diff --git a/demo_site/6502.png b/demo_site/6502.png
new file mode 100644
index 0000000..ffcc415
Binary files /dev/null and b/demo_site/6502.png differ
diff --git a/demo_site/demo.js b/demo_site/demo.js
new file mode 100644
index 0000000..e65c24c
--- /dev/null
+++ b/demo_site/demo.js
@@ -0,0 +1,434 @@
+
+//2017-09-17 Jorge Chamorro Bieling, jorge@jorgechamorro.com
+
+window.onload= function boot () {
+
+
+    Array.prototype.shuffle= function shuffle (a,b,i) {
+        a= [];
+        b= this;
+        while (b.length) {
+            i= rnd(b.length);
+            a[a.length]= b[i];
+            b.splice(i,1);
+        }
+        return a;
+    };
+
+
+    function $ (id) { return document.getElementById(id) }
+
+
+    function rnd (i) {
+        return Math.floor(i* Math.random());
+    }
+        
+
+    [ 'homer 1.png',
+        'homer 2.png',
+        'homer 3.png',
+        'homer 4.png',
+        'homer 5.png',
+        'homer 6.png',
+        'homer 7.png',
+        'homer 8.png',
+        'f666.png',
+        '6502.png',
+        '6502.png',
+        '6502.png'].shuffle().forEach(setup);
+   
+
+    function setup (src) {        
+        
+            var div= document.createElement('div');
+            div.className= 'crop';
+            var canvas= div.appendChild(document.createElement('canvas'));
+            canvas.width= 280;
+            canvas.height= 192;
+            var img= document.createElement('img');
+            img.onload= function onload (h,v) {
+                img.onload= h= v= 0;
+                if ((img.width>280) && (img.height>192)) {
+                    h= rnd(img.width-280);
+                    v= rnd(img.height-192);
+                }
+                canvas.getContext('2d').drawImage(img, -h, -v);
+                div._hex= foto2hex(canvas);
+                div.onclick= function onclick () {
+                    var samples= silence(48000/10)+ idle_turbo();
+                    for (var i=0 ; i<8192 ; i+=256) {
+                        var hex= div._hex.substr(2*i, 2*256);
+                        samples+= sync_turbo();
+                        samples+= hex_to_samples_turbo(hex);
+                        samples+= idle_turbo();
+                    }
+                    samples+= silence(48000/10);
+                    play(samples);
+                }
+            };
+            img.src= src;
+            div._img= img;
+            div._canvas= canvas;
+            document.body.appendChild(div);
+        
+        function foto2hex (canvas) {
+            var data= canvas.getContext('2d').getImageData(0,0,280,192);
+            var bytes= [];
+            for (var y=0 ; y<192 ; y+=1) {
+                for (var x=0 ; x<280 ; x+=7) {
+                    var byte= 0;
+                    for (var i=6 ; i>=0 ; i-=1) {
+                        var pixel= data.data[4*((y*280)+(x+i))];
+                        byte= (2*byte)+ (pixel ? 1 : 0);
+                    }
+                    byte= byte.toString(16);
+                    while (byte.length<2) byte= '0'+ byte;
+                    bytes[get_hgr_offset(x,y)]= byte;
+                }
+            }
+            var hex= '';
+            for (var i=0 ; i<8192 ; i++) hex+= bytes[i] ? bytes[i] : '00';
+            return hex;
+        }
+
+        var hgr_offsets= [0, 1024, 2048, 3072, 4096, 5120, 6144, 7168, 128, 1152,
+            2176, 3200, 4224, 5248, 6272, 7296, 256, 1280, 2304, 3328, 4352,
+            5376, 6400, 7424, 384, 1408, 2432, 3456, 4480, 5504, 6528, 7552,
+            512, 1536, 2560, 3584, 4608, 5632, 6656, 7680, 640, 1664, 2688,
+            3712, 4736, 5760, 6784, 7808, 768, 1792, 2816, 3840, 4864, 5888,
+            6912, 7936, 896, 1920, 2944, 3968, 4992, 6016, 7040, 8064, 40, 1064,
+            2088, 3112, 4136, 5160, 6184, 7208, 168, 1192, 2216, 3240, 4264,
+            5288, 6312, 7336, 296, 1320, 2344, 3368, 4392, 5416, 6440, 7464,
