
Install wiringpi to get the `gpio` command:

```
apt install wiringpi
```

There are five LEDs on the front.  The indicate which subsystems work.

1: An error occurred
2: Test Error
3: Test Error
4: Test Error
5: Tester is IDLE (also, tester is READY)

LEDs 2, 3, and 4 form a pattern that indicate which test failed:

Test name           | 2 (Green) | 3 (Blue)  | 4 (White) | Reason for Failure |
====================+===========+===========+===========+====================+
SPI Valid           |           |     x     |     x     | The SPI flash was not found, or was not the correct model |
USB Communication   |     x     |           |           | The FPGA isn't assembled correctly, the USB pullup isn't correct, or the crystal is bad |
Load Test Bitstream |           |           |           | The FPGA isn't assembled correctly |
Test SPI            |           |     x     |           | Not all four wires are connected between the FPGA and the SPI |
Test RGB            |     x     |     x     |           | TOUCH2 or the RGB LED are not assembled correctly |
Test Touch          |           |     x     |     x     | TOUCH1, TOUCH3, or TOUCH4 are not assembled correctly |
Final Bitstream     |           |           |     x     | The final program could not be loaded |
