radio/src/pulses/pxx1.h

   1 /*
   2  * Copyright (C) OpenTX
   3  *
   4  * Based on code named
   5  *   th9x - http://code.google.com/p/th9x
   6  *   er9x - http://code.google.com/p/er9x
   7  *   gruvin9x - http://code.google.com/p/gruvin9x
   8  *
   9  * License GPLv2: http://www.gnu.org/licenses/gpl-2.0.html
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  */
  20
  21 #ifndef _PULSES_PXX1_H_
  22 #define _PULSES_PXX1_H_
  23
  24 #include "pxx.h"
  25 #include "crc.h"
  26
  27 struct HeartbeatCapture {
  28   uint32_t timestamp;
  29   uint32_t count;
  30   uint8_t valid;
  31 };
  32
  33 extern volatile HeartbeatCapture heartbeatCapture;
  34
  35 class Pxx1CrcMixin {
  36   protected:
  37     void initCrc()
  38     {
  39       crc = 0;
  40     }
  41
  42     void addToCrc(uint8_t byte)
  43     {
  44       crc = (crc << 8) ^ (crc16tab_1189[((crc >> 8) ^ byte) & 0xFF]);
  45     }
  46
  47     uint16_t crc;
  48     static const uint16_t CRCTable[];
  49 };
  50
  51 template <class BitTransport>
  52 class StandardPxx1Transport: public BitTransport, public Pxx1CrcMixin {
  53   protected:
  54     uint8_t ones_count;
  55
  56     void initFrame(uint32_t period)
  57     {
  58       BitTransport::initFrame(period);
  59       ones_count = 0;
  60     }
  61
  62     void addByte(uint8_t byte)
  63     {
  64       Pxx1CrcMixin::addToCrc(byte);
  65       addByteWithoutCrc(byte);
  66     };
  67
  68     void addRawByte(uint8_t byte)
  69     {
  70       for (uint8_t i = 0; i < 8; i++) {
  71         if (byte & 0x80)
  72           BitTransport::addPart(1);
  73         else
  74           BitTransport::addPart(0);
  75         byte <<= 1;
  76       }
  77     }
  78
  79     void addByteWithoutCrc(uint8_t byte)
  80     {
  81       for (uint8_t i = 0; i < 8; i++) {
  82         addBit(byte & 0x80);
  83         byte <<= 1;
  84       }
  85     }
  86
  87     void addBit(uint8_t bit)
  88     {
  89       if (bit) {
  90         BitTransport::addPart(1);
  91         if (++ones_count == 5) {
  92           ones_count = 0;
  93           BitTransport::addPart(0); // Stuff a 0 bit in
  94         }
  95       }
  96       else {
  97         BitTransport::addPart(0);
  98         ones_count = 0;
  99       }
 100     }
 101 };
 102
 103 class UartPxx1Transport: public DataBuffer<uint8_t, 64>, public Pxx1CrcMixin {
 104   protected:
 105     void initFrame(uint32_t period)
 106     {
 107       initBuffer();
 108     }
 109
 110     void addByte(uint8_t byte)
 111     {
 112       Pxx1CrcMixin::addToCrc(byte);
 113       addWithByteStuffing(byte);
 114     }
 115
 116     void addRawByte(uint8_t byte)
 117     {
 118       *ptr++ = byte;
 119     }
 120
 121     void addByteWithoutCrc(uint8_t byte)
 122     {
 123       addWithByteStuffing(byte);
 124     }
 125
 126     void addWithByteStuffing(uint8_t byte)
 127     {
 128       if (0x7E == byte) {
 129         addRawByte(0x7D);
 130         addRawByte(0x5E);
 131       }
 132       else if (0x7D == byte) {
 133         addRawByte(0x7D);
 134         addRawByte(0x5D);
 135       }
 136       else {
 137         addRawByte(byte);
 138       }
 139     }
 140
 141     void addTail()
 142     {
 143       // nothing
 144     }
 145 };
 146
 147 template <class PxxTransport>
 148 class Pxx1Pulses: public PxxTransport
 149 {
 150   public:
 151     void setupFrame(uint8_t port);
 152
 153   protected:
 154     void addHead()
 155     {
 156       // send 7E, do not CRC
 157       PxxTransport::addRawByte(0x7E);
 158     }
 159
 160     void addCrc()
 161     {
 162       PxxTransport::addByteWithoutCrc(Pxx1CrcMixin::crc >> 8);
 163       PxxTransport::addByteWithoutCrc(Pxx1CrcMixin::crc);
 164     }
 165
 166     void addFlag1(uint8_t port, uint8_t sendFailsafe);
 167     void addExtraFlags(uint8_t port);
 168     void addChannels(uint8_t port, uint8_t sendFailsafe, uint8_t sendUpperChannels);
 169     void add8ChannelsFrame(uint8_t port, uint8_t sendUpperChannels, uint8_t sendFailsafe);
 170 };
 171
 172 typedef Pxx1Pulses<UartPxx1Transport> UartPxx1Pulses;
 173 typedef Pxx1Pulses<StandardPxx1Transport<PwmPxxBitTransport>> PwmPxx1Pulses;
 174 typedef Pxx1Pulses<StandardPxx1Transport<SerialPxxBitTransport>> SerialPxx1Pulses;
 175
 176 #endif