+            424, 1448, 2472, 3496, 4520, 5544, 6568, 7592, 552, 1576, 2600, 
+            3624, 4648, 5672, 6696, 7720, 680, 1704, 2728, 3752, 4776, 5800,
+            6824, 7848, 808, 1832, 2856, 3880, 4904, 5928, 6952, 7976, 936, 
+            1960, 2984, 4008, 5032, 6056, 7080, 8104, 80, 1104, 2128, 3152,
+            4176, 5200, 6224, 7248, 208, 1232, 2256, 3280, 4304, 5328, 6352, 
+            7376, 336, 1360, 2384, 3408, 4432, 5456, 6480, 7504, 464, 1488, 
+            2512, 3536, 4560, 5584, 6608, 7632, 592, 1616, 2640, 3664, 4688,
+            5712, 6736, 7760, 720, 1744, 2768, 3792, 4816, 5840, 6864, 7888, 
+            848, 1872, 2896, 3920, 4944, 5968, 6992, 8016, 976, 2000, 3024,
+            4048, 5072, 6096, 7120, 8144];
+            
+        function get_hgr_offset (x,y) {
+            return hgr_offsets[y]+ Math.floor(x/7);
+        }
+        
+    }
+
+
+
+
+    
+// Audio cosas comunes
+
+var playing= [];
+var audio_context = new (window.AudioContext || window.webkitAudioContext)();    
+var sample_rate= audio_context.sampleRate;
+var invert= 0;
+
+function mute () {
+    while (playing.length) {
+        var f= playing.pop();
+        try { f() } catch (e) { ; }
+    }
+}
+
+
+function silence (how_much) {
+    var str= '';
+    while (how_much--) str+= '0';
+    return str;
+}
+
+
+function play (samples) {
+
+    mute();
+
+    var channels= 1;
+    var audio_buffer = audio_context.createBuffer(channels, samples.length, sample_rate);
+    var channel_data= audio_buffer.getChannelData(0);
+    var symbol2level= {H:1, h:0.5, 0:0, L:-1, l:-0.5};
+    for (var i=0 ; i<samples.length ; i++) {
+        var c= samples[i];
+        if (invert) {
+            if (c === 'L') c= 'H';
+            else if (c === 'H') c= 'L';
+        }
+        channel_data[i]= symbol2level[c];
+    }
+    var audio_node = audio_context.createBufferSource();
+    audio_node.buffer= audio_buffer;
+    audio_node.connect(audio_context.destination);
+    audio_node.onended= cleanup;
+    playing.push(cleanup);
+    console.log("START PLAY");
+    audio_node.start();
+
+    function cleanup () {
+        audio_node.disconnect(audio_context.destination);
+        //audio_context.suspend();
+        //audio_context.close();
+        var where= playing.indexOf(cleanup);
+        if (where >= 0) playing.splice(where, 1);
+        console.log("END PLAY");
+    };
+
+}
+
+
+
+
+
+
+
+// **** Audio turbo
+    
+function idle_turbo () {
+    return 'LLLLLLLLLLLLHHHHHHHHHHH';
+}
+
+function sync_turbo () {
+    return 'HHLLLLLLLLHHHHHHHLL';
+};
+
+function hex_to_samples_turbo (hex) {
+
+    hex= hex.toLowerCase();
+    var hex2value= { 0:0, 1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 
+                     8:8, 9:9, a:10, b:11, c:12, d:13, e:14, f:15 };
+    
+    var bin= '';
+    for (var i=0 ; i<hex.length ; i++) {
+        var nibble= hex2value[hex[i]].toString(2);
+        while (nibble.length<4) nibble= '0'+ nibble;
+        bin+= nibble;
+    }
+    hex= '';
+        
+    var manchester= '';
+    var bit2samples= { 0:'LLHH', 1:'HHLL' };
+    for (var i=0 ; i<bin.length ; i++) manchester+= bit2samples[bin[i]];
+    bin= '';
+    
+    var tweaked= '';
+    var hi_ctr= 0;
+    for (var i=0 ; i<manchester.length ; i++) {
+        var c= manchester[i];
+        if (c === 'L') {
+            for (var j=1 ; j<hi_ctr ; j++) c= 'H'+ c;
+            tweaked+= c;
+            hi_ctr= 0;
+        }
+        else hi_ctr+= 1;
+    }
+    for (var j=1 ; j<hi_ctr ; j++) tweaked+= 'H';
+    manchester= ''
+    
+    return tweaked;
+}
+
+
+
+
+
+
+
+
+// Audio normal
+
+
+function applesoft_hex_to_samples (hex) {
+
+    hex= hex.toLowerCase();
+    
+    //4s @770 + sync + bytes + eor(bytes)
+    
+    var samples= '';
+    samples+= silence(sample_rate/5);   //0.2 s
+    samples+= header_770_normal(4);
+    samples+= sync_bit_normal();
+    samples+= applesoft_header(hex);
+    samples+= end_cycle(samples);
