void sendto (float x_target, float y_target);
void do_pwm();
void hold(long length);
void laser_on();
void laser_off();
void draw_letter(byte letter);
float x_level;
float y_level;
float move_scale = 2.4;
int laser_pin = 12;
int x_speaker_pin = 5;
int y_speaker_pin = 6;
float exp_move = 2.7; //main value to adjust to change laser speed
//controls exponential laser movement
//lower values = faster drawing
//drawing too fast will decrease quality
//try setting it around 2.0 to 6
//this is the easiest variable to adjust to tweak quality vs. speed
float min_move = 0.5; //if the laser gets this close to its target location - (on both axis)
//it's considered close enough
//larger values increase drawing speed (at expense of quality)
//try setting it to about 0.5
float max_move = 30; //maximum allowed movement - helps keep things from moving too fast
//when drawing long lines
float laser_toggle_delay = 11; //extra delay in units of 20 us before toggling laser on / off - try 0 to 100
float line_delay = 8; //extra delay in units of 20 us at end of each line - try 0 to 100
float x_min_value = 5; //these set the minimum value for X and Y channels (on a scale of 0 to 255)
float y_min_value = 5; //this helps compensate for non-linear response some speakers have right off "center"
//these values must be below the corresponding max values
//increasing these values decrease image size
//try values of 0-30 - increase if you are having quality issues
float x_max_value = 190; //these set the minimum voltage for X and Y channels (on a scale of 0 to 255)
float y_max_value = 190; //this helps prevent the speaker from going outside its linear response range / distorting
//these values must be about the corresponding min values
//decreasing these values decrease image size
//try values of about 190 - decrease if you are having quality issues
//these values may also be manipulated to adjust the "aspect ratio"
void setup() {
pinMode(laser_pin, OUTPUT);
pinMode(x_speaker_pin, OUTPUT);
pinMode(y_speaker_pin, OUTPUT);
//resets the default arduino PWM stuff to much higher speed
setPwmFrequency(x_speaker_pin, 1);
setPwmFrequency(y_speaker_pin, 1);
}
//basic routines
//sendto (X,Y) - sends laser to X and Y coordinates - scale is always 0 to 255 (although actual resolution may be lower than this depending on above config values)
//move (X,Y) - moves laser to X and Y coordinates -relative- to current position
//move_scale = X - sets scaling - only used by "move" and "draw_letter" functions
//scaling of 2.8 allows for 5 characters across
//draw_letter("X") - draws single letter at single position (uppercase only - see routine for other supported characters)
//draw_string("STRING", X, Y, COUNT) - draws a string at X,Y for COUNT times
//marquee("HELLO WORLD", CHARACTERS) - draws a scrolling marquee CHARACTERS long - text is autoscaled to fit (4 to 7 characters long works best)
//laser_off() - turns laser off
//laser_on() - turns laser on
//hold(time) - tells laser to hold current position for roughly 20 microseconds (useful if you need to force laser to "catch up" after moving a large distance)
//put your laser control code here!
void loop()
{
//run the default laser show demo
demo();
}
void demo()
{
marquee("THIS ARDUINO LASER SHOW USES AUDIO SPEAKERS FOR GALVOS!", 5);
//star zoom in and out
for (float loop = 0; loop < 25; loop ++)
{
move_scale = loop / 5;
laser_off();
sendto (1,1);
move (17,5);
laser_on();
move (13,24);
move (-30,-18);
move (34,0);
move (-30,18);
move (13,-24);
}
for (float loop = 25; loop > 0; loop --)
{
move_scale = loop / 5;
laser_off();
sendto (1,1);
move (17,5);
laser_on();
move (13,24);
move (-30,-18);
move (34,0);
move (-30,18);
move (13,-24);
}
//"speed test"
move_scale = 1.8;
float exp_move_holder;
exp_move_holder = exp_move;
for (exp_move = 8; exp_move >= 1; exp_move = exp_move - exp_move / 20)
{
draw_string("SPEED", 1, 1, 1);
}
for (exp_move = 1; exp_move <= 8; exp_move = exp_move + exp_move / 20)
{
draw_string("TEST", 1, 1, 1);
}
exp_move = exp_move_holder;
//"pacman" demo - this code is very hacky...
