Arkadi Rafalovich / Mbed 2 deprecated Serial_Packet_Example

Serial Packet Handler

Dependencies:   MbedJSONValue mbed

main.cpp@0:6080c5029b3f, 2018-01-15 (annotated)

Committer:
Arkadi
Date:
Mon Jan 15 10:40:06 2018 +0000
Revision:
0:6080c5029b3f
Child:
1:711a27baa42d
Serial Packet Handler

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Arkadi 0:6080c5029b3f 1 ////////////////////////////////////////
Arkadi 0:6080c5029b3f 2 // Serial Packet - picojson //
Arkadi 0:6080c5029b3f 3 // Arkadiraf@gmail.com - 05/06/2017 //
Arkadi 0:6080c5029b3f 4 ////////////////////////////////////////
Arkadi 0:6080c5029b3f 5 /*
Arkadi 0:6080c5029b3f 6 Construct packet from uart and parse with json format
Arkadi 0:6080c5029b3f 7 json:<PACKET>\r\n
Arkadi 0:6080c5029b3f 8 */
Arkadi 0:6080c5029b3f 9
Arkadi 0:6080c5029b3f 10 /*
Arkadi 0:6080c5029b3f 11 Board : Nucleo STM32F446RE
Arkadi 0:6080c5029b3f 12 */
Arkadi 0:6080c5029b3f 13
Arkadi 0:6080c5029b3f 14 /*
Arkadi 0:6080c5029b3f 15 Pinout:
Arkadi 0:6080c5029b3f 16 PC - Serial 2
Arkadi 0:6080c5029b3f 17 PA_2 (Tx) --> STLINK
Arkadi 0:6080c5029b3f 18 PA_3 (Rx) --> STLINK
Arkadi 0:6080c5029b3f 19 */
Arkadi 0:6080c5029b3f 20
Arkadi 0:6080c5029b3f 21 ///////////////
Arkadi 0:6080c5029b3f 22 // Libraries //
Arkadi 0:6080c5029b3f 23 ///////////////
Arkadi 0:6080c5029b3f 24 #include "mbed.h"
Arkadi 0:6080c5029b3f 25 #include "picojson.h"
Arkadi 0:6080c5029b3f 26 //#include "BufferedSerial.h" // uart handler library
Arkadi 0:6080c5029b3f 27 ///////////////
Arkadi 0:6080c5029b3f 28 // #defines //
Arkadi 0:6080c5029b3f 29 ///////////////
Arkadi 0:6080c5029b3f 30
Arkadi 0:6080c5029b3f 31 #define DEBUG_MOD1
Arkadi 0:6080c5029b3f 32 #define MSG_BUFFER_SIZE 512
Arkadi 0:6080c5029b3f 33 #define HEADER_SIZE 5
Arkadi 0:6080c5029b3f 34 #define FOOTER_SIZE 2
Arkadi 0:6080c5029b3f 35
Arkadi 0:6080c5029b3f 36 /////////////
Arkadi 0:6080c5029b3f 37 // Objects //
Arkadi 0:6080c5029b3f 38 /////////////
Arkadi 0:6080c5029b3f 39
Arkadi 0:6080c5029b3f 40 // uart
Arkadi 0:6080c5029b3f 41 Serial pc(USBTX, USBRX);
Arkadi 0:6080c5029b3f 42
Arkadi 0:6080c5029b3f 43 // digital output
Arkadi 0:6080c5029b3f 44 DigitalOut led(PA_5);
Arkadi 0:6080c5029b3f 45 ///////////////
Arkadi 0:6080c5029b3f 46 // variables //
Arkadi 0:6080c5029b3f 47 ///////////////
Arkadi 0:6080c5029b3f 48
Arkadi 0:6080c5029b3f 49 // json buffer
Arkadi 0:6080c5029b3f 50 char json[MSG_BUFFER_SIZE];
Arkadi 0:6080c5029b3f 51
Arkadi 0:6080c5029b3f 52 // packet variables
Arkadi 0:6080c5029b3f 53 struct packetMSG_struct {
Arkadi 0:6080c5029b3f 54 // recieve message variables
Arkadi 0:6080c5029b3f 55 uint8_t header[HEADER_SIZE];
Arkadi 0:6080c5029b3f 56 uint8_t footer[FOOTER_SIZE];
Arkadi 0:6080c5029b3f 57 uint8_t syncIndex; // sync index for header / footer
