keep working on triangle

apu/apu.js

@@ -29,6 +29,19 @@ import Triangle from './triangle';
 // 4-step mode.  We never need to worry about IRQ.
 
 
+class Enabler {
+  constructor(id) {
+    const element = document.getElementById(id);
+    this.enabled = true;
+    if (element) {
+      element.addEventListener('click', () => {
+        this.enabled = element.checked;
+        console.log(id + ' => ' + this.enabled);
+      });
+    }
+  }  
+}
+
 export default class Apu {
   /**
    * @param {!Memory} mem
@@ -39,14 +52,20 @@ export default class Apu {
     this.clock_ = clock;
     this.pulse1_ = new Pulse(mem, 0x4000);
     this.pulse2_ = new Pulse(mem, 0x4004);
-    //this.triangle_ = new Triangle(mem);
+    this.triangle_ = new Triangle(mem);
     this.noise_ = new Noise(mem);
     this.steps_ = [];
     this.last_ = 0;
     this.wait_ = 2;
 
     this.frameCounter_ = 0;
 
+    this.pulse1Enabled = new Enabler('pulse1_enabled');
+    this.pulse2Enabled = new Enabler('pulse2_enabled');
+    this.triangleEnabled = new Enabler('triangle_enabled');
+    this.noiseEnabled = new Enabler('noise_enabled');
+
+
     // TODO - add a callback when volume changes, so we don't
     // need to keep recomputing the mixer every single time!
 
@@ -75,12 +94,11 @@ export default class Apu {
       // TODO - distinguish half from quarter frames.
       this.pulse1_.clockFrame();
       this.pulse2_.clockFrame();
-      //this.triangle_.clockFrame();
+      this.triangle_.clockFrame();
       this.noise_.clockFrame();
     }
 
-    //this.triangle_.clockSequencer(); // clocks every cycle
-
+    this.triangle_.clockSequencer(); // clocks every cycle
     if (!--this.wait_) {
       this.pulse1_.clockSequencer();
       this.pulse2_.clockSequencer();
@@ -110,13 +128,13 @@ export default class Apu {
   }
 
   volume() {
-    const pulse1 = this.pulse1_.volume();
-    const pulse2 = this.pulse2_.volume();
+    const pulse1 = this.pulse1Enabled.enabled ? this.pulse1_.volume() : 0;
+    const pulse2 = this.pulse2Enabled.enabled ? this.pulse2_.volume() : 0;
     const pulseOut = (pulse1 || pulse2) &&
         95.88 / (8128 / (pulse1 + pulse2) + 100);
 
-    const triangle = 0; // this.triangle_.volume();
-    const noise = this.noise_.volume();
+    const triangle = this.triangleEnabled.enabled ? this.triangle_.volume() : 0;
+    const noise = this.noiseEnabled.enabled ? this.noise_.volume() : 0;
     const dmc = 0; // this.dmc_.volume();
     const tndOut = (triangle || noise || dmc) &&
         159.79 / (1 / (triangle / 8227 + noise / 12241 + dmc / 22638) + 100);

apu/lengthcounter.js

@@ -5,7 +5,7 @@ export default class LengthCounter {
     /** @private @const {!Memory.Register<number>} */
     this.reload_ = mem.int(base + 3, 3, 5);
     /** @private {number} */
-    this.counter_ = 0;
+    this.counter_ = 1; // TODO - so that it's nonzero if it's never clocked...?
 
     /** @private {function()} */
     this.disableCallback_ = function() {};

apu/triangle.js

@@ -1,10 +1,8 @@
-/**
- * @fileoverview NES APU Emulator.
- */
-
 import Memory from '../mem';
 import LengthCounter from './lengthcounter';
 
+// TODO - this pops a lot - can we smooth it out?!?
+
 export default class Triangle {
   /**
    * @param {!Memory} mem
@@ -35,11 +33,22 @@ export default class Triangle {
     /** @private {number} */
     this.sequence_ = 0;
 
+
+    for (let i = 0x4008; i < 0x400C; i++) mem.listen(i, () => this.print());
+
     mem.listen(0x400B, () => this.linearCounterReloadFlag_ = true);
-    this.lengthCounter_.onDisable(() => this.volume_ = this.computeVolume_());
+    this.lengthCounter_.onDisable(() => this.volume_ = 0);
   }
 
