MCP23017 read

lib/devices/MCP230xx.js

@@ -97,6 +97,38 @@ MCP230xx.prototype.pullup = function(pins, state, cb) {
   }
 };
 
+MCP230xx.prototype.inputAll = function(cb) {
+  var _self = this;
+  _self._readGPIO(function(err, value) {
+    if (err) return cb(err);
+    var pins = [];
+    for (var i = 0; i < _self.num_gpios; i++) {
+      pins[i] = !!(value & (1 << i));
+    }
+    cb(null, pins);
+  });
+};
+
+MCP230xx.prototype.input = function(pins, cb) {
+  var _self = this;
+  step(
+    function inputAll() {
+      _self.inputAll(this);
+    },
+    function processResults(err, vals) {
+      if (!Array.isArray(pins)) {
+        return cb(null, vals[pins]);
+      } else {
+        var result = [];
+        for (var i = 0, l = pins.length; i < l; i++) {
+          result.push(vals[pins[i]]);
+        }
+        cb(null, result);
+      }
+    }
+  );
+};
+
 MCP230xx.prototype.output = function(pins, value, cb) {
   var _self = this;
 
@@ -150,6 +182,42 @@ MCP230xx.prototype._setDirection = function(pins, dir, cb) {
   }
 };
 
+MCP230xx.prototype._readGPIO = function(cb) {
+  var _self = this;
+
+  var value = 0;
+  step(
+    function readRegisterA() {
+      _self._readU8(MCP23017_GPIOA, this);
+    },
+    function registerARead(err, lower) {
+      if (err) return cb(err);
+      value += lower;
+      this();
+    },
+    function readRegisterB() {
+      if (_self.num_gpios > 8) {
+        _self._readU8(MCP23017_GPIOB, this);
+      } else {
+        this();
+      }
+    },
+    function registerBRead(err, upper) {
+      if (err) return cb(err);
+      if (upper) {
+        value += (upper << 8);
+      }
+      this();
+    },
+    function done() {
+      if (cb) {
+        cb(null, value);
+      }
+      return;
+    }
+  );
+};
+
 MCP230xx.prototype._updateRegister = function(registerA, registerB, value, cb) {
   var _self = this;
 

main.js

@@ -1,4 +1,4 @@
 require('coffee-script');
-var i2c = require('./lib/i2c');
+var i2c = require('i2c');
 
-module.exports = i2c;
+module.exports = i2c;