apla/avr-uart-calc.markdown

## avr-uart-calc.markdown

      
    Raw
  

              avr-uart-calc.markdown
            
          
    avr-uart-calc

A Pen by ivan baktsheev on CodePen.
License.

  
## index.html
<!DOCTYPE html>
<html lang="en">
  <head>
    <script type="module">

    </script>
  </head>
  <body>
    <main id="app"></main>
  </body>
</html>

## script.babel
// calculators
// http://www.wormfood.net/avrbaudcalc.php - server script, wont't work anymore
// https://trolsoft.ru/en/uart-calc - server script
// http://www.gjlay.de/helferlein/avr-uart-rechner.html - js
//
// TWI bitrate ???
// fuse calc ???

// registers
// http://maxembedded.com/2013/09/the-usart-of-the-avr/
// http://mainloop.ru/avr-atmega/avr-usart-setting.html

// import { h, app } from "https://unpkg.com/hyperapp"
const { h, app } = hyperapp;
/** @jsx h */

const state = {
	counter: 0,
	text: '',
	multiplier: 16,
	baudrate: '',
	frequency: 16*1000*1000
};

const _actions = {
	onBaudInput (evt) {
		return state => {
			return {baudrate: evt.target.value}
		}
	},
	onFreqInput (evt) {
		return state => {
			return {frequency: parseInt(evt.target.value)}
		}
	},
	onSpeedModCheck (evt) {
		return state => {
			return {
				multiplier: evt.target.value === "normal"
					? 16
					: evt.target.value === "double"
						? 8
						: 2}
		}
	}
};

function calcUBBRRaw (frequency, baudrate, multiplier) {
	return (frequency / ( baudrate * multiplier ) ) - 1
}

function calcUBBR (frequency, baudrate, multiplier) {
	return Math.trunc (calcUBBRRaw (frequency, baudrate, multiplier));
}

function calcUBBRError (frequency, baudrate, multiplier) {
	const rawUBBR = calcUBBRRaw (frequency, baudrate, multiplier);

	/*
	const hiUBBR = Math.floor (ubrr);
	const loUBBR = Math.ceil  (ubrr);
	bauda = f/(m*(hiUBBR+1));
	baudb = f/(m*(loUBBR+1));
	erra = bauda/baud-1;
	errb = baudb/baud-1;

	if (Math.abs (erra) < Math.abs (errb))
	{
		err = erra;
		ubrr = ubrra;
	}
	else
	{
		err = errb;
		ubrr = ubrrb;
	}
	*/

	return ((rawUBBR - Math.trunc (rawUBBR) ) / rawUBBR * 100);
}

/*
UBRR out of range                               // gray
UBRR and clock speed are a perfect match        // light green
UBRR and clock speed are less than 1% off       // green
UBRR and clock speed are between 1% and 2% off  // dark green
UBRR and clock speed are between 2% and 3% off  // yellow
UBRR and clock speed are between 3% and 10% off // orange
UBRR and clock speed is over 10% off            // red
*/
function calcUBBRColor (frequency, baudrate, multiplier) {
	const rawUBBR = calcUBBRRaw (frequency, baudrate, multiplier);
	return ((rawUBBR - Math.trunc (rawUBBR) ) / rawUBBR * 100);
}


function renderView (state, actions) {

	const baudrates = state.baudrate
		? state.baudrate.split(/\s,\s/).map (b => parseInt(b, 10))
		: [300, 1200, 9600, 19200, 57600, 115200, 230400, 250000];

	return <div class="row">
		<div class="column">
		{ /* <h1>{state.counter}</h1> */ }
		<h3>UBRR = ( FREQ / ( BAUDRATE * { state.multiplier } ) ) - 1</h3>
		<div>
			<input id="bps" type="text" oninput={evt => actions.onBaudInput(evt)}></input>
			<label for="bps">bps</label>
		</div>
		<div>
			<input id="freq" value={state.frequency} type="text" oninput={evt => actions.onFreqInput(evt)}></input>
			<label for="freq">Hz</label>
		</div>
		<div>
			<input name="speed-mod" value="normal" id="speed-mod-normal" type="radio" oninput={evt => actions.onSpeedModCheck(evt)} checked={state.multiplier === 16}></input>
			<label for="speed-mod-double">normal speed</label>
			<input name="speed-mod" value="double" id="speed-mod-double" type="radio" oninput={evt => actions.onSpeedModCheck(evt)} checked={state.multiplier === 8}></input>
			<label for="speed-mod-double">double speed</label>
			<input name="speed-mod" value="sync" id="speed-mod-sync" type="radio" oninput={evt => actions.onSpeedModCheck(evt)} checked={state.multiplier === 2}></input>
			<label for="speed-mod-sync">synchronous</label>
		</div>
		</div>{ /* column */ }
		<div class="column">
			<table>
				<tr>
					<th>Baud rate (bps)</th>
					<th>UBBR</th>
					<th>Error (%)</th>
				</tr>
					{baudrates.map (b => <tr>
						<td>{ b }</td>
						<td>{ calcUBBR (state.frequency, b, state.multiplier) }</td>
						<td>{ calcUBBRError (state.frequency, b, state.multiplier) }</td>
					</tr>)}
			</table>
		</div>
	</div>;
}

app(state, _actions, renderView, document.querySelector ('#app'));


## scripts
<script src="https://unpkg.com/hyperapp@1.x.x"></script>

## style.css
.row {
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  width: 100%;
}

.column {
  display: flex;
  flex-direction: column;
  flex-basis: 100%;
  flex: 1;
}
	<!DOCTYPE html>
	<html lang="en">
	<head>
	<script type="module">

	</script>
	</head>
	<body>
	<main id="app"></main>
	</body>
	</html>
	// calculators
	// http://www.wormfood.net/avrbaudcalc.php - server script, wont't work anymore
	// https://trolsoft.ru/en/uart-calc - server script
	// http://www.gjlay.de/helferlein/avr-uart-rechner.html - js
	//
	// TWI bitrate ???
	// fuse calc ???

