diff --git a/Makefile b/Makefile
index 9557609..23b6b3a 100644
--- a/Makefile
+++ b/Makefile
@@ -2,8 +2,9 @@
 
 all: js/application.js js/preact.min.js | js
 
-js/application.js : src/main.jsx src/application.jsx
-	esbuild --bundle --jsx-factory=preact.h --format=esm src/main.jsx --outfile=js/application.js 
+js/application.js : src/main.jsx src/application.jsx src/note_input.jsx src/radio_group.jsx
+	esbuild --bundle --jsx-factory=preact.h --jsx-fragment=preact.Fragment --format=esm \
+	src/main.jsx --outfile=js/application.js 
 
 
 js/preact.min.js : node_modules/preact/dist/preact.min.js
diff --git a/css/application.css b/css/application.css
index 6ce6f9c..c03ca51 100644
--- a/css/application.css
+++ b/css/application.css
@@ -14,4 +14,16 @@ html {
 }
 sub {
 	font-style: italic;
+}
+
+legend a {
+	cursor: pointer;
+	display: inline-block;
+	margin-left: .5em;
+}
+legend a:last-of-type {
+	margin-right: .5em;
+}
+legend a.selected {
+	color: blue;
 }
\ No newline at end of file
diff --git a/src/application.jsx b/src/application.jsx
index d019218..b8b039d 100644
--- a/src/application.jsx
+++ b/src/application.jsx
@@ -1,11 +1,14 @@
 
 // var h = preact.h;
 
+import { NoteInput, NoteFrequency } from './note_input';
+import { RadioGroup } from './radio_group';
 
 
 function calc_sr(osc) {
 	// iigs is ~7.14Mhz / 8.  Mirage is 8Mhz / 8
-	return (28.63636*1000*1000/32) / (osc + 2);
+	// return (28.63636*1000*1000/32) / (osc + 2);
+	return (28_636_360/32) / (osc + 2);
 }
 
 function calc_shift(res,ws) {
@@ -18,12 +21,22 @@ function log2(x) {
 }
 
 
+var _onames = [];
 function Oscillators(props) {
 
-	var options = []
-	for (var i = 1; i < 33; ++i) {
-		options.push(<option value={i} key={i}>{i}</option>);
+	if (!_onames.length) {
+		for (var i = 1; i < 33; ++i) {
+			var x  = (calc_sr(i) / 1000 ).toFixed(2) + " kHz";
+			_onames.push(x)
+		}
 	}
+	var options = _onames.map( (x, ix) => {
+		var i = ix + 1;
+		return <option value={i} key={i}>{i} – {x}</option>
+	});
+	// for (var i = 1; i < 33; ++i) {
+	// 	options.push(<option value={i} key={i}>{i}</option>);
+	// }
 	return <select value={props.value} onChange={props.onChange}>{options}</select>;
 }
 
@@ -105,7 +118,53 @@ function SampleDisplay(props) {
 	return rv;
 }
 
+function SineWave() {
 
+	var rv = [];
+	for (n = 0; n < 256; ++n) {
+		var x = 128 + Math.round(127 * Math.sin(n * Math.PI / 128));
+		var y = x.toString(16); if (y.length < 2) y = "0" + y;
+		rv.push( y );
+		if ((n & 0x07) == 0x07) rv.push("\n");
+		else rv.push(', ');
+	}
+
+	return (
+		<code>
+		<pre>
+		{rv}
+		</pre>
+		</code>
+	);
+}
+function NoteDisplay(props) {
+
+
+	var { osc, wave, note } = props;
+
+	const sr = calc_sr(osc);
+	const note_frq = NoteFrequency(note);
+
+	const f = note_frq / (sr / (1 << (8 + wave)));
+
+	var best_res = 0;
+	var best_freq = 0;
+	for (var res = 0; res < 8; ++res) {
+		var tmp = f * (1 << calc_shift(res, wave));
+		if (tmp >= 0x10000) break;
+		best_res = res;
+		best_freq = tmp;
+	}
+
+	return (
+		<>
+			<div>Resolution: {best_res}</div>
+			<div>Frequency: {Math.round(best_freq)}</div>
+			<SineWave />
+		</>
+
+	);
+}
 
 // oscillators generate addresses, not samples.
 // accumulator is 24-bit.
@@ -122,8 +181,10 @@ export class Application extends preact.Component {
 		this._waveChange = this.waveChange.bind(this);
 		this._resChange = this.resChange.bind(this);
 		this._freqChange = this.freqChange.bind(this);
+		this._noteChange = this.noteChange.bind(this);
+		this._tabChange = this.tabChange.bind(this);
 
-		this.state = { osc: 32, wave: 0, res: 0, freq: 512 };
+		this.state = { osc: 32, wave: 0, res: 0, freq: 512, tab: 0, note: 4*12 };
 	}
 
 	oscChange(e) {
@@ -152,12 +213,22 @@ export class Application extends preact.Component {
 		this.setState( { freq: v } );
 	}
 
-	form() {
+	tabChange(v) {
+		this.setState({ tab: v });
+	}
+
+	noteChange(v) {
+		this.setState({ note: v });
+	}
+
+	sampleChildren() {
 
 		var { osc, wave, res, freq } = this.state;
 
