ENEL400 / L2Frame

Layer 2 Aloha packet

Dependents:   AlohaTransceiver

AlohaFrame.cpp@3:9bc861001717, 2016-08-11 (annotated)

Committer:
rba90
Date:
Thu Aug 11 02:34:23 2016 +0000
Revision:
3:9bc861001717
Parent:
2:849128cfddb8 
move some #define from .c to .h

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rba90 0:bd0c4fdc6833 1 #include "AlohaFrame.h"
rba90 0:bd0c4fdc6833 2 #include "crc.h"
rba90 0:bd0c4fdc6833 3 #include <string.h>
rba90 0:bd0c4fdc6833 4
rba90 0:bd0c4fdc6833 5 #ifdef _DEBUG
rba90 0:bd0c4fdc6833 6 #include <cassert>
rba90 0:bd0c4fdc6833 7 #endif
rba90 0:bd0c4fdc6833 8
rba90 0:bd0c4fdc6833 9 #define CRC_BASE_IDX 3
rba90 0:bd0c4fdc6833 10
rba90 0:bd0c4fdc6833 11 AlohaFrame::AlohaFrame()
rba90 0:bd0c4fdc6833 12 {
rba90 0:bd0c4fdc6833 13 // init variables
rba90 0:bd0c4fdc6833 14 memset(_buffer, 0x0, sizeof(_buffer));
rba90 0:bd0c4fdc6833 15 _isVerified = false;
rba90 0:bd0c4fdc6833 16 }
rba90 0:bd0c4fdc6833 17
rba90 0:bd0c4fdc6833 18 AlohaFrame::AlohaFrame(uint8_t *data, uint8_t sz)
rba90 0:bd0c4fdc6833 19 {
rba90 0:bd0c4fdc6833 20 // the user takes the responsibility of making sure
rba90 0:bd0c4fdc6833 21 // they have sufficient memory for data buffer
rba90 0:bd0c4fdc6833 22
rba90 0:bd0c4fdc6833 23 // copy data to internal buffer
rba90 0:bd0c4fdc6833 24 memcpy(_buffer, data, sz);
rba90 0:bd0c4fdc6833 25
rba90 0:bd0c4fdc6833 26 // set verify flag
rba90 0:bd0c4fdc6833 27 _isVerified = false;
rba90 0:bd0c4fdc6833 28 }
rba90 0:bd0c4fdc6833 29
rba90 0:bd0c4fdc6833 30
rba90 0:bd0c4fdc6833 31 AlohaFrame::~AlohaFrame()
rba90 0:bd0c4fdc6833 32 {
rba90 0:bd0c4fdc6833 33 }
rba90 0:bd0c4fdc6833 34
rba90 0:bd0c4fdc6833 35 void AlohaFrame::generateCrc()
rba90 0:bd0c4fdc6833 36 {
rba90 0:bd0c4fdc6833 37 uint8_t crc_idx = CRC_BASE_IDX + getPayloadLength();
rba90 0:bd0c4fdc6833 38
rba90 0:bd0c4fdc6833 39 _buffer[crc_idx] = crc8(_buffer, crc_idx);
rba90 0:bd0c4fdc6833 40
rba90 0:bd0c4fdc6833 41 // set verify flag
rba90 0:bd0c4fdc6833 42 _isVerified = true;
rba90 0:bd0c4fdc6833 43 }
rba90 0:bd0c4fdc6833 44
rba90 0:bd0c4fdc6833 45 bool AlohaFrame::verify()
rba90 0:bd0c4fdc6833 46 {
rba90 0:bd0c4fdc6833 47 uint8_t crc_idx = CRC_BASE_IDX + getPayloadLength();
rba90 0:bd0c4fdc6833 48
rba90 0:bd0c4fdc6833 49 if (_isVerified)
rba90 0:bd0c4fdc6833 50 {
rba90 0:bd0c4fdc6833 51 return true;
rba90 0:bd0c4fdc6833 52 }
rba90 0:bd0c4fdc6833 53 else
rba90 0:bd0c4fdc6833 54 {
rba90 0:bd0c4fdc6833 55 return _buffer[crc_idx] == crc8(_buffer, crc_idx);
rba90 0:bd0c4fdc6833 56 }
rba90 0:bd0c4fdc6833 57 }
rba90 0:bd0c4fdc6833 58
rba90 0:bd0c4fdc6833 59 uint8_t AlohaFrame::serialize(uint8_t *buffer)
rba90 0:bd0c4fdc6833 60 {
rba90 0:bd0c4fdc6833 61 uint8_t total_length = FIXED_BYTE + getPayloadLength();