+    samples+= extend_last(sample_rate/10, samples);
+    
+    samples+= header_770_normal(5);
+    samples+= sync_bit_normal();
+    
+    var eor= 0xff;
+    var hex2value= {0:0, 1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8, 
+                    9:9, a:10, b:11, c:12, d:13, e:14, f:15};
+    for (var i=0 ; (i+1)<hex.length ; i+=2) {
+        var hi_nibble= hex2value[hex[i]];
+        var lo_nibble= hex2value[hex[i+1]];
+        var byte= lo_nibble+ (16* hi_nibble);
+        eor^= byte;
+        samples+= byte_normal(byte);
+    }
+    samples+= byte_normal(eor);
+    samples+= end_cycle(samples);
+    samples+= extend_last(10, samples);
+    samples+= silence(sample_rate/5);   //0.2 s
+    
+    return samples;
+}
+
+
+function assembly_hex_to_samples (hex) {
+
+    hex= hex.toLowerCase();
+    
+    //4s @770 + sync + bytes + eor(bytes)
+    
+    var samples= '';
+    samples+= silence(sample_rate/5);   //0.2 s
+    samples+= header_770_normal(4);
+    samples+= sync_bit_normal();
+    
+    var eor= 0xff;
+    var hex2value= {0:0, 1:1, 2:2, 3:3, 4:4, 5:5, 6:6, 7:7, 8:8, 
+                    9:9, a:10, b:11, c:12, d:13, e:14, f:15};
+    for (var i=0 ; (i+1)<hex.length ; i+=2) {
+        var hi_nibble= hex2value[hex[i]];
+        var lo_nibble= hex2value[hex[i+1]];
+        var byte= lo_nibble+ (16* hi_nibble);
+        eor^= byte;
+        samples+= byte_normal(byte);
+    }
+    samples+= byte_normal(eor);
+    samples+= end_cycle(samples);
+    samples+= extend_last(10, samples);
+    samples+= silence(sample_rate/5);   //0.2 s
+    
+    return samples;
+}
+
+function header_770_normal (segundos) {
+    //~segundos @770 Hz
+    var samples= '';
+    var ciclos= 770*segundos;
+    var samples_por_semiciclo= Math.round(sample_rate/(770*2));
+    var samples_total= ciclos* (2*samples_por_semiciclo);
+    for (var i=0 ; i<samples_total ; i++) {
+        var bit= !(Math.floor(i/samples_por_semiciclo)%2);
+        samples+= bit ? 'H' : 'L';
+    }
+    return samples;
+}
+
+
+function sync_bit_normal () {
+    //1 pulso de 200µs + 1 pulso de 250µs
+    var samples= '';
+    var up= Math.round(sample_rate*200e-6);
+    var down= Math.round(sample_rate*250e-6);
+    for (var i=0 ; i<up ; i++) samples+= 'H';
+    for (var i=0 ; i<down ; i++) samples+= 'L';
+    return samples;
+}
+
+
+function bit_nomal (bit) {
+    var samples= '';
+    var len= Math.round(sample_rate* (+bit ? 500e-6 : 250e-6));
+    for (var i=0 ; i<len ; i++) samples+= 'H';
+    for (var i=0 ; i<len ; i++) samples+= 'L';
+    return samples;
+}
+
+
+function byte_normal (byte) {
+    var samples= '';
+    byte= byte.toString(2);
+    while (byte.length<8) byte= '0'+ byte;
+    for (var i=0 ; i<8 ; i++) samples+= bit_nomal(byte[i]);
+    return samples;
+}
+
+
+function applesoft_header (hex) {
+    var samples= '';
+    var eor= 0xff;
+    var lock= 0x80;
+    var len= (hex.length/2)-1;
+    var hi= Math.floor(len/256);
+    var lo= len%256;
+    eor^= lo;
+    samples+= byte_normal(lo);
+    eor^= hi;
+    samples+= byte_normal(hi);
+    eor^= lock;
+    samples+= byte_normal(lock);
+    samples+= byte_normal(eor);
+    return samples;
+}
+
+
+function end_cycle (samples) {
+    var last= samples[samples.length-1];
+    return (last === 'H') ? 'L' : 'H';
+}
+
+
+function extend_last (n, samples) {
+    var s= '';
+    var last= samples[samples.length-1];
+    for ( var i=0 ; i<n ; i++) s+= last;
+    return s;
+}
+
+
+var prgm_applesoft= "13080a00b938322c303a8c323038303a800000000a27272727272727272727";
+
+var prgm_assembly= "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";
+
+
+
+
+
+
+
+// Listeners
+
+(function setup_listeners () {
+
+    $("b_mute").onclick= mute;
+    
+    $("b_load_applesoft").onclick= function () {
+        play(applesoft_hex_to_samples(prgm_applesoft+prgm_assembly));
+    };
+
+    $("b_load_assembly").onclick= function () {
