Javascript  |  60行  |  2.12 KB

/*jslint node:true, vars:true, bitwise:true, unparam:true */
/*jshint unused:true */

/*
 * Author: Jon Trulson <jtrulson@ics.com>
 * Copyright (c) 2015 Intel Corporation.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */


var nfcTagObj = require('jsupm_m24lr64e');

// Instantiate a M24LR64E Grove NFC Tag Module on UART 0
var nfcTag = new nfcTagObj.M24LR64E(nfcTagObj.M24LR64E_I2C_BUS);

// This example accesses the device in the 'user' (default) mode,
// reads the last byte of data in the EEPROM, inverts it, writes
// it back, and then re-reads it.

// Read the last byte of the EEPROM area
var addr = (nfcTagObj.M24LR64E.EEPROM_I2C_LENGTH - 1);
console.log("Address: " + addr);
var byte = nfcTag.readByte(addr);

console.log("Read byte: " + byte.toString(16));

// Now change it to it's opposite and write it
byte = (~byte & 0xff);
nfcTag.writeByte(addr, byte);
console.log("Wrote inverted byte: " + byte.toString(16));

// Now read it back.
byte = nfcTag.readByte(addr);
console.log("Read byte: " + byte.toString(16));

// clean up
nfcTag = null;
nfcTagObj.cleanUp();
nfcTagObj = null;
console.log("Exiting...");
process.exit(0);