ADVES / CANnucleo_Hello

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Dependencies:   CANnucleo

main.cpp@31:0b5c9a37a5a6, 2019-09-13 (annotated)

Committer:
adv_lut
Date:
Fri Sep 13 11:40:20 2019 +0000
Revision:
31:0b5c9a37a5a6
Parent:
29:9ae558ec888c 
CAN nucleo example

Who changed what in which revision?

UserRevisionLine numberNew contents of line
hudakz 0:c5e5d0df6f2a 1 /*
hudakz 16:a86f339d1c25 2 * An example showing how to use the CANnucleo library:
hudakz 0:c5e5d0df6f2a 3 *
hudakz 20:eb1a8042605e 4 * Two affordable (less than $3 on ebay) STM32F103C8T6 boards (20kB SRAM, 64kB Flash),
hudakz 20:eb1a8042605e 5 * (see [https://developer.mbed.org/users/hudakz/code/STM32F103C8T6_Hello/] for more details)
hudakz 6:7ff95ce72f6d 6 * are connected to the same CAN bus via transceivers (MCP2551 or TJA1040, or etc.).
hudakz 6:7ff95ce72f6d 7 * CAN transceivers are not part of NUCLEO boards, therefore must be added by you.
hudakz 6:7ff95ce72f6d 8 * Remember also that CAN bus (even a short one) must be terminated with 120 Ohm resitors at both ends.
hudakz 6:7ff95ce72f6d 9 *
hudakz 16:a86f339d1c25 10 * For more details see the wiki page <https://developer.mbed.org/users/hudakz/code/CANnucleo_Hello/>
hudakz 6:7ff95ce72f6d 11 *
hudakz 21:7120a0dcc8ee 12 * NOTE: If you'd like to use an STM32F103C8T6 board uncomment line 23
hudakz 6:7ff95ce72f6d 13 *
hudakz 6:7ff95ce72f6d 14 * The same code is used for both NUCLEO boards, but:
hudakz 0:c5e5d0df6f2a 15 * For board #1 compile the example without any change.
hudakz 18:22977a898fe9 16 * For board #2 comment out line 23 before compiling
hudakz 4:ccf4ac2deac8 17 *
hudakz 6:7ff95ce72f6d 18 * Once the binaries have been downloaded to the boards reset board #1.
hudakz 0:c5e5d0df6f2a 19 *
hudakz 0:c5e5d0df6f2a 20 */
hudakz 0:c5e5d0df6f2a 21
hudakz 22:f4682a5ddda6 22 #define BOARD1 1 // comment out this line when compiling for board #2
hudakz 29:9ae558ec888c 23 //#define TARGET_STM32F103C8T6 1 // uncomment this line when using STM32F103C8T6 boards!
hudakz 0:c5e5d0df6f2a 24
hudakz 16:a86f339d1c25 25 #if defined(TARGET_STM32F103C8T6)
hudakz 21:7120a0dcc8ee 26 #include "stm32f103c8t6.h"
hudakz 19:872e304d7e17 27 #define LED_PIN PC_13
hudakz 10:66da8731bdb6 28 const int OFF = 1;
hudakz 10:66da8731bdb6 29 const int ON = 0;
hudakz 0:c5e5d0df6f2a 30 #else
hudakz 19:872e304d7e17 31 #define LED_PIN LED1
hudakz 10:66da8731bdb6 32 const int OFF = 0;
hudakz 10:66da8731bdb6 33 const int ON = 1;
hudakz 0:c5e5d0df6f2a 34 #endif
hudakz 0:c5e5d0df6f2a 35
hudakz 10:66da8731bdb6 36 #if defined(BOARD1)
hudakz 10:66da8731bdb6 37 const unsigned int RX_ID = 0x100;
hudakz 10:66da8731bdb6 38 const unsigned int TX_ID = 0x101;
hudakz 6:7ff95ce72f6d 39 #else
hudakz 10:66da8731bdb6 40 const unsigned int RX_ID = 0x101;
hudakz 10:66da8731bdb6 41 const unsigned int TX_ID = 0x100;
hudakz 6:7ff95ce72f6d 42 #endif
hudakz 6:7ff95ce72f6d 43
hudakz 24:e2907bcba75e 44 #include "CANnucleo.h"
hudakz 16:a86f339d1c25 45 #include "mbed.h"
hudakz 16:a86f339d1c25 46
hudakz 28:dde6c4aef759 47 Serial pc(PA_2, PA_3);
hudakz 28:dde6c4aef759 48 CAN* can;
