This project implements a LFSR where the D-type FFs (DFFs) are replaceded by configurable delay lines.

The configurable delay lines are implement using multiplexers and buffers. The buffers generate a delay line path and the multiplexer select differents paths according to its selection control signals. The selection control signals are generated by a conventional LFSR.
It's expected that this circuit act as either as a convencional LFSR, or as an oscillator, or as a chaotic oscilator, according to the path generated by each delay line.
To verify its functionality, four statistical tests from the NIST statistical suite are also implemented:
They are choosen because they require at least 100 bits sequence to test.
The implementations are based on the following works:
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| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | LFSR Configurator clock | NIST 01 test output | ALFSR _analog_ output 0 |
| 1 | ALFSR reset | NIST 02 test output | ALFSR _analog_ output 1 |
| 2 | NIST random bits input | NIST 03 test output | ALFSR _analog_ output 2 |
| 3 | Operation mode | NIST 04 test output | ALFSR _analog_ output 3 |
| 4 | NIST Global error output | ||
| 5 | LFSR Configurator output | ||
| 6 | ALFSR _digitalized_ output 3 | ||
| 7 | ALFSR _analog_ output 3 |