+        play(assembly_hex_to_samples(prgm_assembly));
+    };
+    
+    $("b_reset").onclick= function () {
+        var samples= '';
+        samples+= silence(sample_rate/10);
+        samples+= idle_turbo();
+        samples+= sync_turbo();
+        samples+= extend_last(10, samples);
+        samples+= silence(sample_rate/10);
+        play(samples);
+    };
+    
+    
+    $("b_invert").onclick= function () {
+        invert= !invert;
+        $("b_invert").value= invert ? 'NOW INVERTED' : 'NOW NOT INVERTED';
+    };
+    
+    $("b_reload").onclick= function () { location.reload() };
+    
+    $("b_github").onclick= function () { location.href= 'https://github.com/xk/Turbo-Cassette-for-the-Apple-II' };
+    
+    $("b_csa2").onclick= function () { location.href= 'https://groups.google.com/forum/#!topic/comp.sys.apple2/V_S7-0pv3CA/discussion' };
+    
+    $("b_loop").onclick= function () { alert('Sorry not yet.') };
+    
+    $("o_sample_rate").innerHTML= "Sample rate is "+ sample_rate+ " sps";
+})();
+
+
+};
\ No newline at end of file
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diff --git a/demo_site/index.html b/demo_site/index.html
new file mode 100644
index 0000000..7d5a6e9
--- /dev/null
+++ b/demo_site/index.html
@@ -0,0 +1,20 @@
+<!doctype html>
+
+<html><head>
+	<meta http-equiv="content-type" content="text/html; charset=utf-8">
+	<title>TURBO-CASSETTE DEMO</title>
+	<meta name="description" content="Apple II faster cassette transfer">
+	<meta name="keywords" content="6502 , Apple II, cassette, Jorge Chamorro">
+    <link rel="stylesheet" type="text/css" media="all" charset="utf-8" href="style.css">
+	<script src="demo.js"></script>
+</head><body><h1>TURBO-CASSETTE Demo</h1><h3 id="o_sample_rate">Sample rate is ¿?</h3><div>
+<input type="button" id="b_mute" value="  MUTE  ">
+<input type="button" id="b_load_applesoft" value=" ]LOAD  ">
+<input type="button" id="b_load_assembly" value=" *820.E3AR ">
+<input type="button" id="b_reset" value=" RESET ">
+<input type="button" id="b_invert" value=" NORMAL/INVERTED ">
+<input type="button" id="b_reload" value=" reload ">
+<input type="button" id="b_github" value=" goto github ">
+<input type="button" id="b_csa2" value=" goto c.s.a2 ">
+<input type="button" id="b_loop" value=" LOOP 4 EVER "></div>
+</body></html>
\ No newline at end of file
diff --git a/demo_site/style.css b/demo_site/style.css
new file mode 100644
index 0000000..39c2032
--- /dev/null
+++ b/demo_site/style.css
@@ -0,0 +1,49 @@
+body {
+    background-color: #002543;
+    color: #ffffff;
+    margin: 0;
+    zoom: 1.1;
+}
+
+.crop {
+    margin: 0;
+    margin-left: 10px;
+    margin-bottom: 10px;
+    width: 280px;
+    height: 192px;
+    overflow: hidden;
+    border: 2px solid white;
+    float: left;
+}
+
+img {
+	margin: 0;
+	padding: 0;
+}
+
+input {
+    margin: 10px;
+    padding: 5px;
+    font-size: 0.8em;
+}
+
+h1 {
+	font-family: arial,helvetica,sans-serif;
+	font-size: 32px;
+	color: white;
+	font-weight: normal;
+	letter-spacing: 2px;
+	margin: 3px;
+}
+
+h3 {
+	font-family: arial,helvetica,sans-serif;
+	font-size: 14px;
+	color: white;
+	font-weight: normal;
+	letter-spacing: 2px;
+	margin: 3px;
+}
+.crop:hover {
+    border: 2px solid #fdc632;
+}
diff --git a/src/receive_hgr_demo_site.s b/src/receive_hgr_demo_site.s
new file mode 100644
index 0000000..7fc29fe
--- /dev/null
+++ b/src/receive_hgr_demo_site.s
@@ -0,0 +1,655 @@
+
+; Apple II TURBO CASSETTE LOADER
+; 13569 bps @44100 sps
+; 14769 bps @48000 sps
+; Jorge Chamorro Bieling, SEPT 2017
+; jorge@jorgechamorro.com
+
+; See the thread "Gentlemen, 14+ kbps" @ comp.sys.apple2 :
+; https://groups.google.com/forum/#!topic/comp.sys.apple2/V_S7-0pv3CA/discussion
+; Source files: github.com/xk/Turbo-Cassette-for-the-Apple-II
+; Compile with: apple2.duckdns.org/assembler/
+; Connect the PC to the Apple II cassette in port, set the volume at 50% or more.
