Lab 4 - Introduction to Sequence Detectors and Coolrunner CPLDs

Objectives:

Implement a sequence recognizer that will identify or detect a specific sequence of highs and lows using ISE software and then transfer the project to a Coolrunner CPLD. The tutorial will take you from start to finish through an entire project. You will then be required to repeat the process with a different sequence.

Sequence Recognizer and Xilinx Coolrunner CPLD.

The tutorial will take you from start to finish for a sequence detector that will recognize the sequence 10010. It is strongly recommended that you go slowly and completely through the entire tutorial before you begin your assignment.

Your assignment is to write the VHDL code for a sequence recognizer that will recognize the sequence 1010. You will need to write the VHDL, the test bench (make your simulation look similar to mine in the tutorial), program the CPLD and then demonstrate it for your TA. It is not critical that you use the same time constraints as the tutorial in your simulation. What is critical is that you note that as long as your reset is high, you stay in state A (your initial state). Once your reset drops and you get a rising edge on your clock, you run your sequence through and verify that your code transitions through each of the states and finally causes your output to go high. Another thing to pay particular attention to is the fact that you only have one state high at a time (Z is not a state). This is called one hot. The deliverables for this portion of the project are listed below. It would behoove you to read the deliverables and the worksheet before you start the tutorial so that you know what you are going to be looking for.

Deliverables for lab 4

1. Your VHDL code for your sequence detector for 1010.
2. Your VHDL code for your test bench for 1010.
3. Your simulation waveforms showing similar results to what is presented in the tutorial.
4. Within your Fitter Report, what percentage of your macro cells were
   used?
5. Demonstrate your 1010 detector to your TA.
6. When you are done restore the XCR board to it's self test programming. Go to the ISE software and perform, file, open project. Browse on the C drive and look for a directory called XCRTEST. Open the file and start the project. You will not have to do anything else but the final programming step with iMPACT. Once you see it counting from 0-9, go ahead and switch off the power.
7. Worksheet