Project:Arduino Rotary Encoder Menu System

I have recovered a number of ALPS rotary encoders from discarded industrial CRT monitors. I'm working on building a user interface menu system that makes use of the rotary encoders as the sole input technique.

Rotary Encoder Test Sketch With Interrupts (non-PWM)

 1 #define PIN_ENC1 2
 2 #define PIN_ENC2 3
 3 #define PIN_EBTN 4
 4 #define PIN_LED1 13
 5 static boolean moving=false;
 6 volatile unsigned int encValue = 0;
 7 unsigned int encValueTracking = 1;
 8 boolean enc1 = false;              
 9 boolean enc2 = false;
10 
11 // Here I'm messing around with button press durations - we could go to town here!
12 enum pressDuration { reallyQuickPress, shortPress, normalPress, longPress, veryLongPress };
13 long presses[] = { 40, 150, 300, 800, 1400 };
14 char* pressText[]={"really quick press!", "short press", "normal press", "long press", "very looooooooong press"};
15 
16 void setup() 
17 {
18   pinMode(PIN_ENC1, INPUT); 
19   pinMode(PIN_ENC2, INPUT); 
20   pinMode(PIN_EBTN, INPUT);
21   pinMode(PIN_LED1, OUTPUT);
22   digitalWrite(PIN_ENC1, HIGH);
23   digitalWrite(PIN_ENC2, HIGH);
24   digitalWrite(PIN_EBTN, HIGH);
25   Serial.begin(9600);
26   menuIntro();
27   attachInterrupt(0, intrEncChange1, CHANGE);
28   attachInterrupt(1, intrEncChange2, CHANGE);
29 }
30 
31 void intrEncChange1()
32 {
33   if(moving) 
34     delay(1);
35   if(digitalRead(PIN_ENC1) == enc1)
36     return;
37   enc1 = !enc1;
38   if(enc1 && !enc2) 
39     encValue += 1;
40   moving = false;
41 }
42 
43 void intrEncChange2()
44 {
45   if(moving) 
46     delay(1);
47   if(digitalRead(PIN_ENC2) == enc2)
48     return; 
49   enc2 = !enc2;
50   if(enc2 && !enc1) 
51     encValue -= 1;
52   moving = false;
53 }
54 
55 void loop() 
56 { 
57   static unsigned long btnHeld = 0;
58   moving = true;
59   if(encValueTracking != encValue){
60     Serial.print("encValue: ");
61     Serial.println(encValue, DEC);
62     encValueTracking = encValue;
63   }
64   // Upon button press...
65   if((digitalRead(PIN_EBTN) == LOW) && !btnHeld){
66     btnHeld = millis();
67     digitalWrite(PIN_LED1, HIGH);
68     Serial.print("pressed selecting: ");
69     Serial.println(encValue, DEC);
70   }
71   // Upon button release...
72   if((digitalRead(PIN_EBTN) == HIGH) && btnHeld){
73     long t = millis();
74     t -= btnHeld;
75     digitalWrite(PIN_LED1, LOW);
76     int dur = veryLongPress;
77     for(int i = 0; i<= veryLongPress; i++){
78       if(t > presses[i])
79          continue;
80       dur = i;
81       break;
82     }
83     
84     Serial.print("released selecting: ");
85     Serial.print(encValue, DEC);    
86     Serial.print(" (after ");
87     Serial.print(t, DEC);
88     Serial.print(" ms = ");
89     Serial.print(pressText[dur]);
90     Serial.println(")");
91     btnHeld = 0;
92   }
93 }
94 
95 void menuIntro()
96 {
97   Serial.println("Encoder Menu - blah, blah, blah");
98 }

multiple encoders

Try out http://code.google.com/p/adaencoder/ and PinChangeInt library (http://code.google.com/p/arduino-pinchangeint/) see...

http://arduino.cc/playground/Main/RotaryEncoders#Example14

See if it can cope with two encoders at rapid rate usage.