+; Transfer directly from the assembler page to the Apple II and then 820G
+; Go to the demo page at: apple2.duckdns.org/turbodemo/
+; Click on an image to xfer it
+; On the Apple II the space bar resets the decoder an clears the HGR screen, ESC quits.
+; Report issues on c.s.a2 or @ the github repo.
+
+*           = $820
+
+buffer      = $2000
+spkr        = $c030
+cout        = $fded
+hgr         = $f3e2
+bell        = $ff3a
+
+bits        = 8
+sync_min    = 9
+sync_max    = 9
+
+reset       jsr bell
+            sta $c010
+            jsr skookum
+            
+entry       jsr go
+            lda $c000
+            bmi key
+            bcs reset
+            jmp entry
+            
+key         sta $c010
+            and #$7f
+            cmp #27             ;ESC is quit
+            bne reset           ;any other key is reset
+            sta $c053
+            sta $c051
+            rts
+
+go          lda #>buffer
+            sta buffer_hi_1
+            sta buffer_hi_2
+            jmp sync
+
+last_sample
+.byte 0
+
+decode      ldx #0              ;x= buffer index
+            ldy #bits           ;y= bit number
+            sec                 ;C means last edge was a clock
+
+sample_lo   lda $c060           ;4
+            bmi short_lo        ;2..3
+sl_1        lda $c060           ;4
+            bmi short_lo        ;2..3
+sl_2        lda $c060           ;4
+            bmi short_lo        ;2..3
+sl_3        lda $c060           ;4
+            bmi short_lo        ;2..3
+sl_4        lda $c060           ;4
+            bmi short_lo        ;2..3
+sl_5        lda $c060           ;4
+            bmi short_lo        ;2..3
+sl_6        lda $c060           ;4
+            bmi short_lo        ;2..3
+w_hi_clk    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_1    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_2    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_3    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_4    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_5    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_6    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_7    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_8    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_9    lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_10   lda $c060           ;4
+            bmi clk_rising      ;2..3
+hi_clk_11   lda $c060           ;4
+            bmi clk_rising      ;2..3
+            jmp eof_frame
+
+
+short_lo    bcc clk_rising
+            clc
+            jmp sh_1
+clk_rising  clc                 ;2      rising edge es un 0
+.byte       $3e                 ;7 rol buffer,x        ;7
+.byte       <buffer
+buffer_hi_1
+.byte       >buffer
+            sec
+            dey
+            bne sh_2
+            inx
+            beq eof_frame
+            ldy #bits
+            jmp sh_3
+
+
+short_hi    bcc clk_falling     ;2..3
+            clc                 ;2
+            jmp sl_1            ;3
+clk_falling sec                 ;2      falling edge es un 1
+.byte       $3e                 ;7 rol buffer,x        ;7
+.byte       <buffer
+buffer_hi_2
+.byte       >buffer
+            sec
+            dey                 ;2
+            bne sl_2            ;2..3
+            inx
+            beq eof_frame
+            ldy #bits
+            jmp sl_3            ;4
+            
+
+sample_hi   lda $c060           ;4
+            bpl short_hi        ;2..3
+sh_1        lda $c060           ;4
+            bpl short_hi        ;2..3
+sh_2        lda $c060           ;4
+            bpl short_hi        ;2..3
+sh_3        lda $c060           ;4
+            bpl short_hi        ;2..3
+sh_4        lda $c060           ;4
+            bpl short_hi        ;2..3
+sh_5        lda $c060           ;4
+            bpl short_hi        ;2..3
+sh_6        lda $c060           ;4
+            bpl short_hi        ;2..3