hudakz 28:dde6c4aef759 49 CANMessage rxMsg;
hudakz 28:dde6c4aef759 50 CANMessage txMsg;
hudakz 28:dde6c4aef759 51 DigitalOut led(LED_PIN);
hudakz 28:dde6c4aef759 52 Timer timer;
hudakz 29:9ae558ec888c 53 uint8_t counter = 0; // one byte
hudakz 28:dde6c4aef759 54 AnalogIn analogIn(A0);
hudakz 29:9ae558ec888c 55 float voltage; // four bytes
hudakz 28:dde6c4aef759 56 volatile bool msgAvailable = false;
hudakz 0:c5e5d0df6f2a 57
hudakz 16:a86f339d1c25 58 /**
hudakz 29:9ae558ec888c 59 * @brief 'CAN receive-complete' interrup service routine.
hudakz 16:a86f339d1c25 60 * @note Called on arrival of new CAN message.
hudakz 16:a86f339d1c25 61 * Keep it as short as possible.
hudakz 16:a86f339d1c25 62 * @param
hudakz 16:a86f339d1c25 63 * @retval
hudakz 16:a86f339d1c25 64 */
hudakz 16:a86f339d1c25 65 void onMsgReceived() {
hudakz 16:a86f339d1c25 66 msgAvailable = true;
hudakz 16:a86f339d1c25 67 }
hudakz 16:a86f339d1c25 68
hudakz 16:a86f339d1c25 69 /**
hudakz 29:9ae558ec888c 70 * @brief Prints CAN msg to PC's serial terminal.
hudakz 25:1d0488a03905 71 * @note}
hudakz 25:1d0488a03905 72 * @param CANMessage to print
hudakz 25:1d0488a03905 73 * @retval none
hudakz 25:1d0488a03905 74 */
hudakz 28:dde6c4aef759 75 void printMsg(CANMessage& msg) {
hudakz 28:dde6c4aef759 76 pc.printf(" ID = 0x%.3x\r\n", msg.id);
hudakz 28:dde6c4aef759 77 pc.printf(" Type = %d\r\n", msg.type);
hudakz 28:dde6c4aef759 78 pc.printf(" Format = %d\r\n", msg.format);
hudakz 28:dde6c4aef759 79 pc.printf(" Length = %d\r\n", msg.len);
hudakz 28:dde6c4aef759 80 pc.printf(" Data =");
hudakz 25:1d0488a03905 81 for(int i = 0; i < msg.len; i++)
hudakz 28:dde6c4aef759 82 pc.printf(" 0x%.2X", msg.data[i]);
hudakz 28:dde6c4aef759 83 pc.printf("\r\n");
hudakz 25:1d0488a03905 84 }
hudakz 25:1d0488a03905 85
hudakz 25:1d0488a03905 86 /**
hudakz 16:a86f339d1c25 87 * @brief Main
hudakz 16:a86f339d1c25 88 * @note
hudakz 16:a86f339d1c25 89 * @param
hudakz 16:a86f339d1c25 90 * @retval
hudakz 16:a86f339d1c25 91 */
hudakz 16:a86f339d1c25 92 int main() {
hudakz 21:7120a0dcc8ee 93 #if defined(TARGET_STM32F103C8T6)
hudakz 29:9ae558ec888c 94 confSysClock(); //Configure the system clock (72MHz HSE clock, 48MHz USB clock)
hudakz 21:7120a0dcc8ee 95 #endif
hudakz 29:9ae558ec888c 96 pc.baud(9600); // set the Serial speed
hudakz 28:dde6c4aef759 97
hudakz 28:dde6c4aef759 98 can = new CAN(PA_11, PA_12); // CAN Rx pin name, CAN Tx pin name
hudakz 29:9ae558ec888c 99 can->frequency(1000000); // set the bit rate to 1Mbps
hudakz 29:9ae558ec888c 100 can->attach(&onMsgReceived); // attach the 'CAN receive-complete' interrupt service routine (ISR)
hudakz 16:a86f339d1c25 101
hudakz 0:c5e5d0df6f2a 102 #if defined(BOARD1)
hudakz 29:9ae558ec888c 103 led = ON; // turn the LED on
hudakz 29:9ae558ec888c 104 timer.start(); // start the timer
hudakz 28:dde6c4aef759 105 pc.printf("CANnucleo_Hello board #1\r\n");
hudakz 0:c5e5d0df6f2a 106 #else
hudakz 10:66da8731bdb6 107 led = OFF; // turn LED off
hudakz 28:dde6c4aef759 108 pc.printf("CANnucleo_Hello board #2\r\n");
hudakz 0:c5e5d0df6f2a 109 #endif
hudakz 0:c5e5d0df6f2a 110
hudakz 0:c5e5d0df6f2a 111 while(1) {
