Basys3:xadcdemo question

[jmh]

I've implemented the Basys3 xdcdemo project. On the webpage https://reference.digilentinc.com/basys3:xadcdemo it says "For this demo, the AD6, 7, 14 and 15 pins are used on the JXADC header, I thought the pins were numbered 1 through 12. 

How am I supposed to connect the voltage I'm measuring? Also, how much volts can I input safely?

 

Thanks very much,

John

[jmh]

I see, according to the page cited above,  https://reference.digilentinc.com/basys3:xadcdemo,  that in order to build and program the xdcdemo ...

"You will need…

1. Vivado installed on your computer
2. Nexys4-DDR board from digilent
3. Wires and a voltage to measure"

So, it seems, the project was originally targeted to the Nexys4. Perhaps that's why it references pins AD6, 7, 14 and 15 on the JXADC header. 

The Basys3 Reference Manual at https://www.digilentinc.com/Data/Products/BASYS3/Basys3_rm.pdf shows clearly that you are correct, hamster, and the inputs are pins 1, 2, 3 and 4.

I was going to attach a picture of my circuit and schematic but when I try I am warned that I am "only allowed to upload 501.76kb." although my picture is only 24k

[Alex]

Hi John, I think the input voltage should be less than Vcc. You can take a look at the reference manual and find out the Vcc. 

You can use any power supplies / function generator to generate the input voltage. 

[hamster]

That corresponds to the JXADC PMOD pins 1, 2, 3 and 4. 

Pages 1 &  6 of the schematics (http://www.digilentinc.com/Data/Products/BASYS3/basys_3_sch_public.pdf) have all the information you need to verify this four yourself. The XADC is on Bank 35 (centre of page 6), the ADC input filtering is the top/right of page 6 and then wring to the PMOD connector is in the top left of page 1.

[JColvin]

If you need to, you can upload larger images to our Gallery instead.