move_scale = 2.3;
for (int x = 0; x < 10; x++)
{
draw_string("prrr", 1, 1, 2);
draw_string("qsss", 1, 1, 2);
}
draw_string("prrg", 1, 1, 2);
draw_string("qsg", 1, 1, 3);
draw_string("pg", 1, 1 , 3);
draw_string("q", 1, 1, 1);
draw_string("g", move_scale * 16 / 1.3, 1, 1);
draw_string("q", 1, 1, 1);
draw_string("g", move_scale * 16 / 1.4, 1, 1);
draw_string("ph", 1, 1, 3);
for (int x = 0; x < 6; x++)
{
draw_string("p", 1, 1, 5);
draw_string("q", 1, 1, 5);
}
marquee("LINK TO INSTRUCTABLE AT WWW.NOTHINGLABS.COM", 5);
}
void move (float x_movedir, float y_movedir)
{
x_movedir = x_movedir * move_scale;
y_movedir = y_movedir * move_scale;
sendto (x_level + x_movedir, y_level + y_movedir);
}
void sendto (float x_target, float y_target)
{
float x_move;
float y_move;
float temp_exp_move = exp_move;
while (fabs(x_target - x_level) > min_move || fabs(y_target - y_level) > min_move)
{
x_move = (x_target - x_level) / temp_exp_move;
y_move = (y_target - y_level) / temp_exp_move;
while (fabs(x_move) > max_move || fabs(y_move) > max_move)
{
x_move = x_move *.5;
y_move = y_move *.5;
temp_exp_move = temp_exp_move * 1.5;
}
x_level = x_level + x_move;
y_level = y_level + y_move;
do_pwm();
}
x_level = x_target;
y_level = y_target;
do_pwm();
hold(line_delay);
}
void laser_on()
{
hold(laser_toggle_delay);
digitalWrite(laser_pin, HIGH);
}
void laser_off()
{
hold(laser_toggle_delay);
digitalWrite(laser_pin, LOW);
}
void do_pwm()
{
//actual PWM code
float x_adjust;
float y_adjust;
//adds any offset (but still maintains 0-255 range) / handles scaling
x_adjust = x_min_value + (x_level * ((x_max_value - x_min_value) / 255));
y_adjust = y_min_value + ((y_level) * ((y_max_value - y_min_value) / 255));
if (x_adjust < 1) x_adjust = 1;
if (y_adjust < 1) y_adjust = 1;
if (x_adjust > x_max_value) x_adjust = x_max_value;
if (y_adjust > y_max_value) y_adjust = y_max_value;
analogWrite(y_speaker_pin, y_adjust);
analogWrite(x_speaker_pin, x_adjust);
}
void hold(long length)
{
long loop2 = 0;
length = length * 2;
while (loop2 < length)
{
delay (1); //we'v messed with timers - so this is a bunch smaller than 1ms delay
loop2 ++;
}
}
//void draw_string(char text[], int x, int y, int count)
void draw_string(String text, int x, int y, int count)
{
for (int loop = 0; loop < count; loop ++)
{
sendto (x,y);
int i = 0;
while (text.charAt(i) != '\0')
{
draw_letter(text.charAt(i));
i ++;
}
}
}
void marquee(String text, int characters)
{
float move_scale_holder;
int i = 0;
int loop = 0;
move_scale_holder = move_scale;
move_scale = 256 / (characters * 18);
for (int x=0; x < characters + 2; x++)
{
text = String(" " + text + " ");
}
for (loop = 0; loop < (text.length() - 5); loop ++)
{
draw_string(text.substring(loop,loop + characters),move_scale * 9,1,1);
draw_string(text.substring(loop,loop + characters),1,1,1);
}
move_scale = move_scale_holder;
}
void draw_letter(byte letter)
{
float temp_x_level = x_level;
