For years, designers have been taking advantage of the time-to-market benefits of designing their systems using Xilinx programmable logic devices. Now, Xilinx has made it even easier to beat your competition to the market by accelerating the process of in-system verification using PROBE. 

PROBE is an interactive tool that simplifies the process of observing the behavior of signals within an FPGA while operational in a target system.  As a result of the PROBE operation, you are able to use your existing test equipment to analyze the circuit's behavior in a manner that is familiar to you.

Xilinx began shipping PROBE as part of its Alliance and Foundation Series tools starting with the v2.1i products. The following sections show you how to take advantage of PROBE. 

PROBE Benefits

How to Use PROBE

As part of a larger suite of verification tools, PROBE is the most efficient tool for selecting internal signals as test points during board level analysis. Once these signals are brought out as test points, you can use your existing lab equipment to most efficiently debug your design. You do not have to learn how to operate new tools, so you can leverage your existing knowledge. Furthermore, you avoid the complications of linking the trigger points of your existing equipment to additional analysis tools. 

PROBE also provides you with the ultimate flexibility to identify the signals you want to analyze.  Given a set of reserved test points, you simply modify the signals you want to view on your logic analyzer (or oscilloscope) using the intuitive Graphical User Interface (GUI). With a push of a button, PROBE quickly completes the task of routing the chosen signal to your PROBE point. In many cases, you can merely leave your test leads on the boards test points, and use PROBE to  quickly and efficiently view different signals without having to touch the test equipment.

Using PROBE to debug your design is easy!

When you are creating your design, route the spare I/O from your Xilinx device to test points on your Printed Circuit Board. This makes it easy to attach test leads to these signal traces, and in circumstances where additional functionality is added to the Xilinx device, it also makes it easier to "blue wire" external signals to the chip as well.

Once you begin debugging the design and find that you need to look at a signal that is internal to the Xilinx device, it is a simple matter to identify this signal and the desired test point from within the PROBE dialog box. To start, open the design you want to test within the Xilinx FPGA Editor.

The following steps will show you how to use PROBE.
 

1) Invoke PROBE's dialog box using the simple toolbar menu pick.
2) Select Add within the PROBE dialog box.
3) Next, assign the PROBE name.
4) Choose the desired signal using the "Select Net" filter and browse function.
5) Assign the selected signal to a PROBE pin.
6) Push OK to have PROBE assign the signal to the device pin.  Of course, PROBE can assign multiple test points during each assignment operation (limited to the number of I/O reserved for PROBE's use).