1 #!/usr/bin/env node 2 3 /* 4 * Author: Brendan Le Foll <brendan.le.foll@intel.com> 5 * Copyright (c) 2014 Intel Corporation. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining 8 * a copy of this software and associated documentation files (the 9 * "Software"), to deal in the Software without restriction, including 10 * without limitation the rights to use, copy, modify, merge, publish, 11 * distribute, sublicense, and/or sell copies of the Software, and to 12 * permit persons to whom the Software is furnished to do so, subject to 13 * the following conditions: 14 * 15 * The above copyright notice and this permission notice shall be 16 * included in all copies or substantial portions of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 19 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 21 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE 22 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION 23 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 24 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 */ 26 27 var m = require('mraa'); //require mraa 28 29 // helper function to go from hex val to dec 30 function char(x) { return parseInt(x, 16); } 31 32 x = new m.I2c(0) 33 x.address(0x77) 34 35 // initialise device 36 if (x.readReg(char('0xd0')) != char('0x55')) { 37 console.log("error"); 38 } 39 40 // we want to read temperature so write 0x2e into control reg 41 x.writeReg(char('0xf4'), char('0x2e')) 42 43 // read a 16bit reg, obviously it's uncalibrated so mostly a useless value :) 44 console.log(x.readWordReg(char('0xf6'))) 45 46 // and we can do the same thing with the read()/write() calls if we wished 47 // thought I'd really not recommend it! 48 buf = new Buffer(2) 49 buf[0] = char('0xf4') 50 buf[1] = char('0x2e') 51 console.log(buf.toString('hex')) 52 x.write(buf) 53 54 x.writeByte(char('0xf6')) 55 d = x.read(2) 56