	// registers
	// http://maxembedded.com/2013/09/the-usart-of-the-avr/
	// http://mainloop.ru/avr-atmega/avr-usart-setting.html

	// import { h, app } from "https://unpkg.com/hyperapp"
	const { h, app } = hyperapp;
	/** @jsx h */

	const state = {
	counter: 0,
	text: '',
	multiplier: 16,
	baudrate: '',
	frequency: 1610001000
	};

	const _actions = {
	onBaudInput (evt) {
	return state => {
	return {baudrate: evt.target.value}
	}
	},
	onFreqInput (evt) {
	return state => {
	return {frequency: parseInt(evt.target.value)}
	}
	},
	onSpeedModCheck (evt) {
	return state => {
	return {
	multiplier: evt.target.value === "normal"
	? 16
	: evt.target.value === "double"
	? 8
	: 2}
	}
	}
	};

	function calcUBBRRaw (frequency, baudrate, multiplier) {
	return (frequency / ( baudrate * multiplier ) ) - 1
	}

	function calcUBBR (frequency, baudrate, multiplier) {
	return Math.trunc (calcUBBRRaw (frequency, baudrate, multiplier));
	}

	function calcUBBRError (frequency, baudrate, multiplier) {
	const rawUBBR = calcUBBRRaw (frequency, baudrate, multiplier);

	/*
	const hiUBBR = Math.floor (ubrr);
	const loUBBR = Math.ceil (ubrr);
	bauda = f/(m*(hiUBBR+1));
	baudb = f/(m*(loUBBR+1));
	erra = bauda/baud-1;
	errb = baudb/baud-1;

	if (Math.abs (erra) < Math.abs (errb))
	{
	err = erra;
	ubrr = ubrra;
	}
	else
	{
	err = errb;
	ubrr = ubrrb;
	}
	*/

	return ((rawUBBR - Math.trunc (rawUBBR) ) / rawUBBR * 100);
	}

	/*
	UBRR out of range // gray
	UBRR and clock speed are a perfect match // light green
	UBRR and clock speed are less than 1% off // green
	UBRR and clock speed are between 1% and 2% off // dark green
	UBRR and clock speed are between 2% and 3% off // yellow
	UBRR and clock speed are between 3% and 10% off // orange
	UBRR and clock speed is over 10% off // red
	*/
	function calcUBBRColor (frequency, baudrate, multiplier) {
	const rawUBBR = calcUBBRRaw (frequency, baudrate, multiplier);
	return ((rawUBBR - Math.trunc (rawUBBR) ) / rawUBBR * 100);
	}



	function renderView (state, actions) {

	const baudrates = state.baudrate
	? state.baudrate.split(/\s,\s/).map (b => parseInt(b, 10))
	: [300, 1200, 9600, 19200, 57600, 115200, 230400, 250000];

	return <div class="row">
	<div class="column">
	{ /* <h1>{state.counter}</h1> */ }
	<h3>UBRR = ( FREQ / ( BAUDRATE * { state.multiplier } ) ) - 1</h3>
	<div>
	<input id="bps" type="text" oninput={evt => actions.onBaudInput(evt)}></input>
	<label for="bps">bps</label>
	</div>
	<div>
	<input id="freq" value={state.frequency} type="text" oninput={evt => actions.onFreqInput(evt)}></input>
	<label for="freq">Hz</label>
	</div>
	<div>
	<input name="speed-mod" value="normal" id="speed-mod-normal" type="radio" oninput={evt => actions.onSpeedModCheck(evt)} checked={state.multiplier === 16}></input>
	<label for="speed-mod-double">normal speed</label>
	<input name="speed-mod" value="double" id="speed-mod-double" type="radio" oninput={evt => actions.onSpeedModCheck(evt)} checked={state.multiplier === 8}></input>
	<label for="speed-mod-double">double speed</label>
	<input name="speed-mod" value="sync" id="speed-mod-sync" type="radio" oninput={evt => actions.onSpeedModCheck(evt)} checked={state.multiplier === 2}></input>
	<label for="speed-mod-sync">synchronous</label>
	</div>
	</div>{ /* column */ }
	<div class="column">
	<table>
	<tr>
	<th>Baud rate (bps)</th>
	<th>UBBR</th>
	<th>Error (%)</th>
	</tr>
	{baudrates.map (b => <tr>
	<td>{ b }</td>
	<td>{ calcUBBR (state.frequency, b, state.multiplier) }</td>
	<td>{ calcUBBRError (state.frequency, b, state.multiplier) }</td>
	</tr>)}
	</table>
	</div>
	</div>;
	}

	app(state, _actions, renderView, document.querySelector ('#app'));
	.row {
	display: flex;
	flex-direction: row;
	flex-wrap: wrap;
	width: 100%;
	}

	.column {
	display: flex;
	flex-direction: column;
	flex-basis: 100%;
	flex: 1;
	}