+w_lo_clk    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_1    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_2    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_3    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_4    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_5    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_6    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_7    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_8    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_9    lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_10   lda $c060           ;4
+            bpl clk_falling     ;2..3
+lo_clk_11   lda $c060           ;4
+            bpl clk_falling     ;2..3
+            jmp eof_frame
+
+
+eof_frame   cpy #0
+            bne quit_err
+            cpx #0
+            bne quit_err
+ok          ldx buffer_hi_1
+            inx
+            cpx #$40
+            beq quit_ok
+            stx buffer_hi_1     ;self-modifying code FTW
+            stx buffer_hi_2
+            jmp sync
+            
+quit_err    sec
+            rts
+
+quit_ok     clc
+            rts
+
+
+;ALGORITMO DE SYNC:
+;1.- buscar un falling edge
+;2.- contar bucles hasta el próximo flanco
+;3.- si son más de sync_max o menos de sync_min goto 1
+;4.- si son entre sync_min y sync_max => ok, y si ocurren 2 seguidos => ok: Al final del segundo empiezan los datos.
+;5.- si el último pulso da error probablemente la señal esté invertida.
+;6.- los samples de los pulsos de sync serían LLLLLLLLHHHHHHHLL (8L7H2L)
+
+
+sync        lda spkr
+            ldx #sync_min
+            
+            lda $c060
+            sta last_sample
+wait_edge   lda $c000
+            bmi quit_err
+no_key      lda $c060
+            eor last_sample
+            bpl wait_edge
+            lda last_sample
+            bpl sync            ;buscamos falling edge
+            
+sync_1_1    dex
+            bmi sync_2          ;min length ok
+            lda $c060
+            bpl sync_1_1
+            bmi sync            ;too short
+            
+sync_2      ldx #sync_max
+sync_2_1    dex
+            bmi sync            ;too long
+            lda $c060
+            bpl sync_2_1
+            bmi sync_3
+            
+;1st pulse (LO) ok
+
+sync_3      ldx #sync_min
+sync_3_1    dex
+            bmi sync_4          ;min length ok
+            lda $c060
+            bmi sync_3_1
+            bpl sync            ;too short
+            
+sync_4      ldx #sync_max
+sync_4_1    dex
+            bmi sync            ;too long
+            lda $c060
+            bmi sync_4_1
+            jmp decode          ;2nd pulse (HI) ok
+
+skookum     jsr hgr
+            sta $c052
+            lda #1
+            sta $3a9a
+            sta $263a
+            sta $2dba
+            sta $24c1
+            sta $3719
+            sta $20c1
+            sta $2442
+            sta $3737
+            sta $3d3d
+            sta $223a
+            sta $339b
+            sta $3f9b
+            sta $28bb
+            sta $3b9b
+            sta $3b37
+            sta $3a36
+            sta $29ba
+            sta $3e9a
+            sta $3042
+            sta $3e36
+            sta $379b
+            sta $2cbb
+            lda #2
+            sta $20bd
+            sta $33b7
+            lda #3
+            sta $23b7
+            sta $3ab7
+            sta $303f
+            sta $3a38
+            sta $2842
+            sta $203f
+            sta $271a
+            sta $3e38
+            sta $22bb
+            sta $36b7
+            sta $285e
+            sta $30bb
+            sta $29bc
+            sta $24bd
+            sta $2c42
+            sta $2c3f
+            sta $283f
+            sta $2b1a
+            sta $3638
+            sta $2a3a
+            sta $3b35
+            sta $3335
+            sta $26b6
+            sta $22b8
+            sta $26b8
+            sta $2dbc
+            sta $34bb
+            sta $2e3a
+            sta $31bc