+		var shift = calc_shift(res, wave);
+
 		return (
-			<div id="form">
+			<>
 				<div>
 					<label>Oscillators</label> <Oscillators value={osc} onChange={this._oscChange} />
 				</div>
@@ -170,36 +241,53 @@ export class Application extends preact.Component {
 				<div>
 					<label>Frequency</label> <Frequency value={freq} onChange={this._freqChange} />
 				</div>
-			</div>
+
+				<SampleDisplay freq={freq} shift={shift} />
+			</>
 		);
 	}
 
-	render() {
+	noteChildren() {
 
-		var { osc, wave, res, freq } = this.state;
-
-		var shift = calc_shift(res, wave);
+		var { osc, wave, note } = this.state;
 
 		return (
-			<div>
-				{ this.form() }
-
+			<>
 				<div>
-					Scan Rate: { (calc_sr(osc) / 1000 ).toFixed(2) } kHz
+					<label>Oscillators</label> <Oscillators value={osc} onChange={this._oscChange} />
+				</div>
+				<div>
+					<label>Wave Size</label> <WaveSize value={wave} onChange={this._waveChange} />
+				</div>
+				<div>
+					<label>Note</label> <NoteInput value={note} onChange={this._noteChange} />
 				</div>
 
-				<SampleDisplay freq={freq} shift={shift} />
-			</div>
+				<NoteDisplay osc={osc} note={note} wave={wave} />
+			</>
+		);
+
+	}
+
+
+	render() {
+
+		var { osc, wave, res, freq, tab } = this.state;
+
+		// var shift = calc_shift(res, wave);
+
+		var children;
+		switch(tab){
+			case 0: children = this.sampleChildren(); break;
+			case 1: children = this.noteChildren(); break;
+		}
+
+
+		return (
+			<RadioGroup value={tab} options={["Sample", "Note"]} onClick={this._tabChange }>
+				{ children }
+			</RadioGroup>
 		);
 	}
 }
 
-/*
-window.addEventListener('load', function(){
-
-    preact.render(
-        <Application />,
-        document.getElementById('application')
-    );
-});
-*/
diff --git a/src/note_input.jsx b/src/note_input.jsx
new file mode 100644
index 0000000..2449fc3
--- /dev/null
+++ b/src/note_input.jsx
@@ -0,0 +1,90 @@
+
+
+const _notes = ['C', 'C#', 'D', 'D#', 'E', 'F', 'F#', 'G', 'G#', 'A', 'A#', 'B'];
+
+const _base = [ 27.5, 55, 110, 220, 440, 880, ]
+
+function split_value(value) {
+	return [ value % 12, (value / 12) >> 0 ];
+}
+
+export function NoteName(value) {
+
+	var [note, octave] = split_value(value);
+
+	return _notes[note] + ' ' + octave;
+}
+
+export function NoteFrequency(value) {
+
+	var [note, octave] = split_value(value);
+
+	var n = (note + 3 ) % 12;
+	if (n >= 3) octave -= 1;
+	var base = 27.5 * (2 ** octave);
+
+	return base * 2 ** (n/12);
+}
+
+export class NoteInput extends preact.Component {
+	
+	constructor(props) {
+		super(props);
+
+		this._noteChange = this.noteChange.bind(this);
+		this._octaveChange = this.octaveChange.bind(this);
+
+	}
+
+	noteChange(e) {
+		e.preventDefault();
+
+		var [note, octave] = split_value(this.props.value);
+		note = +e.target.value;
+		this.change(note, octave);
+	}
+
+	octaveChange(e) {
+		e.preventDefault();
+
+		var [note, octave] = split_value(this.props.value);
+		octave = +e.target.value;
+		this.change(note, octave);
+	}
+
+	change(note, octave) {
+		var {onChange} = this.props;
+		if (onChange) {
+			var value = note + (12 * octave);
+			onChange(value);
+		}
+	}
+
+	render() {
+
+		var { onChange, value } = this.props;
+
+		var notes = _notes.map( (x, ix) => {
+			return <option key={ix} value={ix}>{x}</option>;
+		});
+
+		var octaves = [];
+		for (var i = 0; i < 8; ++i) {
+			octaves.push(
+				<option key={i} value={i}>{i}</option>
+			);
+		}
+
+		var [note, octave] = split_value(value);
+
+		return (
+			<>
+				<select onChange={this._noteChange} value={note}>{notes}</select>
+				{ ' ' }
+				<select onChange={this._octaveChange} value={octave}>{octaves}</select>
+				{ ' ' }
+				{ NoteFrequency(value).toFixed(2) } Hz
+		</>);
+	}
+
+}
diff --git a/src/radio_group.jsx b/src/radio_group.jsx
new file mode 100644
index 0000000..761acdc
--- /dev/null
+++ b/src/radio_group.jsx
@@ -0,0 +1,23 @@
+
+
+export function RadioGroup(props) {
+
+	var { options, value, onClick } = props;
+	var legend = [];
+	if (options) {
+
+		legend = options.map( (o, ix) => {
+			let _onClick = function(e) { e.preventDefault(); onClick(ix); }
+			return <a onClick={ _onClick } class={ ix == value ? "selected" : ""}>{o}</a>;
+		});
+
+	}
+
+	return (
+		<fieldset class="radio-group" id="form">
+			<legend>{legend}</legend>
+			{props.children}
+		</fieldset>
+	);
+
+}