Aleksander Vognild Burkow / TxIR

Fork of TxIR

Fork of TxIR by Nordic Pucks

TxIR.cpp@3:bc64c2d5bc26, 2014-07-09 (annotated)

Committer:
aleksanb
Date:
Wed Jul 09 14:46:25 2014 +0000
Revision:
3:bc64c2d5bc26
Parent:
2:cc8371213c85 
A wide plethora of bugfixes and code formatting changes.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ASaidi 0:7d2088337345 1
ASaidi 0:7d2088337345 2 /******************************************************************************
ASaidi 0:7d2088337345 3 * Low level infrared transmission
ASaidi 0:7d2088337345 4 * This library provides a low level interface to send IR commands. in principle
ASaidi 0:7d2088337345 5 * other higher level IR type remotes could be build on top of this. I wrote
ASaidi 0:7d2088337345 6 * this code to send IR commands to a Nikon camera, which it works rather well
aleksanb 3:bc64c2d5bc26 7 * for.
ASaidi 0:7d2088337345 8 *
ASaidi 0:7d2088337345 9 * Copyright (C) 2010 Ali Saidi
aleksanb 3:bc64c2d5bc26 10 *
ASaidi 0:7d2088337345 11 * Permission is hereby granted, free of charge, to any person obtaining a copy
ASaidi 0:7d2088337345 12 * of this software and associated documentation files (the "Software"), to deal
ASaidi 0:7d2088337345 13 * in the Software without restriction, including without limitation the rights
ASaidi 0:7d2088337345 14 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
ASaidi 0:7d2088337345 15 * copies of the Software, and to permit persons to whom the Software is
ASaidi 0:7d2088337345 16 * furnished to do so, subject to the following conditions:
aleksanb 3:bc64c2d5bc26 17 *
ASaidi 0:7d2088337345 18 * The above copyright notice and this permission notice shall be included in
ASaidi 0:7d2088337345 19 * all copies or substantial portions of the Software.
aleksanb 3:bc64c2d5bc26 20 *
ASaidi 0:7d2088337345 21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
ASaidi 0:7d2088337345 22 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
ASaidi 0:7d2088337345 23 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
ASaidi 0:7d2088337345 24 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
ASaidi 0:7d2088337345 25 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
ASaidi 0:7d2088337345 26 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
ASaidi 0:7d2088337345 27 * THE SOFTWARE.
ASaidi 0:7d2088337345 28 */
aleksanb 3:bc64c2d5bc26 29
aleksanb 3:bc64c2d5bc26 30 #include "mbed.h"
aleksanb 3:bc64c2d5bc26 31 #include "TxIR.hpp"
ASaidi 0:7d2088337345 32
aleksanb 3:bc64c2d5bc26 33 Serial pc(USBTX, USBRX);
aleksanb 3:bc64c2d5bc26 34
aleksanb 3:bc64c2d5bc26 35 Timer timer;
ASaidi 0:7d2088337345 36
ASaidi 0:7d2088337345 37 bool
aleksanb 3:bc64c2d5bc26 38 TxIR::txSeq(unsigned freq, unsigned len, const unsigned *data)
ASaidi 0:7d2088337345 39 {
ASaidi 0:7d2088337345 40 // @todo a lock or semaphore should be used here
aleksanb 3:bc64c2d5bc26 41 if (inUse()) {
ASaidi 0:7d2088337345 42 return false;
aleksanb 3:bc64c2d5bc26 43 }
ASaidi 0:7d2088337345 44 _inUse = true;
aleksanb 3:bc64c2d5bc26 45
ASaidi 0:7d2088337345 46 // keep a copy of the data, so it can't change
aleksanb 3:bc64c2d5bc26 47 int pos = 0;
ASaidi 0:7d2088337345 48 // setup the PWM
ASaidi 0:7d2088337345 49 txPin.write(0.0);
ASaidi 0:7d2088337345 50 txPin.period_us(freq);
aleksanb 3:bc64c2d5bc26 51
sigveseb 2:cc8371213c85 52 int times[len];
aleksanb 3:bc64c2d5bc26 53 for (int i=0; i<len; i++) {
aleksanb 3:bc64c2d5bc26 54 times[i] = 0;
sigveseb 2:cc8371213c85 55 }
aleksanb 3:bc64c2d5bc26 56
sigveseb 2:cc8371213c85 57 int bit = 1;
sigveseb 2:cc8371213c85 58 pc.printf("S\n");
ASaidi 0:7d2088337345 59 txPin.write(0.5);
sigveseb 2:cc8371213c85 60 timer.start();
aleksanb 3:bc64c2d5bc26 61
sigveseb 2:cc8371213c85 62 int time = timer.read_us();
sigveseb 2:cc8371213c85 63 int old_time = time;
sigveseb 2:cc8371213c85 64 int dt = 0;
aleksanb 3:bc64c2d5bc26 65
aleksanb 3:bc64c2d5bc26 66 while (pos < len) {
aleksanb 3:bc64c2d5bc26 67 // TODO: Handle timer overflow
aleksanb 3:bc64c2d5bc26 68 // Consider using GPIOTE
sigveseb 2:cc8371213c85 69 old_time = time;
sigveseb 2:cc8371213c85 70 time = timer.read_us();
aleksanb 3:bc64c2d5bc26 71 dt += time - old_time;
aleksanb 3:bc64c2d5bc26 72
aleksanb 3:bc64c2d5bc26 73 while (dt > data[pos] && pos < len) {
sigveseb 2:cc8371213c85 74 dt -= data[pos];
sigveseb 2:cc8371213c85 75 bit = !bit;
sigveseb 2:cc8371213c85 76 txPin.write(0.5 * bit);
sigveseb 2:cc8371213c85 77 times[pos] = dt;
sigveseb 2:cc8371213c85 78 pos++;
sigveseb 2:cc8371213c85 79 }
sigveseb 2:cc8371213c85 80 }
aleksanb 3:bc64c2d5bc26 81
sigveseb 2:cc8371213c85 82 timer.stop();
sigveseb 2:cc8371213c85 83 pc.printf("Success, wrote %i/%i\n", pos, len);
sigveseb 2:cc8371213c85 84 pc.printf("Miss timings: [%i", times[0]);
aleksanb 3:bc64c2d5bc26 85 for (int i=1; i<len; i++) {
sigveseb 2:cc8371213c85 86 pc.printf(", %i", times[i]);
sigveseb 2:cc8371213c85 87 }
aleksanb 3:bc64c2d5bc26 88 pc.printf("]\n");
sigveseb 2:cc8371213c85 89 txPin.write(0);
sigveseb 2:cc8371213c85 90 _inUse = false;
ASaidi 0:7d2088337345 91 return true;
ASaidi 0:7d2088337345 92 }