Refactor and clean up Cylon.IO.DigitalPin class

This commit is contained in:
Andrew Stewart 2014-03-14 16:06:32 -07:00
parent e7f96b8a6c
commit 70dde8148c
1 changed files with 66 additions and 80 deletions

View File

@ -6,11 +6,11 @@
* Licensed under the Apache 2.0 license.
*/
'use strict';
"use strict";
var FS = require('fs');
var EventEmitter = require('events').EventEmitter;
var namespace = require('node-namespace');
var FS = require('fs'),
EventEmitter = require('events').EventEmitter,
namespace = require('node-namespace');
// DigitalPin class offers an interface with the Linux GPIO system present in
// single-board computers such as a Raspberry Pi, or a BeagleBone
@ -19,8 +19,10 @@ namespace("Cylon.IO", function() {
subclass(DigitalPin, klass);
var GPIO_PATH = "/sys/class/gpio";
var GPIO_READ = "in";
var GPIO_WRITE = "out";
var HIGH = 1;
var LOW = 0;
@ -32,47 +34,45 @@ namespace("Cylon.IO", function() {
}
DigitalPin.prototype.connect = function(mode) {
var _this = this;
if (mode == null) {
mode = null;
}
if (this.mode == null) {
this.mode = mode;
}
return FS.exists(this._pinPath(), function(exists) {
if (exists) {
return _this._openPin();
} else {
return _this._createGPIOPin();
}
var self = this;
if (this.mode == null) { this.mode = mode; }
FS.exists(this._pinPath(), function(exists) {
exists ? self._openPin() : self._createGPIOPin();
});
};
DigitalPin.prototype.close = function() {
var _this = this;
return FS.writeFile(this._unexportPath(), "" + this.pinNum, function(err) {
return _this._closeCallback(err);
var self = this,
num = this.pinNum.toString();
FS.writeFile(this._unexportPath(), num, function(err) {
self._closeCallback(err);
});
};
DigitalPin.prototype.closeSync = function() {
FS.writeFileSync(this._unexportPath(), "" + this.pinNum);
return this._closeCallback(false);
var num = this.pinNum.toString();
FS.writeFileSync(this._unexportPath(), num);
this._closeCallback(false);
};
DigitalPin.prototype.digitalWrite = function(value) {
var _this = this;
if (this.mode !== 'w') {
this._setMode('w');
}
if (this.mode !== 'w') { this._setMode('w'); }
var self = this;
this.status = value === 1 ? 'high' : 'low';
FS.writeFile(this._valuePath(), value, function(err) {
if (err) {
return _this.emit('error', "Error occurred while writing value " + value + " to pin " + _this.pinNum);
self.emit('error', "Error occurred while writing value " + value + " to pin " + self.pinNum);
} else {
return _this.emit('digitalWrite', value);
self.emit('digitalWrite', value);
}
});
return value;
};
@ -83,112 +83,98 @@ namespace("Cylon.IO", function() {
//
// Returns the defined interval
DigitalPin.prototype.digitalRead = function(interval) {
var readData,
_this = this;
if (this.mode !== 'r') {
this._setMode('r');
}
readData = null;
return every(interval, function() {
return FS.readFile(_this._valuePath(), function(err, data) {
var self = this;
if (this.mode !== 'r') { this._setMode('r'); }
every(interval, function() {
FS.readFile(self._valuePath(), function(err, data) {
if (err) {
return _this.emit('error', "Error occurred while reading from pin " + _this.pinNum);
var error = "Error occurred while reading from pin " + self.pinNum;
self.emit('error', error);
} else {
readData = parseInt(data.toString());
return _this.emit('digitalRead', readData);
var readData = parseInt(data.toString());
self.emit('digitalRead', readData);
}
});
});
};
DigitalPin.prototype.setHigh = function() {
return this.digitalWrite(1);
};
DigitalPin.prototype.setLow = function() {
return this.digitalWrite(0);
};
DigitalPin.prototype.setHigh = function() { return this.digitalWrite(1); };
DigitalPin.prototype.setLow = function() { return this.digitalWrite(0); };
DigitalPin.prototype.toggle = function() {
if (this.status === 'low') {
return this.setHigh();
} else {
return this.setLow();
}
return (this.status === 'low') ? this.setHigh() : this.setLow();
};
// Creates the GPIO file to read/write from
DigitalPin.prototype._createGPIOPin = function() {
var _this = this;
return FS.writeFile(this._exportPath(), "" + this.pinNum, function(err) {
var self = this,
num = this.pinNum.toString();
FS.writeFile(this._exportPath(), num, function(err) {
if (err) {
return _this.emit('error', 'Error while creating pin files');
self.emit('error', 'Error while creating pin files');
} else {
return _this._openPin();
self._openPin();
}
});
};
DigitalPin.prototype._openPin = function() {
this._setMode(this.mode, true);
return this.emit('open');
this.emit('open');
};
DigitalPin.prototype._closeCallback = function(err) {
if (err) {
return this.emit('error', 'Error while closing pin files');
this.emit('error', 'Error while closing pin files');
} else {
return this.emit('close', this.pinNum);
this.emit('close', this.pinNum);
}
};
// Sets the mode for the GPIO pin by writing the correct values to the pin reference files
DigitalPin.prototype._setMode = function(mode, emitConnect) {
var _this = this;
if (emitConnect == null) {
emitConnect = false;
}
if (emitConnect == null) { emitConnect = false; }
this.mode = mode;
if (mode === 'w') {
return FS.writeFile(this._directionPath(), GPIO_WRITE, function(err) {
return _this._setModeCallback(err, emitConnect);
var self = this,
data = (mode === 'w') ? GPIO_WRITE : GPIO_READ;
FS.writeFile(this._directionPath(), data, function(err) {
self._setModeCallback(err, emitConnect);
});
} else if (mode === 'r') {
return FS.writeFile(this._directionPath(), GPIO_READ, function(err) {
return _this._setModeCallback(err, emitConnect);
});
}
};
DigitalPin.prototype._setModeCallback = function(err, emitConnect) {
if (err) {
return this.emit('error', "Setting up pin direction failed");
this.emit('error', "Setting up pin direction failed");
} else {
this.ready = true;
if (emitConnect) {
return this.emit('connect', this.mode);
}
if (emitConnect) { this.emit('connect', this.mode); }
}
};
DigitalPin.prototype._directionPath = function() {
return "" + (this._pinPath()) + "/direction";
return this._pinPath() + "/direction";
};
DigitalPin.prototype._valuePath = function() {
return "" + (this._pinPath()) + "/value";
return this._pinPath() + "/value";
};
DigitalPin.prototype._pinPath = function() {
return "" + GPIO_PATH + "/gpio" + this.pinNum;
return GPIO_PATH + "/gpio" + this.pinNum;
};
DigitalPin.prototype._exportPath = function() {
return "" + GPIO_PATH + "/export";
return GPIO_PATH + "/export";
};
DigitalPin.prototype._unexportPath = function() {
return "" + GPIO_PATH + "/unexport";
return GPIO_PATH + "/unexport";
};
return DigitalPin;