====== Arty A7 XADC Demo ======
{{:reference:programmable-logic:arty-a7:demos:arty_xadc1.jpg?400|}}
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===== Description =====
This simple XADC Demo project demonstrates a simple usage of ARTY A7's XADC pin capability. The behavior is as follows:
* The 8 User LEDs increment from top right to left then bottom left to right as the voltage difference on the selected XADC pins gets larger.
* The four switches select which channel to read from.
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===== Inventory =====
* Arty A7 with a MicroUSB Programming Cable
* Vivado installation compatible with the latest release of this demo (2022.1)
* //See [[programmable-logic:guides:installing-vivado-and-vitis|Installing Vivado, Vitis, and Digilent Board Files]] for installation instructions.//
* Wires and a circuit to measure
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===== Download and Usage Instructions =====
First and foremost, releases - consisting of a set of files for download - are only compatible with a specific version of the Xilinx tools, as specified in the name of the release (referred to as a //release tag//). In addition, releases are only compatible with the specified variant of the board. For example, a release tagged "20/DMA/2020.1" for the Zybo Z7 is only to be used with the -20 variant of the board and Vivado 2020.1.
The latest release version for this demo is highlighted in green.
**Note:** //Releases for FPGA demos from before 2020.1 used a different git structure, and used a different release tag naming scheme.//
^ Board Variant ^ Release Tag ^ Release Downloads ^ Setup Instructions ^
| Arty A7-35 | @#C0EEBD: 35/XADC/2022.1-1 | {{https://github.com/Digilent/Arty-A7/releases/download/35/XADC/2022.1-1/Arty-A7-35-XADC-hw.xpr.zip|Arty-A7-35-Pmod-VGA-hw.xpr.zip}} | See //Using the Latest Release//, below |
| Arty A7-100 | @#C0EEBD: 100/XADC/2022.1-2 | {{https://github.com/Digilent/Arty-A7/releases/download/100/XADC/2022.1-2/Arty-A7-100-XADC-hw.xpr.zip|Arty-A7-100-Pmod-VGA-hw.xpr.zip}} | See //Using the Latest Release//, below |
| Arty A7-35 | 35/XADC/2021.1-1 | {{https://github.com/Digilent/Arty-A7/releases/download/35/XADC/2021.1-1/Arty-A7-35-XADC-hw.xpr.zip|Arty-A7-35-XADC-hw.xpr.zip}} | See //Using the Latest Release//, below |
| Arty A7-100 | 100/XADC/2021.1-1 | {{https://github.com/Digilent/Arty-A7/releases/download/100/XADC/2021.1-1/Arty-A7-100-XADC-hw.xpr.zip|Arty-A7-100-XADC-hw.xpr.zip}} | See //Using the Latest Release//, below |
| Arty A7-35 | 35/XADC/2020.1-1 | {{https://github.com/Digilent/Arty-A7/releases/download/35/XADC/2020.1-1/Arty-A7-35-XADC-hw.xpr.zip|Arty-A7-35-XADC-hw.xpr.zip}} | See //Using the Latest Release//, below |
| Arty A7-100 | 100/XADC/2020.1-1 | {{https://github.com/Digilent/Arty-A7/releases/download/100/XADC/2020.1-1/Arty-A7-100-XADC-hw.xpr.zip|Arty-A7-100-XADC-hw.xpr.zip}} | See //Using the Latest Release//, below |
| Arty A7-35 | v2018.2-1 | [[https://github.com/Digilent/Arty-A7-35-XADC/releases/tag/v2018.2-1|Release ZIP Downloads]] | [[https://github.com/Digilent/Arty-A7-35-XADC/tree/v2018.2-1|v2018.2-1 Github README]] |
| Arty A7-100 | v2018.2-1 | [[https://github.com/Digilent/Arty-A7-100-XADC/releases/tag/v2018.2-1|Release ZIP Downloads]] | [[https://github.com/Digilent/Arty-A7-100-XADC/tree/v2018.2-1|v2018.2-1 Github README]] |
**Note for Advanced Users:** //GitHub sources for this demo can be found in the [[https://github.com/digilent/arty-a7/tree/35/XADC/master|35/XADC/master]] and [[https://github.com/digilent/arty-a7/tree/100/XADC/master|100/XADC/master]] branches of the Arty-A7 repository. Further documentation on the structure of this repository can be found on this wiki's [[programmable-logic:documents:git]] page.//
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Instructions on the use of the latest release can be found in this dropdown:
--> Using the Latest Release ^#
{{page>programmable-logic:guides:using-github-releases#hardware_only_release_before_programming&noheader}}
--> Set up the Arty A7 #
Plug the microUSB programming cable into the Arty A7's PROG/UART port. Set up your circuit. In our case, we used a resistor ladder comprised of 8 1k ohm resistors.
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<--
{{page>programmable-logic:guides:using-github-releases#hardware_only_release_programming&noheader}}
At this point, the demo is now running on your board. Refer to the [[#description|Description]] and [[#functionality|Functionality]] sections of this document for more information on what it does.
<--
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===== Functionality =====
==== Applying a voltage to the XADC port ====
>
>For this demo, A0-A5 are single ended analog pins while A6-A7, A8-A9, and A10-A11 are differential ports.
>
**Warning:** Take care not to drive analog inputs below the Arty A7's ground or above 1.0V (for differential inputs) or above 3.3V (for single-ended inputs).
==== LEDs ====
>
>The LEDs turn on from right to left then wrap around the bottom as the input voltage increases.
>
>{{:reference:programmable-logic:arty-a7:demos:arty_xadc0.jpg?200|}}{{:reference:programmable-logic:arty-a7:demos:arty_xadc1.jpg?200|}}{{:reference:programmable-logic:arty-a7:demos:arty_xadc2.jpg?200|}}
==== Selecting a channel ====
>
>To display a different channel on the display and LEDs, change the user switches to the desired channel, as seen in the table below.
^ Channel Pin/s ^ SW3 ^ SW2 ^ SW1 ^ SW0 |
| A0 | Down | Down | Down | Down |
| A1 | Down | Down | Down | Up |
| A2 | Down | Down | Up | Down |
| A3 | Down | Down | Up | Up |
| A4 | Down | Up | Down | Down |
| A5 | Down | Up | Down | Up |
| A6-A7 | Down | Up | Up | Down |
| A8-A9 | Down | Up | Up | Up |
| A10-A11 | Up | Down | Down | Down |
| V_P-V_N | Up | Down | Down | Up |
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===== Additional Resources =====
All materials related to the use of the Arty A7 can be found on its [[..:start|Resource Center]].
For a walkthrough of the process of creating a simple HDL project in Vivado, see [[programmable-logic:guides:getting-started-with-vivado]]. Information on important parts of the GUI, and indirect discussion of the steps required to modify, rebuild, and run this demo in hardware can also be found here.
For technical support, please visit the [[https://forum.digilent.com/forum/4-fpga/|FPGA]] section of the Digilent Forum.
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