rba90 0:bd0c4fdc6833 62
rba90 0:bd0c4fdc6833 63 memcpy(buffer, _buffer, total_length);
rba90 0:bd0c4fdc6833 64
rba90 0:bd0c4fdc6833 65 return total_length;
rba90 0:bd0c4fdc6833 66 }
rba90 0:bd0c4fdc6833 67
rba90 0:bd0c4fdc6833 68 void AlohaFrame::setType(uint8_t type)
rba90 0:bd0c4fdc6833 69 {
rba90 0:bd0c4fdc6833 70 // clear upper 4 bits
rba90 0:bd0c4fdc6833 71 _buffer[0] &= 0x0f;
rba90 0:bd0c4fdc6833 72
rba90 0:bd0c4fdc6833 73 // set bits
rba90 0:bd0c4fdc6833 74 _buffer[0] |= type << 4;
rba90 0:bd0c4fdc6833 75
rba90 0:bd0c4fdc6833 76 // set verify flag
rba90 0:bd0c4fdc6833 77 _isVerified = false;
rba90 0:bd0c4fdc6833 78 }
rba90 0:bd0c4fdc6833 79
rba90 0:bd0c4fdc6833 80 void AlohaFrame::setPayloadLength(uint8_t length)
rba90 0:bd0c4fdc6833 81 {
rba90 0:bd0c4fdc6833 82 // clear lower 4 bits
rba90 0:bd0c4fdc6833 83 _buffer[0] &= 0xf0;
rba90 0:bd0c4fdc6833 84
rba90 0:bd0c4fdc6833 85 // set bits
rba90 0:bd0c4fdc6833 86 _buffer[0] |= length & 0x0f;
rba90 0:bd0c4fdc6833 87
rba90 0:bd0c4fdc6833 88 // set verify flag
rba90 0:bd0c4fdc6833 89 _isVerified = false;
rba90 0:bd0c4fdc6833 90 }
rba90 0:bd0c4fdc6833 91
rba90 0:bd0c4fdc6833 92 void AlohaFrame::setSourceAddress(uint8_t sa)
rba90 0:bd0c4fdc6833 93 {
rba90 0:bd0c4fdc6833 94 // clear upper 4 bits
rba90 0:bd0c4fdc6833 95 _buffer[1] &= 0x0f;
rba90 0:bd0c4fdc6833 96
rba90 0:bd0c4fdc6833 97 // set bits
rba90 0:bd0c4fdc6833 98 _buffer[1] |= sa << 4;
rba90 0:bd0c4fdc6833 99
rba90 0:bd0c4fdc6833 100 // set verify flag
rba90 0:bd0c4fdc6833 101 _isVerified = false;
rba90 0:bd0c4fdc6833 102 }
rba90 0:bd0c4fdc6833 103
rba90 0:bd0c4fdc6833 104 void AlohaFrame::setDestinationAddress(uint8_t da)
rba90 0:bd0c4fdc6833 105 {
rba90 0:bd0c4fdc6833 106 // clear lower 4 bits
rba90 0:bd0c4fdc6833 107 _buffer[1] &= 0xf0;
rba90 0:bd0c4fdc6833 108
rba90 0:bd0c4fdc6833 109 // set bits
rba90 0:bd0c4fdc6833 110 _buffer[1] |= da & 0x0f;
rba90 0:bd0c4fdc6833 111
rba90 0:bd0c4fdc6833 112 // set verify flag
rba90 0:bd0c4fdc6833 113 _isVerified = false;
rba90 0:bd0c4fdc6833 114 }
rba90 0:bd0c4fdc6833 115
rba90 0:bd0c4fdc6833 116 void AlohaFrame::setFullMessageFlag(uint8_t fmf)
rba90 0:bd0c4fdc6833 117 {
rba90 0:bd0c4fdc6833 118 // clear upper 1 bits
rba90 0:bd0c4fdc6833 119 _buffer[2] &= 0x7f;
rba90 0:bd0c4fdc6833 120
rba90 0:bd0c4fdc6833 121 // set bits
rba90 0:bd0c4fdc6833 122 _buffer[2] |= fmf << 7;
rba90 0:bd0c4fdc6833 123
rba90 0:bd0c4fdc6833 124 // set verify flag
rba90 0:bd0c4fdc6833 125 _isVerified = false;
rba90 0:bd0c4fdc6833 126 }
rba90 0:bd0c4fdc6833 127
rba90 0:bd0c4fdc6833 128 void AlohaFrame::setSequenceID(uint8_t seqid)
rba90 0:bd0c4fdc6833 129 {
rba90 0:bd0c4fdc6833 130 // clear lower 7 bits
rba90 0:bd0c4fdc6833 131 _buffer[2] &= 0x80;
