AFE7950: two tone generation from DAC

Hi Youngho,

The way of doing this depends on which FPGA board you are using with the AFE7950. Are you using a TSW14J56, TSW14J57 or a TSW14J58? Or a different FPGA?

For the TSW14J56 or TSW14J57 in HSDCpro, in the I/Q Multitone Generator, you can select the number of tones, their bandwidth and their center.

And for the amplitude there is a scaling factor, for -10dBFS the scaling factor = 10^(-10dBFS/20) = 0.3162278.

For the TSW14J58, in latte you can use the following commands:

############# Send Signal to TX AB
amplA=-10
freqA=20
amplB=-10
freqB=-20
AFE.selectCh(2,0) ##Use AFE.selectCh(2,0) for TX AB or change to AFE.selectCh(2,2) for TX CD
AFE.FPGA.sendMultiTone(0,[freqA,freqB],[amplA,amplB],[freqA,freqB],[amplA,amplB])

Where you can set the freqA and freqB as the offsets from the DAC NCO and the amplitude for both as -10dBFS.

Best,

Camilo

Hi Youngho,

Are you using our TI JESD 204C IP in your ZCU102?

To output two tones from the DAC you need to update the design so that you send a two tone waveform from the FPGA to the DAC.

Best,

Camilo

Hi Youngho,

Latte does not have control over the ZCU102, so you would need to update the design you have loaded on the ZCU102.

In the project, there is a file called “sine_64point_att.sv” where a 64-point sine wave is used to send the tone to the AFE. You can replace that sine wave with a 64-point 2 tone waveform.

Best,

Camilo