OK, working well --Michael Erskine 18:10, 29 July 2012 (EST)

Raspberry Pi menu for rotary encoder

When using the Raspberry Pi as the menu display system we need to do a few things to a stock raspbian install...

• auto login and start X: use option in raspi-config
• switch off screen blanking: /etc/lightdm/lightdm.conf in SeatDefaults section "xserver-command=X -s 0 -dpms"
• auto start application

Here I'm building a Perl Tk menu application prototype using Tk::Canvas. I haven't yet wired up the serial as I'm just trying out some graphic styles on the small PAL LCD screen.

Raspberry Pi menu for rotary encoder

  1 #!/usr/bin/perl -w
  2 use strict;
  3 use IO::Handle;
  4 autoflush STDOUT 1;
  5 autoflush STDERR 1;
  6 use tmstub;
  7 use Tk;
  8 #use Tk::FontDialog;
  9 my $title = 'piduino menu';
 10 my $version = "v0.2 2012-07-29";
 11 
 12 my $mw = new MainWindow();
 13 # PAL resolution 656x512@16
 14 $mw->overrideredirect(1);
 15 my ($scr_w, $scr_h) = $mw->maxsize();
 16 t "maxsize says: $scr_w x $scr_h";
 17 #~ $mw->geometry("656x512+0+0");
 18 $mw->geometry("680x540+0+0");
 19 #~ $mw->FullScreen;
 20 #~ $mw->geometry(($mw->maxsize())[0] .'x'.($mw->maxsize())[1] . "+0+0");
 21 my $c = $mw->Canvas(-bg => "yellow", -width => 680, -height => 540)->pack;
 22 # in theory we should be able to scroll infinitely but let's stick to something reasonable
 23 #$c->configure(-scrollregion => [0,0, 600, 400]);
 24 my $font = $mw->fontCreate('menufont', -family => 'Village', -size => 38, -weight=>'bold');
 25 
 26 my $menu_w = 400;
 27 my $menu_h = 100;
 28 
 29 # it don't work!
 30 #~ invisible_cursor();
 31 
 32 # warp pointer tests...
 33 $mw->after(100, sub {warp(20,20)});
 34 
 35 sub warp {
 36     my($x, $y) = @_;
 37     t "warp pointer to $x $y";
 38     $c->focus;
 39     $mw->eventGenerate("<Motion>",
 40       -when => 'head',
 41       -x => $x, -y => $y, -warp => 1
 42     );
 43 }
 44 
 45 # keybinding tests...
 46 $mw->bind('<KeyPress>' => \&print_keysym);
 47 
 48 sub print_keysym {
 49     my($widget) = @_;
 50     my $e = $widget->XEvent;    # get event object
 51     my($keysym_text, $keysym_decimal) = ($e->K, $e->N);
 52     print "keysym=$keysym_text, numeric=$keysym_decimal\n";
 53 }
 54 
 55 # hide cursor
 56 sub invisible_cursor {
 57     my $bitmapfile = Tk->findINC('trans_cur.xbm');
 58     my $maskfile   = Tk->findINC('trans_cur.mask');
 59     $mw->configure(-cursor => [ '@' . $bitmapfile, $maskfile, 'black', 'white' ] );
 60 }
 61 
 62 # handy font chooser
 63 #~ $mw->Button(
 64     #~ -font => $font, 
 65     #~ -text => "Font", 
 66     #~ -command => sub{choose_font()},
 67 #~ )->pack();
 68 
 69 # debug grid...
 70 $c->createGrid(0, 0, 10, 10);
 71 $c->createGrid(0, 0, 50, 50, -lines => 1, -dash => '-.');
 72 $c->createGrid(0, 0, 100, 100, -width => 3, -lines => 1);
 73 
 74 # TODO - load settings from file
 75 menubox("Music", 0, 0);
 76 menubox("Controls", 0, 1);
 77 menubox("Vehicle", 0, 2);
 78 menubox("System", 0, 3);
 79 menubox("Settings", 0, 3);
 80 # menubox("More...", 1, 0);
 81 
 82 #~ music selection
 83 #~ playlists
 84 #~ artists by name
 85 #~ albums
 86 #~ directories
 87 
 88 #~ controls
 89 #~ volume
 90 #~ bass
 91 #~ treble
 92 #~ balance
 93 #~ system reboot
 94 #~ system shutdown
 95 #~ app quit
 96 #~ app restart
 97 
 98 
 99 
100 sub menubox {
101     my($t, $mx, $my) = @_;
102     my $x1 = $mx * $menu_w;
103     my $y1 = $my * $menu_h;
104     my $x2 = $x1 + $menu_w;
105     my $y2 = $y1 + $menu_h;
106 
107     $c->createRectangle($x1, $y1, $x2, $y2, 
108         -fill => "blue", 
109         -activefill => "green", 
110         -outline => "green", 
111         -activeoutline => "orange",
112     );
113     $c->createText($x1 + ($menu_w/2), $y1+ ($menu_h/2), 
114         -text => "$t", 
115         -font => $font,
116         -fill => "black",
117     );
118 }
119 
120 
121 =for docs
122 
123 options: 
124 
125 * canvas width and height to cover the whole menu system
126 * sub-menus can't all be visible simultaneously so we'd have to hide them
127 * group items together
128 
129 do top level menu first
130 
131 menu level zero at 0,0
132 menu level one appears at 1*menu_w, selected item * menu_h
133 
134 
135 
136 =cut
137 
138 
139 
140 
141 sub choose_font
142 {
143 #    t $mw->GetDescriptiveFontName($font);
144     
145  #   my $f = $mw->FontDialog->Show( 
146         #-initfont => $font,
147         #-nicefont => 1
148  #   );
149  #   return unless defined $f;
150  #   $mw->RefontTree(-font => $f, -canvas => 1);
151  #   my $d = $mw->GetDescriptiveFontName($f);
152  #   t $d;
153  #   $font = $f;
154 
155 }
156 
157 
158 MainLoop();