Arkadi 0:6080c5029b3f 58 uint8_t syncFlag; // 0 - waiting for header, 1 - waiting for footer, 2 - verify footer, 3 - finish footer send to parser, flash buffer
Arkadi 0:6080c5029b3f 59 // buffer
Arkadi 0:6080c5029b3f 60 uint16_t bufferIndex; // buffer index
Arkadi 0:6080c5029b3f 61 uint8_t buffer[MSG_BUFFER_SIZE];
Arkadi 0:6080c5029b3f 62 } ;
Arkadi 0:6080c5029b3f 63 packetMSG_struct packetMSG;
Arkadi 0:6080c5029b3f 64 ///////////////
Arkadi 0:6080c5029b3f 65 // Functions //
Arkadi 0:6080c5029b3f 66 ///////////////
Arkadi 0:6080c5029b3f 67
Arkadi 0:6080c5029b3f 68 // Serial Event function
Arkadi 0:6080c5029b3f 69 void rxCallback(void);
Arkadi 0:6080c5029b3f 70
Arkadi 0:6080c5029b3f 71 // initialize packet struct
Arkadi 0:6080c5029b3f 72 void initPacket(void);
Arkadi 0:6080c5029b3f 73 ////////////////////////
Arkadi 0:6080c5029b3f 74 // Main Code Setup : //
Arkadi 0:6080c5029b3f 75 ////////////////////////
Arkadi 0:6080c5029b3f 76 int main()
Arkadi 0:6080c5029b3f 77 {
Arkadi 0:6080c5029b3f 78 // init packet:
Arkadi 0:6080c5029b3f 79 initPacket();
Arkadi 0:6080c5029b3f 80 // init uart
Arkadi 0:6080c5029b3f 81 pc.baud(57600);
Arkadi 0:6080c5029b3f 82 // attach serial event interrupt
Arkadi 0:6080c5029b3f 83 pc.attach(&rxCallback, Serial::RxIrq);
Arkadi 0:6080c5029b3f 84
Arkadi 0:6080c5029b3f 85 #ifdef DEBUG_MOD1
Arkadi 0:6080c5029b3f 86 pc.printf("UART Test \r\n");
Arkadi 0:6080c5029b3f 87 #endif
Arkadi 0:6080c5029b3f 88 ///////////////////////
Arkadi 0:6080c5029b3f 89 // Main Code Loop : //
Arkadi 0:6080c5029b3f 90 ///////////////////////
Arkadi 0:6080c5029b3f 91 while(1) {
Arkadi 0:6080c5029b3f 92 //sleep();
Arkadi 0:6080c5029b3f 93 }// end main loop
Arkadi 0:6080c5029b3f 94 }// end main
Arkadi 0:6080c5029b3f 95 ///////////////
Arkadi 0:6080c5029b3f 96 // Functions //
Arkadi 0:6080c5029b3f 97 ///////////////
Arkadi 0:6080c5029b3f 98
Arkadi 0:6080c5029b3f 99 // Serial Event function
Arkadi 0:6080c5029b3f 100 void rxCallback(void)
Arkadi 0:6080c5029b3f 101 {
Arkadi 0:6080c5029b3f 102 while (pc.readable()) {
Arkadi 0:6080c5029b3f 103 // read icoming
Arkadi 0:6080c5029b3f 104 led = !led;
Arkadi 0:6080c5029b3f 105 uint8_t in_byte = pc.getc();
Arkadi 0:6080c5029b3f 106 #ifdef DEBUG_MOD1
Arkadi 0:6080c5029b3f 107 pc.putc(in_byte);
Arkadi 0:6080c5029b3f 108 #endif
Arkadi 0:6080c5029b3f 109 // detect start message , end message
Arkadi 0:6080c5029b3f 110 switch (packetMSG.syncFlag) {
Arkadi 0:6080c5029b3f 111 // waiting for header
Arkadi 0:6080c5029b3f 112 case 0: {
Arkadi 0:6080c5029b3f 113 if (packetMSG.header[packetMSG.syncIndex] == in_byte) {
Arkadi 0:6080c5029b3f 114 packetMSG.syncIndex++;
Arkadi 0:6080c5029b3f 115 if (packetMSG.syncIndex == HEADER_SIZE) { // finish header SYNC
Arkadi 0:6080c5029b3f 116 packetMSG.syncFlag = 1; // start collecting data, wait for footer
Arkadi 0:6080c5029b3f 117 packetMSG.bufferIndex = 0;
Arkadi 0:6080c5029b3f 118 packetMSG.syncIndex=0;
