data in host vi not displaying in fixed point format

[gemma1212]

Hi,

The DMA FIFOs are configured as fixed point with integer length 16 and word length 19. Data when acquired by DMA FIFO in FPGA is showing both integer and mantissa. But when acquired in Host its only showing the integer and I am losing mantissa. Does it get rounded up? Is there a way I could get the exact data both mantissa and integer?

Ta

[PauloM]

Hi,

Can you post your code?

I don't see it happening here.

[gemma1212]

Hi ,

Please find the code snippets attached for host and fpga.

Ta

[PauloM · Accepted solution]

Hi,

The fixed point array in your host vi is defined as: 33 bit word length and 33 bit integer length, this way you will never have non integer values.

You have to change your fixed point configuration. Right click the array, select properties and change the settings in the data type tab of just select adapt to source.

Hope this helps,

Paulo

[gemma1212]

THanks a million Paulo.
I found adapt to source but it wasn't under properties. And I couldn't find that it was 33 bit word. In my properties there's no option as data type. I am using Labview 2009. Do you have different version?

You have given me the solution though, my vi is updating fixed points now. While we are on this, can I ask what is the best way to ensure that I get all the points c module is acquiring. My c series module is sampling at 500 kS/s. However, my highest frequency signal is 10kHz, is the loop rate of 4000 ticks is the answer?

Ta