Xillybus XADC on xillinux

[osmaan_khan]

Hi,

I am trying to interface XADC on Zybo with xillyubus to measure external analog values.Rest of the design is working okay with a counter.My Question is how do i connect XADC with the xillybus Ip Core.

any help is appreciated 

thank you

[vicentiu]

Please contact xillybus for this as we are not familiar with their products.

[osmaan_khan]

They said the same thing. ?

Anyways what is the output pin of the xadc. Which gives out digital values. 

Help me out. Please. 

 

[vicentiu]

It's the Pmod JA port. You can see it in the reference manual

[osmaan_khan]

Thank you for your timely response . 

Now, I want to measure DC voltage.what if I feed in a voltage greater Than 1 volts?

Another question: what is  the purpose of VCC and GND in XADC pmod(the last 4 pins)?

Do their power up the ADC? 

 

Thanks. 

[Ciprian]

HI @osmaan_khan,

To clarify on xillybus and XADC, we have never configured the design which they provide, therefore we don't know how to add the XADC IP to it and interface it with their linux kerne and rootfs.

Regarding the VCC and the GND pins, the PMOD connector JA can be configured as XADC or can be used as a simple PMOD connector (following the PMOD standard you need VCC and GND), when using it in a XADC configuration the VCC and the GND can be ignored.

All the information on how the XADC works, configurations and limitations can be found in ug480 form xilinx. For instance, you cannot measure a voltage grater 1V using the XADC, you will have to scale your voltage in order to measure it with the XADC (maybe use a voltage divider, it depends on you circuit).

The XADC is a Xilinx IP which is configurable both from the IP configuration window in Vivado and trough some registers using the AXI-Lite interface, with a xilinx kernel you should have access to it if the XADC driver is active in the kernel and if the .dts is configured to include the IP. We cannot help you with this, unfortunately; you will have to ask the support team from xillybus about how to manage this.

- Ciprian