DAC38RF86: JESD SYNC error (red light) on DAC38RF86EVM

Vaibhav,

Those LED's are unused and turn on by default after power is applied to the DAC EVM. Are you having an issue with your setup? If so, what mode are you using?

Regards,

Jim

Thanks, thats good to know. I am trying to setup in the on board VCXO clock mode (CMODE4 in the documentation). I am actually trying to use DAC as a signal generator where it generates  100 MHz sinusoidal pulse and uses onboard VCXO clock ( no external clock provided). However, as the CMode 4 settings are not clearly mentioned in the documentation, it is proving a bit difficult to get the DAC to setup that way. Is it possible to catalog the hardware/ software modifications to the DAC for generating100 MHz sinusoidal pulses in Single DAC mode? Thanks a lot for your help.

Vaibhav,

Follow the attached instructions to allow to you produce a 100MHz output tone with no external clock used by the EVM.

Regards,

Jim

DAC38RF82EVM_OnboardClocking_2949.12M_NCO_100M.pptxLMK_2949.12_NCO_100M.cfg

Hi Jim,

Thanks for the instructions and the config file, it works brilliantly and I am able to get an output tone of 100 MHz ( can even tune it for higher frequencies using NCO frequency box). Just had some queries regarding the output and how to generate custom patterns:

1) For this mode, I did not even have to configure DAC or Reset DAC JESD Core and SYSREF TRIGGER, is it because those options are for external clock/on PLL clock mode and do not play a role when generating using on- board VCXO mode.

2) Also, as I am trying to increase the NCO frequency the noise on the output tone is increasing, is there a way to decrease the noise?

3) Thirdly, my final goal is to generate wideband signals which are in a .csv format. ( to load .csv file in the HSDC Pro and sending it to the DAC). Is it possible to send custom patterns using this mode, and how would one go about it? Is it possible to catalog the hardware/software modifications for generating this pattern? I am attaching the .csv file and its screenshot in the HSDC Pro software for reference.

I and Q signals RRC filter.csv

Thanks a lot for your help with such comprehensive queries. Looking forward to your response.

Thanks and Regards,

Vaibhav Jain.

Vaibhah,

1. The configuration file I sent programmed both the LMK and DAC to allow for this output. JESD data was not used so the JESD reset and sysref trigger are not required.

2) Also, as I am trying to increase the NCO frequency the noise on the output tone is increasing, is there a way to decrease the noise? Use a higher frequency DAC clock. This can be accomplished by using the DAC internal PLL or provide a higher frequency external clock that feeds the DAC directly.   

3) Thirdly, my final goal is to generate wideband signals which are in a .csv format. ( to load .csv file in the HSDC Pro and sending it to the DAC). Is it possible to send custom patterns using this mode, and how would one go about it? Is it possible to catalog the hardware/software modifications for generating this pattern? I am attaching the .csv file and its screenshot in the HSDC Pro software for reference.

You can load custom .csv files to HSDC Pro. TI offers software that will allow you to create certain types of test patterns. See attached for more info.

Regards,

Jim

slwu082.pdfHSDC Pro user guide - latest version.pdf

Hi Jim, 

Thanks for the quick reply and resolving my queries. Regarding the third query, I am able to load the wideband signal in the HSDC Pro using the .csv created (.csv attached ), but I am unable to send it on the DAC and get the signal out of the DAC. The steps I am following are:

1) In the DACRF86EVM GUI Toggle DAC Reset B pin, loading default, configuring DAC with the settings shown in the screenshot (Fig 1), resetting JESD Core and Trigger SYSREF in the DAC GUI

2) Loading the .csv file (file attached) for the wideband signals in the HSDC Pro and setting DAC Data rate as 368.64M and clicking Send Button. (Fig 2)

3) After this, I am clicking the Reset the JESD Core and Trigger SYSREF in the DACRF86EVM.

With the hardware settings for VCXO mode, I am following above steps to generate the wideband signal, however I am unable to do so using these steps. What other additional steps/ modifications I need to perform such that I will be able to generate this pattern through the DAC into the oscilloscope.

Thanks for the help. Looking forward to your response.

4274.I and Q signals RRC filter.csvDAC38RF86EVM config.cfg

DAC38RF82EVM_OnboardClocking_2949.12M.pptxVaibhav,

Please follow the attached instructions.

Regards,

Jim

Hi Jim, 

Thanks so much for the quick reply. I followed the instruction in the ppt and gave it try multiple times, but its still not working. I am attaching the config file after doing all the changes, so you can have a look into the config file to check if I have made all the changes suggested. Am I missing any simple configuration here? And, actually the NCO file still works very well, the issue is just when using it to send custom patterns using JESD.

Thanks again for the help. Hopefully next set of changes would make it work . Thanks for the continued help.

DACRF86EVM_modified_config.cfg

Thanks and Regards,

Vaibhav Jain.

Vaibhav,

You did something wrong as your confg file is not matching mine. Try using the attached config file after doing a reset and loading the default values. Please use the multitone generator to verify you can get a valid tone out. Create a 100MHz complex tone with this tool then send it. Go back to the DAC GUI and do  JESD Core reset. You should see a valid output.

I also think there is something wrong with your test file as I only get bad data out when I try to use it.

Regards,

Jim

821_Fs_29490.12_LMK.cfg