-  print() {}
+  print() {
+    return;
+    console.log(`TRIANGLE
+linear ${this.linearCounter_} of ${this.linearCounterReloadValue_.get()}
+control ${this.control_.get()}
+sequence ${this.sequenceTimer_} of ${this.sequenceTimerPeriod_.get()} => ${this.sequence_}
+length ${this.lengthCounter_.enabled_.get()} ${this.lengthCounter_.counter_} ${this.lengthCounter_.reload_.get()}
+volume ${this.volume_}`);
+  }
 
   /**
    * @return {number} The value of the waveform, from 0 to 15 (?)
@@ -52,8 +61,10 @@ export default class Triangle {
    * @return {number} Computes the volume.
    */
   computeVolume_() {
-    return this.lengthCounter_.enabled() && this.linearCounter_ > 0 ?
-        WAVEFORM[this.linearCounter_] : 0;
+    const v = this.lengthCounter_.enabled() && this.linearCounter_ > 0 ?
+        WAVEFORM[this.sequence_] : 0;
+    //if (v == 15) console.log('TRIANGLE 15');
+    return v;
   }
 
   /**
@@ -63,21 +74,25 @@ export default class Triangle {
   clockFrame(quarter) {
     if (this.linearCounterReloadFlag_) {
       this.linearCounter_ = this.linearCounterReloadValue_.get();
-    } else if (this.linearCounter_ >= 0) {
+    } else if (this.linearCounter_ > 0) {
       this.linearCounter_--;
-      if (!this.linearCounter_) this.volume_ = this.computeVolume_();
+      if (!this.linearCounter_) this.volume_ = 0;
     }
 
     if (this.control_.get()) {
       this.linearCounterReloadFlag_ = false;
     }
+
+    if (quarter % 2 && !this.control_.get()) {
+      this.lengthCounter_.clock();
+    }
   }
 
   /** Clocks the sequencer. */
   clockSequencer() {
     if (this.sequenceTimer_ == 0) {
       this.sequence_ = (this.sequence_ + 1) % 32;
-      this.sequence_ = this.sequenceTimerPeriod_.get();
+      this.sequenceTimer_ = this.sequenceTimerPeriod_.get();
       this.volume_ = this.computeVolume_();
     } else {
       this.sequenceTimer_--;

index.html

@@ -6,4 +6,14 @@
 <input type="submit" id="stop" value="stop" style="display:none;">
 <input type="submit" id="next" value="next" style="display:none;">
 
+<div>
+  <input type="checkbox" id="pulse1_enabled" checked> Pulse 1: <span id="pulse1"></span>
+  <br>
+  <input type="checkbox" id="pulse2_enabled" checked> Pulse 2: <span id="pulse2"></span>
+  <br>
+  <input type="checkbox" id="triangle_enabled" checked> Triangle: <span id="triangle"></span>
+  <br>
+  <input type="checkbox" id="noise_enabled" checked> Noise: <span id="noise"></span>
+</div>
+
 <div id="log" style="white-space: pre; font-family: monospace;"></div>

nsfplayer.js

@@ -42,7 +42,8 @@ export default class NsfPlayer {
 
     if (this.promise != promise) return;
     if (this.node.bufferTime() == 0) console.log('buffer underrun!');
-    for (let i = 0; i < 100; i++) {
+    // TODO - use i < 100 and requestAnimationFrame to be smoother?!?
+    for (let i = 0; i < 10; i++) {
       for (let frameCycle = this.cyclesPerFrame; frameCycle >= 0; frameCycle--) {
         if (frameCycle != frameCycle) throw new Error('NaN');
         if (this.cpu.PC != 0xFFFF) this.cpu.clock();
@@ -59,7 +60,12 @@ export default class NsfPlayer {
         this.writer.write(this.apu.steps(), this.clock.time)
             //.then(() => this.play(promise));
             // .then(() => { setTimeout(() => this.play(promise), 0); });
-            .then(() => { requestAnimationFrame(() => this.play(promise)); });
+            // TODO(sdh): for some reason, requestAnimationFrame (and/or i<100)
+            // causes a weird glitch on the 2nd and later song...?!?
+            //.then(() => { requestAnimationFrame(() => this.play(promise)); });
+            .then(() => {
+              setTimeout(() => this.play(promise), 1000 * (this.node.bufferTime()) - 60);
+            });
     // console.log('Yield data', data);
   }