pub
Dependencies: CANnucleo mbed-dev
Fork of CANnucleo_Hello by
main.cpp
- Committer:
- hudakz
- Date:
- 2017-03-14
- Revision:
- 30:9ae558ec888c
- Parent:
- 29:dde6c4aef759
File content as of revision 30:9ae558ec888c:
/* * An example showing how to use the CANnucleo library: * * Two affordable (less than $3 on ebay) STM32F103C8T6 boards (20kB SRAM, 64kB Flash), * (see [https://developer.mbed.org/users/hudakz/code/STM32F103C8T6_Hello/] for more details) * are connected to the same CAN bus via transceivers (MCP2551 or TJA1040, or etc.). * CAN transceivers are not part of NUCLEO boards, therefore must be added by you. * Remember also that CAN bus (even a short one) must be terminated with 120 Ohm resitors at both ends. * * For more details see the wiki page <https://developer.mbed.org/users/hudakz/code/CANnucleo_Hello/> * * NOTE: If you'd like to use an STM32F103C8T6 board uncomment line 23 * * The same code is used for both NUCLEO boards, but: * For board #1 compile the example without any change. * For board #2 comment out line 23 before compiling * * Once the binaries have been downloaded to the boards reset board #1. * */ #define BOARD1 1 // comment out this line when compiling for board #2 //#define TARGET_STM32F103C8T6 1 // uncomment this line when using STM32F103C8T6 boards! #if defined(TARGET_STM32F103C8T6) #include "stm32f103c8t6.h" #define LED_PIN PC_13 const int OFF = 1; const int ON = 0; #else #define LED_PIN LED1 const int OFF = 0; const int ON = 1; #endif #if defined(BOARD1) const unsigned int RX_ID = 0x100; const unsigned int TX_ID = 0x101; #else const unsigned int RX_ID = 0x101; const unsigned int TX_ID = 0x100; #endif #include "CANnucleo.h" #include "mbed.h" Serial pc(PA_2, PA_3); CAN* can; CANMessage rxMsg; CANMessage txMsg; DigitalOut led(LED_PIN); Timer timer; uint8_t counter = 0; // one byte AnalogIn analogIn(A0); float voltage; // four bytes volatile bool msgAvailable = false; /** * @brief 'CAN receive-complete' interrup service routine. * @note Called on arrival of new CAN message. * Keep it as short as possible. * @param * @retval */ void onMsgReceived() { msgAvailable = true; } /** * @brief Prints CAN msg to PC's serial terminal. * @note} * @param CANMessage to print * @retval none */ void printMsg(CANMessage& msg) { pc.printf(" ID = 0x%.3x\r\n", msg.id); pc.printf(" Type = %d\r\n", msg.type); pc.printf(" Format = %d\r\n", msg.format); pc.printf(" Length = %d\r\n", msg.len); pc.printf(" Data ="); for(int i = 0; i < msg.len; i++) pc.printf(" 0x%.2X", msg.data[i]); pc.printf("\r\n"); } /** * @brief Main * @note * @param * @retval */ int main() { #if defined(TARGET_STM32F103C8T6) confSysClock(); //Configure the system clock (72MHz HSE clock, 48MHz USB clock) #endif pc.baud(9600); // set the Serial speed can = new CAN(PA_11, PA_12); // CAN Rx pin name, CAN Tx pin name can->frequency(1000000); // set the bit rate to 1Mbps can->attach(&onMsgReceived); // attach the 'CAN receive-complete' interrupt service routine (ISR) #if defined(BOARD1) led = ON; // turn the LED on timer.start(); // start the timer pc.printf("CANnucleo_Hello board #1\r\n"); #else led = OFF; // turn LED off pc.printf("CANnucleo_Hello board #2\r\n"); #endif while(1) { if(timer.read_ms() >= 1000) { // check for timeout timer.stop(); // stop the timer timer.reset(); // reset the timer counter++; // increment the counter voltage = (analogIn * 3.3f)/4096.0f;// read the small drifting voltage from analog input txMsg.clear(); // clear the Tx message storage txMsg.id = TX_ID; // set the message ID // We are about to transmit two data items to the CAN bus. // counter: uint_8 (unsigned eight bits int) value (one byte). // voltage: floating point value (four bytes). // So the total length of payload data is five bytes. // We'll use the "<<" (append) operator to add data to the CAN message. // The usage is same as of the similar C++ io-stream operators. // NOTE: The data length of CAN message is automatically updated when using "<<" operators. txMsg << counter << voltage; // append data (total data length must be <= 8 bytes!) if(can->write(txMsg)) { // transmit the CAN message led = OFF; // turn the LED off pc.printf("-------------------------------------\r\n"); pc.printf("CAN message sent\r\n"); printMsg(txMsg); pc.printf(" counter = %d\r\n", counter); pc.printf(" voltage = %e V\r\n", voltage); } else pc.printf("Transmission error\r\n"); } if(msgAvailable) { msgAvailable = false; // reset the flag for next use in the interrupt service routine can->read(rxMsg); // read the message into the Rx message storage led = ON; // turn the LED on pc.printf("-------------------------------------\r\n"); pc.printf("CAN message received\r\n"); printMsg(rxMsg); // Filtering performed by software: if(rxMsg.id == RX_ID) { // about filtering performed by hardware see the comments in CANnucleo.cpp rxMsg >> counter >> voltage; // extract data from the received CAN message (in same sequence as they were added) pc.printf(" counter = %d\r\n", counter); pc.printf(" voltage = %e V\r\n", voltage); timer.start(); // insert transmission lag } } } }