Arkadi 0:6080c5029b3f 119 }
Arkadi 0:6080c5029b3f 120 } else { // reinit sync
Arkadi 0:6080c5029b3f 121 packetMSG.syncIndex=0;
Arkadi 0:6080c5029b3f 122 }
Arkadi 0:6080c5029b3f 123 //pc.printf("case 0 , %d \r\n",packetMSG.syncIndex);
Arkadi 0:6080c5029b3f 124 break;
Arkadi 0:6080c5029b3f 125
Arkadi 0:6080c5029b3f 126 } // waiting for header
Arkadi 0:6080c5029b3f 127
Arkadi 0:6080c5029b3f 128 // waiting for footer
Arkadi 0:6080c5029b3f 129 case 1: {
Arkadi 0:6080c5029b3f 130 // add byte to buffer
Arkadi 0:6080c5029b3f 131 packetMSG.buffer[packetMSG.bufferIndex] = in_byte;
Arkadi 0:6080c5029b3f 132 packetMSG.bufferIndex++;
Arkadi 0:6080c5029b3f 133 if (packetMSG.bufferIndex >= MSG_BUFFER_SIZE) { // buffer overflow
Arkadi 0:6080c5029b3f 134 // reset buffer
Arkadi 0:6080c5029b3f 135 packetMSG.bufferIndex = 0;
Arkadi 0:6080c5029b3f 136 packetMSG.syncIndex = 0;
Arkadi 0:6080c5029b3f 137 packetMSG.syncFlag = 0;
Arkadi 0:6080c5029b3f 138 } else if (packetMSG.footer[packetMSG.syncIndex] == in_byte) { // footer char recieved
Arkadi 0:6080c5029b3f 139 packetMSG.syncIndex++;
Arkadi 0:6080c5029b3f 140 packetMSG.syncFlag=2; // move to verify footer
Arkadi 0:6080c5029b3f 141 }
Arkadi 0:6080c5029b3f 142 //pc.printf("case 2 , %d \r\n",packetMSG.syncIndex);
Arkadi 0:6080c5029b3f 143 break;
Arkadi 0:6080c5029b3f 144 } // waiting for footer
Arkadi 0:6080c5029b3f 145
Arkadi 0:6080c5029b3f 146 // verify footer
Arkadi 0:6080c5029b3f 147 case 2: {
Arkadi 0:6080c5029b3f 148 // add byte to buffer
Arkadi 0:6080c5029b3f 149 packetMSG.buffer[packetMSG.bufferIndex] = in_byte;
Arkadi 0:6080c5029b3f 150 packetMSG.bufferIndex++;
Arkadi 0:6080c5029b3f 151 if (packetMSG.bufferIndex >= MSG_BUFFER_SIZE) { // buffer overflow
Arkadi 0:6080c5029b3f 152 // reset buffer
Arkadi 0:6080c5029b3f 153 packetMSG.bufferIndex = 0;
Arkadi 0:6080c5029b3f 154 packetMSG.syncIndex = 0;
Arkadi 0:6080c5029b3f 155 packetMSG.syncFlag = 0;
Arkadi 0:6080c5029b3f 156 } else if (packetMSG.footer[packetMSG.syncIndex] == in_byte) { // footer char recieved
Arkadi 0:6080c5029b3f 157 packetMSG.syncIndex++;
Arkadi 0:6080c5029b3f 158 if (packetMSG.syncIndex == FOOTER_SIZE) { // finish footer SYNC
Arkadi 0:6080c5029b3f 159 packetMSG.syncFlag = 3;
Arkadi 0:6080c5029b3f 160
Arkadi 0:6080c5029b3f 161 // copy packet to json buffer - failed attempt
Arkadi 0:6080c5029b3f 162 //char *json = (char*) malloc(packetMSG.bufferIndex+1);
Arkadi 0:6080c5029b3f 163 memcpy (&json, &packetMSG.buffer, packetMSG.bufferIndex);
Arkadi 0:6080c5029b3f 164 json[packetMSG.bufferIndex]=NULL; // end NULL to indicate end of string
Arkadi 0:6080c5029b3f 165
Arkadi 0:6080c5029b3f 166 // copy packet to json buffer with sprintf
Arkadi 0:6080c5029b3f 167 //sprintf(json, "%.*s", packetMSG.bufferIndex, packetMSG.buffer );
Arkadi 0:6080c5029b3f 168
Arkadi 0:6080c5029b3f 169 // send msg to parse.