float temp_y_level = y_level;
//all characters 16x16 (leave -plenty- of space on right side to prevent overlap with next character)
//characters are drawn starting from upper left corner
//"cursor" is automatically returned to top right corner
laser_off();
switch (letter)
{
case 'A':
move (0,16);
laser_on();
move (7,-16);
move (7,16);
laser_off();
move (-10,-7);
laser_on();
move (9,0);
break;
case 'B':
laser_on();
move (0,16);
move (11,-3);
move (-7,-5);
move (7,-5);
move (-11,-3);
break;
case 'C':
move (11,16);
laser_on();
move (-11,-2);
move (0,-12);
move (11,-2);
break;
case 'D':
laser_on();
move (0,16);
move (9,-4);
move (0,-8);
move (-9,-4);
break;
case 'E':
move (10,0);
laser_on();
move (-10,0);
move (0,14);
move (10,2);
laser_off();
move (-6,-10);
laser_on();
move (-6,0);
break;
case 'F':
move (10,0);
laser_on();
move (-10,0);
move (0,16);
laser_off();
move (0,-8);
laser_on();
move (5,0);
break;
case 'G':
move (9,8);
laser_on();
move (4,0);
move (-1,8);
move (-12,-2);
move (0,-12);
move (9,-2);
break;
case 'H':
move (2,0);
laser_on();
move (0,16);
laser_off();
move (0,-8);
laser_on();
move (9,0);
laser_off();
move (0,8);
laser_on();
move (0,-16);
break;
case 'I':
move (5,0);
laser_on();
move (0,16);
break;
case 'J':
move (0,8);
laser_on();
move (2,8);
move (9,0);
move (0,-16);
break;
case 'K':
laser_on();
move (0,16);
laser_off();
move (11,0);
laser_on();
move (-9,-8);
move (9,-8);
break;
case 'L':
laser_on();
move (0,16);
move (11,0);
break;
case 'M':
move (0,16);
laser_on();
move (0,-16);
move (7,8);
move (7,-8);
move (0,16);
break;
case 'N':
move (0,16);
laser_on();
move (0,-16);
move (11,16);
move (0,-16);
break;
case 'O':
laser_on();
move (11,0);
move (0,16);
move (-11,0);
move (0,-16);
break;
case 'P':
move (0,16);
laser_on();
move (0,-16);
move (11,4);
move (-11,4);
break;
case 'Q':
move (6,0);
laser_on();
move (-6,8);
move (6,8);
move (6,-8);
move (-6,-8);
laser_off();
move (0,7);
laser_on();
move (7,7);
break;
case 'R':
move (0,16);
laser_on();
move (0,-16);
move (11,3);
move (-11,5);
move (11,10);
break;
case 'S':
move (11,0);
laser_on();
move (-11,4);
move (11,6);
move (-11,6);
break;
case 'T':
laser_on();
move (13,0);
laser_off();
move (-8,0);
laser_on();
move (0,16);
break;
case 'U':
laser_on();
move (2,16);
move (9,0);
move (2,-16);
break;
case 'V':
laser_on();
move (5,16);
move (5,-16);
break;
case 'W':
laser_on();
move (3,16);
move (4,-8);
move (4,8);
move (3,-16);
break;
case 'X':
laser_on();
move (12,16);
laser_off();
move (-12,0);
laser_on();
move (12,-16);
break;
case 'Y':
laser_on();
move (6,7);
move (0,9);
laser_off();
move (0,-9);
laser_on();
move (6,-7);
break;
case 'Z':
laser_on();
move (12,0);
move (-12,16);
move (12,0);
break;
case ' ':
break;
case '-':
move (2,8);
laser_on();
move (10,0);
break;
case '\'':
move (8,0);
laser_on();
move (0,4);
break;
case '!':
move (5,0); //tweaked to make sure doesn't look like '?'