+            sta $243f
+            sta $3398
+            sta $2f35
+            sta $3f37
+            sta $22b6
+            sta $3735
+            sta $231a
+            lda #4
+            sta $3b38
+            lda #6
+            sta $2d3c
+            sta $293f
+            sta $3b97
+            sta $2798
+            sta $3f97
+            sta $293c
+            lda #7
+            sta $28bd
+            sta $2f1a
+            sta $2f98
+            sta $2ab6
+            sta $2eb7
+            sta $213f
+            sta $2b39
+            sta $2fb7
+            sta $3238
+            sta $21bd
+            sta $2e38
+            sta $2ab7
+            sta $38bb
+            sta $2ab8
+            sta $3f19
+            sta $2eb6
+            sta $2b98
+            sta $2f38
+            sta $2bb7
+            sta $3b98
+            sta $39bc
+            sta $3798
+            sta $2cbd
+            sta $32b7
+            sta $2b35
+            sta $245e
+            sta $343f
+            sta $27b7
+            sta $2eb8
+            sta $35bc
+            sta $331a
+            sta $3cbb
+            sta $323a
+            sta $3e3b
+            sta $3b19
+            lda #8
+            sta $2cbc
+            lda #12
+            sta $34bc
+            sta $3f1a
+            sta $30bc
+            lda #14
+            sta $3c3f
+            sta $2a38
+            sta $3cbc
+            sta $3ab6
+            sta $38bc
+            sta $223c
+            sta $36b8
+            sta $253c
+            sta $213c
+            sta $2799
+            sta $3b1a
+            sta $313c
+            sta $34bd
+            sta $2040
+            sta $263c
+            sta $36b6
+            sta $371a
+            sta $30bd
+            sta $253b
+            lda #15
+            sta $2739
+            sta $3dbc
+            sta $3d3e
+            sta $3a3b
+            sta $3eb7
+            sta $32b8
+            sta $205e
+            sta $383f
+            sta $253f
+            sta $3f98
+            sta $3338
+            sta $213b
+            sta $2399
+            sta $32b6
+            sta $363a
+            lda #24
+            sta $37b6
+            sta $2299
+            sta $239a
+            sta $279a
+            lda #28
+            sta $263b
+            sta $2a3b
+            sta $28bf
+            sta $383e
+            sta $39bb
+            sta $343e
+            sta $2d3b
+            sta $3dbb
+            sta $2f99
+            sta $2fb6
+            sta $2336
+            sta $3eb6
+            sta $24bf
+            sta $3cbd
+            sta $2dbd
+            sta $323b
+            sta $35bb
+            sta $2e3b
+            sta $3bb6
+            sta $2699
+            sta $223b
+            sta $2840
+            lda #30
+            sta $293b
+            sta $38bd
+            sta $2bb6
+            sta $2b99
+            sta $2398
+            sta $3fb6
+            sta $2440
+            sta $20bf
+            sta $3738
+            sta $3ab8
+            sta $353c
+            sta $363b
+            lda #31
+            sta $2339
+            sta $393e
+            sta $3a3a
+            sta $25bd
+            sta $2337
+            lda #48
+            sta $3eb5
+            lda #56
+            sta $3639
+            sta $353b
+            sta $20be
+            sta $3799
+            sta $3c3e
+            sta $2e99
+            sta $3040
+            sta $33b6
+            sta $253d
+            sta $3ab9
+            sta $393b
+            sta $3a39
+            lda #57
+            sta $30bf
+            sta $2cbf
+            lda #60
+            sta $213d
+            sta $3399
+            sta $2c40
+            sta $313b
+            sta $3eb8
+            sta $3eb9
+            sta $2a99
+            lda #62
+            sta $29bd
+            sta $2335
+            lda #63
+            sta $2735
+            sta $313e