Arkadi 0:6080c5029b3f 170 pc.printf("%d, %.*s", packetMSG.bufferIndex ,packetMSG.bufferIndex, packetMSG.buffer );
Arkadi 0:6080c5029b3f 171 pc.printf("%d, %s", sizeof(json), json);
Arkadi 0:6080c5029b3f 172 //free(json);
Arkadi 0:6080c5029b3f 173 // reset buffer
Arkadi 0:6080c5029b3f 174 packetMSG.bufferIndex = 0;
Arkadi 0:6080c5029b3f 175 packetMSG.syncIndex = 0;
Arkadi 0:6080c5029b3f 176 packetMSG.syncFlag = 0;
Arkadi 0:6080c5029b3f 177 }
Arkadi 0:6080c5029b3f 178 } else { // footer broke restart wait for footer
Arkadi 0:6080c5029b3f 179 packetMSG.syncFlag=1;
Arkadi 0:6080c5029b3f 180 // verify that it didnt broke on first footer char
Arkadi 0:6080c5029b3f 181 if (packetMSG.footer[0] == in_byte) {
Arkadi 0:6080c5029b3f 182 packetMSG.syncIndex=1;
Arkadi 0:6080c5029b3f 183 } else {
Arkadi 0:6080c5029b3f 184 packetMSG.syncIndex=0;
Arkadi 0:6080c5029b3f 185 }
Arkadi 0:6080c5029b3f 186 }
Arkadi 0:6080c5029b3f 187 break;
Arkadi 0:6080c5029b3f 188
Arkadi 0:6080c5029b3f 189 } // verify footer
Arkadi 0:6080c5029b3f 190 default: {
Arkadi 0:6080c5029b3f 191 pc.printf("Sonmething went wrong \r\n");
Arkadi 0:6080c5029b3f 192 break;
Arkadi 0:6080c5029b3f 193 }
Arkadi 0:6080c5029b3f 194 } // end switch
Arkadi 0:6080c5029b3f 195 }// end uart readable
Arkadi 0:6080c5029b3f 196 } // end rxCallback
Arkadi 0:6080c5029b3f 197
Arkadi 0:6080c5029b3f 198
Arkadi 0:6080c5029b3f 199 // initialize packet struct
Arkadi 0:6080c5029b3f 200 void initPacket(void)
Arkadi 0:6080c5029b3f 201 {
Arkadi 0:6080c5029b3f 202 // init variables to default:
Arkadi 0:6080c5029b3f 203 packetMSG.header[0] = 'j';
Arkadi 0:6080c5029b3f 204 packetMSG.header[1] = 's';
Arkadi 0:6080c5029b3f 205 packetMSG.header[2] = 'o';
Arkadi 0:6080c5029b3f 206 packetMSG.header[3] = 'n';
Arkadi 0:6080c5029b3f 207 packetMSG.header[4] = ':';
Arkadi 0:6080c5029b3f 208
Arkadi 0:6080c5029b3f 209 packetMSG.footer[0]= 13; // /r
Arkadi 0:6080c5029b3f 210 packetMSG.footer[1]= 10; // /n
Arkadi 0:6080c5029b3f 211
Arkadi 0:6080c5029b3f 212 packetMSG.syncIndex=0; // sync index for header / footer
Arkadi 0:6080c5029b3f 213 packetMSG.syncFlag=0; // 0 - waiting for header, 1 - waiting for footer, 2 - verify footer, 3 - finish footer send to parser, flash buffer
Arkadi 0:6080c5029b3f 214 packetMSG.bufferIndex=0; // buffer index
Arkadi 0:6080c5029b3f 215 }