Description: The final product is an array of 256 LEDs which could be used to display a multitude of information. It is also able to control, in a limited way, an iPod or other audio device. The design uses a clock module, temperature sensor, LED controllers, and a stereo volume control to provide the time, temperature, and audio entertainment which the user desires. Through the iPod, it is also possible to use it as an alarm clock.
Unfortunately I was not able to get everything fully functional at the same time, however individually everything worked.
Diagram of the Arduino-connected components
Materials Used:
Temperature sensor (thermistor)
DS1307 clock module (sparkfun breakout)
4 LED matrices
4 LED controllers (max7219)
1 Arduino
Power source (6A @ 5V)
2 grid style PCBs
1 double audio taper potentiometer (volume control)
2 audio jacks
1 power jack
connectors and wire
5 lbs solder
Case:
Masonite
Plexi
asst hardware
due to my mixed up wiring, i had to modify tomeks ledcontroller lib a little.
here are some code excerpts for showing temperature with two of the matrices connected.
note that this only lets you write 1 led/column, basically to do more than 1 you have to keep a buffer and add to it, then update each row later. this is what the LEDMatrix lib included with the arduino distro does.
anyway, the code below makes a little mountain which is taller the warmer the temperature
void loop () {
int temp = analogRead(tpin);
//what you write goes here mat(row,col); maxx is literal, mat translates
if (temp 0){
kh(1);
}
if (temp 294){
kh(2);
}
if (temp 339){
kh(3);
}
if (temp 384){
kh(4);
}
if (temp 429){
kh(5);
}
if (temp 474){
kh(6);
}
if (temp 521){
kh(7);
}
if (temp 564){
kh(8);
}
else{
kh(9); //light them all
}
}
void kh(int minn){//build a mountain
for (e=minn; e= minn
maxx(d[e],0);
maxx(d[minn],0); //pushes the last clear through to the second matrix
}
for (e=1; e<minn; e++){ //turn on the rows <min
mat(e,e);
mat(e, 17-e);
}
}
heres my code for writing to two matrices:
void mat(int reg, int col){ //can address row 1-8, col 1-16
digitalWrite(load, LOW);
if (col <= 8){//this writes the lower rows to the second matrix
putByte(d[reg]);
putByte(c[col]);
putByte(0x00);
putByte(0x00);
}
else{//this subtracts 8 and writes the higher rows to the first matrix
putByte(d[reg]);
putByte(c[col-8]);
}
digitalWrite(load, HIGH);
}
I managed to lose the .ai of the poster I made for the final presentation, but it was just name, title, and abstract