rba90 0:bd0c4fdc6833 132
rba90 0:bd0c4fdc6833 133 // set bits
rba90 0:bd0c4fdc6833 134 _buffer[2] |= seqid & 0x7f;
rba90 0:bd0c4fdc6833 135
rba90 0:bd0c4fdc6833 136 // set verify flag
rba90 0:bd0c4fdc6833 137 _isVerified = false;
rba90 0:bd0c4fdc6833 138 }
rba90 0:bd0c4fdc6833 139
rba90 2:849128cfddb8 140 void AlohaFrame::setPayload(uint8_t idx, uint8_t payload)
rba90 0:bd0c4fdc6833 141 {
rba90 0:bd0c4fdc6833 142 // set payload based on index
rba90 0:bd0c4fdc6833 143 _buffer[CRC_BASE_IDX + idx] = payload;
rba90 0:bd0c4fdc6833 144
rba90 0:bd0c4fdc6833 145 // set verify flag
rba90 0:bd0c4fdc6833 146 _isVerified = false;
rba90 0:bd0c4fdc6833 147 }
rba90 0:bd0c4fdc6833 148
rba90 0:bd0c4fdc6833 149 uint8_t AlohaFrame::getType()
rba90 0:bd0c4fdc6833 150 {
rba90 0:bd0c4fdc6833 151 return (_buffer[0] & 0xf0) >> 4;
rba90 0:bd0c4fdc6833 152 }
rba90 0:bd0c4fdc6833 153
rba90 0:bd0c4fdc6833 154 uint8_t AlohaFrame::getPayloadLength()
rba90 0:bd0c4fdc6833 155 {
rba90 0:bd0c4fdc6833 156 return _buffer[0] & 0x0f;
rba90 0:bd0c4fdc6833 157 }
rba90 0:bd0c4fdc6833 158
rba90 0:bd0c4fdc6833 159 uint8_t AlohaFrame::getSourceAddress()
rba90 0:bd0c4fdc6833 160 {
rba90 0:bd0c4fdc6833 161 return (_buffer[1] & 0xf0) >> 4;
rba90 0:bd0c4fdc6833 162 }
rba90 0:bd0c4fdc6833 163
rba90 0:bd0c4fdc6833 164 uint8_t AlohaFrame::getDestinationAddress()
rba90 0:bd0c4fdc6833 165 {
rba90 0:bd0c4fdc6833 166 return _buffer[1] & 0x0f;
rba90 0:bd0c4fdc6833 167 }
rba90 0:bd0c4fdc6833 168
rba90 0:bd0c4fdc6833 169 uint8_t AlohaFrame::getFullMessageFlag()
rba90 0:bd0c4fdc6833 170 {
rba90 0:bd0c4fdc6833 171 return (_buffer[2] & 0x80) >> 7;
rba90 0:bd0c4fdc6833 172 }
rba90 0:bd0c4fdc6833 173
rba90 0:bd0c4fdc6833 174 uint8_t AlohaFrame::getSequenceID()
rba90 0:bd0c4fdc6833 175 {
rba90 0:bd0c4fdc6833 176 return _buffer[2] & 0x7f;
rba90 0:bd0c4fdc6833 177 }
rba90 0:bd0c4fdc6833 178
rba90 0:bd0c4fdc6833 179 uint8_t AlohaFrame::getPayload(uint8_t idx)
rba90 0:bd0c4fdc6833 180 {
rba90 0:bd0c4fdc6833 181 return _buffer[CRC_BASE_IDX + idx];
rba90 0:bd0c4fdc6833 182 }
rba90 0:bd0c4fdc6833 183
rba90 0:bd0c4fdc6833 184 uint8_t AlohaFrame::getCrc()
rba90 0:bd0c4fdc6833 185 {
rba90 0:bd0c4fdc6833 186 uint8_t crc_idx = CRC_BASE_IDX + getPayloadLength();
rba90 0:bd0c4fdc6833 187
rba90 0:bd0c4fdc6833 188 if (_isVerified)
rba90 0:bd0c4fdc6833 189 {
rba90 0:bd0c4fdc6833 190 return _buffer[crc_idx];
rba90 0:bd0c4fdc6833 191 }
rba90 0:bd0c4fdc6833 192 else
rba90 0:bd0c4fdc6833 193 {
rba90 0:bd0c4fdc6833 194 return crc8(_buffer, crc_idx);
rba90 0:bd0c4fdc6833 195 }
rba90 0:bd0c4fdc6833 196 }
rba90 0:bd0c4fdc6833 197
rba90 0:bd0c4fdc6833 198 #ifdef _DEBUG
rba90 0:bd0c4fdc6833 199 void AlohaFrame::unit_test()
rba90 0:bd0c4fdc6833 200 {
rba90 0:bd0c4fdc6833 201 // value test