hudakz 23:069287e799cd 112 if(timer.read_ms() >= 1000) { // check for timeout
hudakz 29:9ae558ec888c 113 timer.stop(); // stop the timer
hudakz 29:9ae558ec888c 114 timer.reset(); // reset the timer
hudakz 29:9ae558ec888c 115 counter++; // increment the counter
hudakz 28:dde6c4aef759 116 voltage = (analogIn * 3.3f)/4096.0f;// read the small drifting voltage from analog input
hudakz 29:9ae558ec888c 117 txMsg.clear(); // clear the Tx message storage
hudakz 29:9ae558ec888c 118 txMsg.id = TX_ID; // set the message ID
hudakz 29:9ae558ec888c 119 // We are about to transmit two data items to the CAN bus.
hudakz 29:9ae558ec888c 120 // counter: uint_8 (unsigned eight bits int) value (one byte).
hudakz 29:9ae558ec888c 121 // voltage: floating point value (four bytes).
hudakz 29:9ae558ec888c 122 // So the total length of payload data is five bytes.
hudakz 29:9ae558ec888c 123 // We'll use the "<<" (append) operator to add data to the CAN message.
hudakz 29:9ae558ec888c 124 // The usage is same as of the similar C++ io-stream operators.
hudakz 29:9ae558ec888c 125 // NOTE: The data length of CAN message is automatically updated when using "<<" operators.
hudakz 25:1d0488a03905 126 txMsg << counter << voltage; // append data (total data length must be <= 8 bytes!)
hudakz 29:9ae558ec888c 127 if(can->write(txMsg)) { // transmit the CAN message
hudakz 29:9ae558ec888c 128 led = OFF; // turn the LED off
hudakz 28:dde6c4aef759 129 pc.printf("-------------------------------------\r\n");
hudakz 28:dde6c4aef759 130 pc.printf("CAN message sent\r\n");
hudakz 25:1d0488a03905 131 printMsg(txMsg);
hudakz 28:dde6c4aef759 132 pc.printf(" counter = %d\r\n", counter);
hudakz 28:dde6c4aef759 133 pc.printf(" voltage = %e V\r\n", voltage);
hudakz 25:1d0488a03905 134 }
hudakz 10:66da8731bdb6 135 else
hudakz 28:dde6c4aef759 136 pc.printf("Transmission error\r\n");
hudakz 0:c5e5d0df6f2a 137 }
hudakz 16:a86f339d1c25 138 if(msgAvailable) {
hudakz 29:9ae558ec888c 139 msgAvailable = false; // reset the flag for next use in the interrupt service routine
hudakz 29:9ae558ec888c 140 can->read(rxMsg); // read the message into the Rx message storage
hudakz 29:9ae558ec888c 141 led = ON; // turn the LED on
hudakz 28:dde6c4aef759 142 pc.printf("-------------------------------------\r\n");
hudakz 28:dde6c4aef759 143 pc.printf("CAN message received\r\n");
hudakz 25:1d0488a03905 144 printMsg(rxMsg);
hudakz 16:a86f339d1c25 145 // Filtering performed by software:
hudakz 29:9ae558ec888c 146 if(rxMsg.id == RX_ID) { // about filtering performed by hardware see the comments in CANnucleo.cpp
hudakz 29:9ae558ec888c 147 rxMsg >> counter >> voltage; // extract data from the received CAN message (in same sequence as they were added)
hudakz 28:dde6c4aef759 148 pc.printf(" counter = %d\r\n", counter);
hudakz 28:dde6c4aef759 149 pc.printf(" voltage = %e V\r\n", voltage);
hudakz 29:9ae558ec888c 150 timer.start(); // insert transmission lag
hudakz 0:c5e5d0df6f2a 151 }
hudakz 0:c5e5d0df6f2a 152 }
hudakz 0:c5e5d0df6f2a 153 }
hudakz 0:c5e5d0df6f2a 154 }
hudakz 24:e2907bcba75e 155
hudakz 24:e2907bcba75e 156
hudakz 24:e2907bcba75e 157