Add canbus FD receive interrupt example

2026-09-14 10:33:49 +00:00 · 2020-12-10 17:10:14 +08:00
parent a1dbce2513
commit d310e299c6
1 changed files with 79 additions and 0 deletions
@@ -0,0 +1,79 @@
+// demo: CAN-BUS Shield, receive data with interrupt mode
+// when in interrupt mode, the data coming can't be too fast, must >20ms, or else you can use check mode
+// loovee, 2014-6-13
+
+#include <SPI.h>
+#include "mcp2518fd_can.h"
+
+/*SAMD core*/
+#ifdef ARDUINO_SAMD_VARIANT_COMPLIANCE
+    #define SERIAL SerialUSB
+#else
+    #define SERIAL Serial
+#endif
+
+#define CAN_2518FD
+
+// the cs pin of the version after v1.1 is default to D9
+// v0.9b and v1.0 is default D10
+const int SPI_CS_PIN = BCM8;
+const int CAN_INT_PIN = BCM25;
+
+#ifdef CAN_2518FD
+mcp2518fd CAN(SPI_CS_PIN); // Set CS pin
+#endif
+
+unsigned char flagRecv = 0;
+unsigned char len = 0;
+unsigned char buf[64];
+char str[20];
+
+void setup() {
+    SERIAL.begin(115200);
+    while (!SERIAL) {
+        ; // wait for serial port to connect. Needed for native USB port only
+    }
+    CAN.setMode(0);
+    while (0 != CAN.begin((byte)CAN_500K_1M)) {            // init can bus : baudrate = 500k    
+        SERIAL.println("CAN BUS Shield init fail");
+        SERIAL.println(" Init CAN BUS Shield again");
+        delay(100);
+    }
+    byte mode = CAN.getMode();
+    SERIAL.printf("CAN BUS get mode = %d\n\r",mode);
+    SERIAL.println("CAN BUS Shield init ok!");
+    SERIAL.println("CAN BUS Shield init ok!");
+    pinMode(CAN_INT_PIN, INPUT);
+    attachInterrupt(digitalPinToInterrupt(CAN_INT_PIN), MCP2515_ISR, FALLING); // start interrupt
+}
+
+void MCP2515_ISR() {
+    flagRecv = 1;
+}
+
+void loop() {
+    if (flagRecv) {
+        // check if get data
+
+        flagRecv = 0;                   // clear flag
+        SERIAL.println("into loop");
+        // iterate over all pending messages
+        // If either the bus is saturated or the MCU is busy,
+        // both RX buffers may be in use and reading a single
+        // message does not clear the IRQ conditon.
+        while (CAN_MSGAVAIL == CAN.checkReceive()) {
+            // read data,  len: data length, buf: data buf
+            SERIAL.println("checkReceive");
+            CAN.readMsgBuf(&len, buf);
+            // print the data
+            for (int i = 0; i < len; i++) {
+                SERIAL.print(buf[i]); SERIAL.print("\t");
+            }
+            SERIAL.println();
+        }
+    }
+}
+
+/*********************************************************************************************************
+    END FILE
+*********************************************************************************************************/