UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

cancel
Showing results for 
Search instead for 
Did you mean: 
Visitor pedro4
Visitor
2,250 Views
Registered: ‎07-14-2017

XADC not converting?

Hello! When using XADC + Xillybus, I open Hardware Manager in Vivado just to monitor the XADC. Temperature is always -273.1ºC and volts in VAUX0, VAUX8 and VP/VN is always 0.00. When I run this tutorial I use the Hardware Manager again to monitor and everything seems fine, temperature is at 30ºC and volts in VAUX0 looks great (even change when I put my finger on the pins, as expected). So I am starting there must be something wrong with the combo XADC + Xillybus or maybe I'm not accesing the XADC properly? Although the XADC seems to convert, but it looks like it's always converting the same thing (although values change a little, implying is not stuck in the same result forever) and I'm always getting values like 0080, 0081, 007F and so.

 

Do you have any clue on what might be causing this? I'm currently connecting the EOC signal of the XADC to the DEN of the XADC to output values and the CHANNEL signal to the DADDR ("00" & CHANNEL, since CHANNEL is only 5 bits and DADDR is 7 bits wide) as proposed in the XADC doc.

 

Do you have any clue on what might be causing this? thanks!

0 Kudos
5 Replies
Scholar hbucher
Scholar
2,222 Views
Registered: ‎03-22-2016

Re: XADC not converting?

@pedro4  Well -273.1C is zero Kelvin. So pretty much everything is zero.

I would add some ILAs and check the bus 

It seems to me too many moving parts at this point

vitorian.com --- We do this for fun. Always give kudos. Accept as solution if your question was answered.
I will not answer to personal messages - use the forums instead.
0 Kudos
Visitor pedro4
Visitor
2,211 Views
Registered: ‎07-14-2017

Re: XADC not converting?

@hbucher I tried doing what you mentioned, and I probed EOC, DRDY and CHANNEL[4:0] from XADC and:

 

  • set a trigger for EOC when it was == 1.
  • set a trigger for DRDY when it was == 1.
  • set a trigger for CHANNEL[4:0] when it was > 00000.

None of them triggered tho, but I think that might be cause I don't know hot to use ILA properly, never used it before.

 

But I tried printing which channel the XADC was converting and it's always channel 9 (that is ADC A offset). I don't really understand what's going on.

 

0 Kudos
Visitor pedro4
Visitor
2,134 Views
Registered: ‎07-14-2017

Re: XADC not converting?

Sorry for the double post, but I can't see an "Edit" button anywhere.

 

So I've been doing some tests. I started a new fresh project where I only instantiated an XADC (I used the wizard and set it up exactly as the one I have set up in my Xillybus project). Left all the outputs open and just fed it with a 100 MHz clock. Generated the bitstream, programmed the FPGA and using the Hardware manager in Vivado, I monitored the XADC and it worked perfectly! Then I just copied it to my Xillybus project and I created an VHDL where I didn't connect the XADC to anything other than the clk_100 (the 100 MHz clock signal) from Xillybus. I didn't even connect it to the FIFOs, it was just there sitting with Xillybus but with no connection to it, just like in my test project from before. And then I opened the Hardware Manager to monitor the XADC and then again, -273.1ºC and 0.00 V in all channels... I'm starting to think Xillybus is messing with the XADC some way I'm not aware of.

0 Kudos
Scholar hbucher
Scholar
2,129 Views
Registered: ‎03-22-2016

Re: XADC not converting?

@pedro4 It is possible.  I am not familiar.

Have you filed a support request with them? It is a paid product.

vitorian.com --- We do this for fun. Always give kudos. Accept as solution if your question was answered.
I will not answer to personal messages - use the forums instead.
0 Kudos
Visitor pedro4
Visitor
2,126 Views
Registered: ‎07-14-2017

Re: XADC not converting?

@hbucher I hadn't but I will do that soon. I'll send them an email and see if they can help me. As for now, I'll try using Xillybus Lite and see if that works. Anyway, if someone knows about this I'll be more than looking forward to hearing about it. Thanks for your your time hbucher.