IFRIO QUESTIONS

[TurboTurtle]

Hello,

I have the following queries regarding IF RIO. Could you please help me out with the following questions.

1. In the driver example "Stream from Disk.vi" how would I know in 
which mode DAC is working and In case of interpolation mode where i 
have set the I/P data rate?


2. AD9857 takes only real data as input, but in the "Stream from 
Disk.vi" all the data (both I and Q) is given. Why?

3. How would I configure the DAC and DDC directly using the drivers 
with out FPGA?

4. How maximum output frequency 80MHz is achieved in the interpolation mode?

Thanks,

Vishal

Applications Engineer

NI India

[JerryAL]

Hi Vishal

1. I believe for the “driver” example, only the Quadrature mode is supported. The DAC’s DAC Interpolation mode is not supported. Are you sure that you need this mode? The output is AC coupled, with the frequencies below 250 KHz severely attenuated.

2. The AD9857 does take complex data.

3. It is not possible to directly configure the DADCs and DACs while using the driver method of programming. This is not a supported feature of the driver method. The ADCs and DACs can only be configured when programming the module with the FPGA method. And in that case, only with the ADC/DAC features that ni5640R supports. Although, it is possible for you to modify the ni5640R VIs to configure features that are not supported, but you will really have to learn the part spec sheets and learn how the VIs interface to the parts to make the changes.

4. 80 MHz is the front end analog bandwidth. The max instantaneous bandwidth is 20 MHz for the ADC and 40 MHz for the DACs. For example, you can acquire a 20 MHz wide signal BW centered at 70 MHz. (60 MHz to 80 MHz)

Jerry