OK, using adaencoder on the Pi-arduino bridge! The Arduino is just saying what it sees over serial.

Raspberry Pi menu for rotary encoder

 1 #include <PinChangeInt.h> // necessary otherwise we get undefined reference errors.
 2 #include <AdaEncoder.h>
 3 
 4 #define a_PINA 10
 5 #define a_PINB 11
 6 #define BTN 9
 7 #define LED 13
 8 #define b_PINA A3
 9 #define b_PINB A4
10 
11 int8_t clicks=0;
12 char id=0;
13 
14 void setup()
15 {
16   Serial.begin(9600); 
17   Serial.println("---------------------------------------");
18   pinMode(BTN, INPUT);
19   pinMode(LED, OUTPUT);
20   digitalWrite(BTN, HIGH);
21   AdaEncoder::addEncoder('a', a_PINA, a_PINB);
22   // AdaEncoder::addEncoder('b', b_PINA, b_PINB);  
23 }
24 
25 void loop()
26 {
27   static unsigned long btnHeld = 0;
28   encoder *thisEncoder;
29   thisEncoder=AdaEncoder::genie(&clicks, &id);
30   if (thisEncoder != NULL) {
31     thisEncoder=AdaEncoder::getFirstEncoder();
32 
33     Serial.print(id); 
34     Serial.print(':');
35     Serial.print(clicks, DEC);
36     if (clicks > 0) {
37       Serial.println(" UP");
38     }
39     if (clicks < 0) {
40       Serial.println(" DOWN");
41     }
42   }
43   // Upon button press...
44   if((digitalRead(BTN) == LOW) && !btnHeld){
45     btnHeld = millis();
46     digitalWrite(LED, HIGH);
47     Serial.println("pressed");
48 
49   }
50   // Upon button release...
51   if((digitalRead(BTN) == HIGH) && btnHeld){
52     long t = millis();
53     digitalWrite(LED, LOW);
54     Serial.print("released: (after ");
55     t -= btnHeld;
56     Serial.print(t, DEC);
57     Serial.println(" ms)");
58 
59     btnHeld = 0;
60   }
61 }