X-series analog out fifo preload

Question

i am porting an m-series driver to x-series, and have a quick question about analog output.
i have found that I can preload the aout FIFO by writing sequential data to:
        device.AO.AO_FIFO_Data_Register.writeRegister(val);
however this is a 32-bit register, and through trial and error I have found that i have to write two values at a time:
    for(int i=0;i<preloadCount;i+=2)
        u32 val = buffer[i] & 0xffff;     // buffer has correctly scaled DAC values, as 32-bit ints
        if (i<(preloadCount-1))           // in case preload count not divisible by 2
            val |= buffer[i+1]<<16;
        device.AO.AO_FIFO_Data_Register.writeRegister(val);
is there a way to write one 16-bit value at a time to the analog out fifo?
thanks,
--spg
scott gillespie
applied brain, inc.
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Answer 1

additionally, is there a way to DMA 32-bit values to analog out, without them being interpreted as pairs of 16-bit values?
for analog input, both problems (writes to the fifo, and dma to the fifo) are solved by setting the fifo width:
aiHelper.programFIFOWidth(nAI::kFourByteFifo, status)
but so far I have not found a similar mechanism for analog output.  
national instruments guys, can you comment?
thanks,
--spg
scott gillespie
applied brain, inc.