+            sta $353e
+            lda #64
+            sta $3cbe
+            sta $21b9
+            sta $3334
+            sta $2f34
+            sta $3734
+            sta $3041
+            sta $2c41
+            sta $3f34
+            sta $38be
+            sta $213e
+            sta $28bc
+            sta $38ba
+            sta $34ba
+            sta $28ba
+            sta $2b19
+            sta $26b5
+            sta $3b34
+            sta $25b9
+            sta $2ab5
+            sta $253e
+            sta $3637
+            sta $24bc
+            lda #65
+            sta $3337
+            sta $2042
+            lda #67
+            sta $25bc
+            sta $25ba
+            lda #68
+            sta $3a37
+            lda #70
+            sta $22b7
+            sta $3e37
+            lda #71
+            sta $26b7
+            lda #78
+            sta $31bb
+            sta $2c3e
+            lda #79
+            sta $2dbb
+            sta $23b6
+            lda #92
+            sta $3239
+            lda #94
+            sta $303e
+            sta $2e39
+            lda #95
+            sta $27b6
+            lda #96
+            sta $2cbe
+            sta $31b9
+            sta $3235
+            sta $29b9
+            sta $3e35
+            sta $2b97
+            sta $2719
+            sta $2841
+            sta $2f9a
+            sta $30be
+            sta $293e
+            sta $39b9
+            sta $3b36
+            sta $393d
+            sta $20c0
+            sta $24c0
+            sta $2cba
+            sta $28c0
+            sta $2441
+            sta $2319
+            sta $30ba
+            sta $243e
+            sta $35b9
+            sta $2db9
+            sta $285d
+            sta $3f9a
+            sta $353d
+            sta $22b5
+            sta $205d
+            sta $34be
+            lda #97
+            sta $2f37
+            sta $2b38
+            sta $3db9
+            lda #99
+            sta $21bc
+            lda #103
+            sta $29bb
+            sta $2239
+            sta $3f36
+            sta $25bb
+            lda #108
+            sta $283e
+            lda #111
+            sta $2a39
+            sta $2639
+            lda #112
+            sta $2738
+            sta $203e
+            sta $36b9
+            sta $2ab9
+            sta $3db8
+            sta $3718
+            sta $28be
+            sta $3f99
+            sta $24be
+            sta $2d3d
+            sta $3a99
+            sta $26b9
+            sta $3635
+            sta $3a35
+            sta $2041
+            sta $3e99
+            sta $3e39
+            sta $3336
+            sta $26ba
+            sta $3840
+            sta $339a
+            sta $3c40
+            sta $245d
+            sta $22b9
+            sta $2d3e
+            sta $379a
+            sta $32b9
+            sta $2eb9
+            sta $3b9a
+            sta $3699
+            sta $313d
+            sta $3736
+            lda #113
+            sta $3d3b
+            lda #115
+            sta $38bf
+            sta $21bb
+            lda #119
+            sta $3cbf
+            lda #120
+            sta $2238
+            sta $3b18
+            sta $2f36
+            sta $2338
+            sta $2b36
+            sta $293d
+            sta $3b99
+            sta $3440
+            sta $3299
+            sta $2f97
+            sta $2736
+            lda #121
+            sta $2b37
+            lda #123
+            sta $3d3c
+            sta $34bf
+            lda #124
+            sta $22ba
+            sta $3f18
+            sta $393a
+            sta $3397
+            lda #126
+            sta $393c
+            sta $2638
+            sta $3d3a
+            sta $3e3a
+            sta $3797
+            lda #127
+            sta $2737
+            sta $3f35
+            sta $21ba
+            sta $23b5
+            sta $27b5
+            rts
+
+.byte   0
+.byte   0
+.byte   0
+
+.end