Proximity alert test

Uses an ultrasonic sensor to detect proximity and flashes a led matrix when something enters in range.

This is a very simple project that uses an ultrasonic proximity sensor HC-SR04 to sense when something enters it's range. When some variation is detected, it uses a 8x8 led matrix module to flash a warnning.

There is an extra function (not used in this project) to display a digit in reverse on the matrix, note that if the line

myLeds.setLed(0, x, y, !bitRead(z, f));

is changed to

myLeds.setLed(0, x, y, bitRead(z, f));

the display is not reversed anymore.

The library does not contain a suitable part to display the led matrix module. The one I'm using have a matrix LD-1088AS mounted on a board with a MAX7219 controller. I don't know how to create a new part in the library so I had to use a 5 pin header to show how the wires are connected.

Disregard anything in the schematic and pcb view.