rba90 0:bd0c4fdc6833 202 AlohaFrame testObject;
rba90 0:bd0c4fdc6833 203
rba90 0:bd0c4fdc6833 204 testObject.setType(0x0);
rba90 0:bd0c4fdc6833 205 testObject.setPayloadLength(0x3);
rba90 0:bd0c4fdc6833 206 testObject.setSourceAddress(0x2);
rba90 0:bd0c4fdc6833 207 testObject.setDestinationAddress(0x3);
rba90 0:bd0c4fdc6833 208 testObject.setFullMessageFlag(0x1);
rba90 0:bd0c4fdc6833 209 testObject.setSequenceID(0x4);
rba90 0:bd0c4fdc6833 210 testObject.setPayload(0x56, 0);
rba90 0:bd0c4fdc6833 211 testObject.setPayload(0x67, 1);
rba90 0:bd0c4fdc6833 212 testObject.setPayload(0x89, 2);
rba90 0:bd0c4fdc6833 213
rba90 0:bd0c4fdc6833 214 assert(0x0 == testObject.getType());
rba90 0:bd0c4fdc6833 215 assert(0x3 == testObject.getPayloadLength());
rba90 0:bd0c4fdc6833 216 assert(0x2 == testObject.getSourceAddress());
rba90 0:bd0c4fdc6833 217 assert(0x3 == testObject.getDestinationAddress());
rba90 0:bd0c4fdc6833 218 assert(0x1 == testObject.getFullMessageFlag());
rba90 0:bd0c4fdc6833 219 assert(0x4 == testObject.getSequenceID());
rba90 0:bd0c4fdc6833 220 assert(0x56 == testObject.getPayload(0));
rba90 0:bd0c4fdc6833 221 assert(0x67 == testObject.getPayload(1));
rba90 0:bd0c4fdc6833 222 assert(0x89 == testObject.getPayload(2));
rba90 0:bd0c4fdc6833 223
rba90 0:bd0c4fdc6833 224 assert(false == testObject.verify());
rba90 0:bd0c4fdc6833 225 testObject.generateCrc();
rba90 0:bd0c4fdc6833 226 assert(true == testObject.verify());
rba90 0:bd0c4fdc6833 227 assert(0xa1 == testObject.getCrc());
rba90 0:bd0c4fdc6833 228
rba90 0:bd0c4fdc6833 229 // value test round 2
rba90 0:bd0c4fdc6833 230 uint8_t testString[] = { 0x03, 0x23, 0x84, 0x56, 0x67, 0x89, 0xa1 };
rba90 0:bd0c4fdc6833 231 AlohaFrame testObject2(testString, 7);
rba90 0:bd0c4fdc6833 232
rba90 0:bd0c4fdc6833 233 assert(0x0 == testObject2.getType());
rba90 0:bd0c4fdc6833 234 assert(0x3 == testObject2.getPayloadLength());
rba90 0:bd0c4fdc6833 235 assert(0x2 == testObject2.getSourceAddress());
rba90 0:bd0c4fdc6833 236 assert(0x3 == testObject2.getDestinationAddress());
rba90 0:bd0c4fdc6833 237 assert(0x1 == testObject2.getFullMessageFlag());
rba90 0:bd0c4fdc6833 238 assert(0x4 == testObject2.getSequenceID());
rba90 0:bd0c4fdc6833 239 assert(0x56 == testObject2.getPayload(0));
rba90 0:bd0c4fdc6833 240 assert(0x67 == testObject2.getPayload(1));
rba90 0:bd0c4fdc6833 241 assert(0x89 == testObject2.getPayload(2));
rba90 0:bd0c4fdc6833 242
rba90 0:bd0c4fdc6833 243 assert(true == testObject2.verify());
rba90 0:bd0c4fdc6833 244 testObject2.generateCrc();
rba90 0:bd0c4fdc6833 245 assert(true == testObject2.verify());
rba90 0:bd0c4fdc6833 246 assert(0xa1 == testObject2.getCrc());
rba90 0:bd0c4fdc6833 247 }
rba90 0:bd0c4fdc6833 248 #endif