliple channels.  On which channels are you wanting to generate signals, and what is the behavior you are seeing?

[HeikefromIPP]

Thanks for your answer Jeremy,
the example attached puts data out on channel 0 and 1. There was a bug in filling the FIFO in he example I attached in my first message. Sorry for that. I attached the corrected one to this  message.  It works fine. I am not sure about the settings of AO_DAC0_Update_Mode and AO_DAC1_Update_Mode. There seems to be no difference when both are set to timed or immediately.

[HeikefromIPP]

Soory , here is the attached example