laser_on();
move (-1,3);
move (1,6);
laser_off();
move (0,5);
laser_on();
move (0,2);
break;
case '?':
laser_on();
move (12,1);
move (-6,6);
move (0,2);
laser_off();
move (0,5);
laser_on();
move (0,2);
break;
case '.':
move (5,14);
laser_on();
move (0,2);
move (0,-2);
break;
case '*':
move (5,8);
laser_on();
move (0,2);
move (0,-2);
break;
case ':':
move (5,2);
laser_on();
move (0,3);
laser_off();
move (0,5);
laser_on();
move (0,3);
break;
case '/':
move (0,16);
laser_on();
move (12,-16);
break;
case '0':
laser_on();
move (11,0);
move (0,16);
move (-11,0);
move (0,-16);
break;
case '1':
move (5,0);
laser_on();
move (0,16);
break;
case '2':
laser_on();
move (12,2);
move (-12,14);
move (12,0);
break;
case '3':
laser_on();
move (12,3);
move (-7,6);
move (7,6);
move (-12,3);
break;
case '4':
laser_on();
move (0,7);
move (12,0);
laser_off();
move (0,-7);
laser_on();
move (0,16);
break;
case '5':
move (0,16);
laser_on();
move (12,-5);
move (0,-5);
move (-12,0);
move (0,-6);
move (12,0);
break;
case '6':
move (0,6);
laser_on();
move (12,3);
move (0,6);
move (-12,1);
move (0,-16);
move (10,0);
break;
case '7':
laser_on();
move (12,0);
move (-10,16);
break;
case '8':
move (0,2);
laser_on();
move (12,12);
move (-6, 2);
move (-6,-2);
move (12,-12);
move (-6, -2);
move (-6, 2);
break;
case '9':
move (12,6);
laser_on();
move (-12,-3);
move (0,-3);
move (12,4);
move (0,12);
break;
//following characters are just for pacman demo
//pacman open
case 'p':
move (6,0);
laser_on();
move (6,2);
move (-6,6);
move (6,6);
move (-6,2);
move (-6,-8);
move (6,-8);
break;
//pacman closed
case 'q':
move (6,0);
laser_on();
move (6,7);
move (-7,1);
move (7,1);
move (-6,7);
move (-6,-8);
move (6,-8);
break;
//pellet 1
case 'r':
move (0,8);
laser_on();
move (0,2);
move (0,-2);
break;
//pellet 2
case 's':
move (9,8);
laser_on();
move (0,2);
move (0,-2);
break;
//ghost
case 'g':
move (8,0);
laser_on();
move (8,3);
move (0,13);
move (-4,-5);
move (-4,5);
move (-4,-5);
move (-4,5);
move (0,-13);
move (8,-3);
break;
//ghost gets eaten
case 'h':
move (-7,8);
laser_on();
move (3,3);
move (-6,-6);
move (3,3);
move (3,-3);
move (-6,6);
break;
}
//return to bottom right corner of character "cell" - adds 2 spaces
laser_off();
sendto (temp_x_level + (18 * move_scale) , temp_y_level);
}
/**
* Divides a given PWM pin frequency by a divisor.
*
* The resulting frequency is equal to the base frequency divided by
* the given divisor:
* - Base frequencies:
* o The base frequency for pins 3, 9, 10, and 11 is 31250 Hz.
* o The base frequency for pins 5 and 6 is 62500 Hz.
* - Divisors:
* o The divisors available on pins 5, 6, 9 and 10 are: 1, 8, 64,
* 256, and 1024.
* o The divisors available on pins 3 and 11 are: 1, 8, 32, 64,
* 128, 256, and 1024.
*
* PWM frequencies are tied together in pairs of pins. If one in a
* pair is changed, the other is also changed to match:
* - Pins 5 and 6 are paired.
* - Pins 9 and 10 are paired.
* - Pins 3 and 11 are paired.
*
* Note that this function will have side effects on anything else
* that uses timers:
* - Changes on pins 3, 5, 6, or 11 may cause the delay() and
* millis() functions to stop working. Other timing-related
* functions may also be affected.
* - Changes on pins 9 or 10 will cause the Servo library to function
* incorrectly.
*
* Thanks to macegr of the Arduino forums for his documentation of the
* PWM frequency divisors. His post can be viewed at:
* http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1235060559/0#4
*/
void setPwmFrequency(int pin, int divisor) {
byte mode;
if(pin == 5 || pin == 6 || pin == 9 || pin == 10) {
switch(divisor) {
case 1: mode = 0x01; break;
case 8: mode = 0x02; break;
case 64: mode = 0x03; break;
case 256: mode = 0x04; break;
case 1024: mode = 0x05; break;
default: return;
}
if(pin == 5 || pin == 6) {
TCCR0B = TCCR0B & 0b11111000 | mode;
} else {
TCCR1B = TCCR1B & 0b11111000 | mode;
}
} else if(pin == 3 || pin == 11) {
switch(divisor) {
case 1: mode = 0x01; break;
case 8: mode = 0x02; break;
case 32: mode = 0x03; break;
case 64: mode = 0x04; break;
case 128: mode = 0x05; break;
case 256: mode = 0x06; break;
case 1024: mode = 0x7; break;
default: return;
}
TCCR2B = TCCR2B & 0b11111000 | mode;
}
}
