Diff: CAN.h

Revision:

11:1c1ebd0324fa

Child:

12:f63353af7be8

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CAN.h	Fri Aug 28 12:10:11 2009 +0000
@@ -0,0 +1,207 @@
+/* mbed Microcontroller Library - can
+ * Copyright (c) 2009 ARM Limited. All rights reserved.
+ * rmeyer
+ */ 
+
+#ifndef MBED_CAN_H
+#define MBED_CAN_H
+
+#include "Base.h"
+#include "platform.h" 
+#include "PinNames.h"
+#include "PeripheralNames.h"
+
+#include "can_helper.h" 
+
+#include <string.h>
+
+namespace mbed {
+
+/* Class: CANMessage
+ * 
+ */
+class CANMessage : public CAN_Message {
+
+public:
+
+    /* Constructor: CANMessage
+     *  Creates empty CAN message.
+     */
+    CANMessage() {
+      len    = 8;
+      type   = CANData;
+      format = CANStandard;
+      id     = 0;
+      memset(data, 0, 8);
+    }
+    
+    /* Constructor: CANMessage
+     *  Creates CAN message with specific content.
+     */
+    CANMessage(int _id, const char *_data, char _len = 8, CANType _type = CANData, CANFormat _format = CANStandard) {
+      len    = _len & 0xF;
+      type   = _type;
+      format = _format;
+      id     = _id;
+      memcpy(data, _data, _len);
+    }
+
+    /* Constructor: CANMessage
+     *  Creates CAN remote message.
+     */
+    CANMessage(int _id, CANFormat _format = CANStandard) {
+      len    = 0;
+      type   = CANRemote;
+      format = _format;
+      id     = _id;
+      memset(data, 0, 8);
+    }
+#if 0 // Inhereted from CAN_Message, for documentation only
+
+    /* Variable: id
+     *  The message id.
+     *
+     * If format is CANStandard it must be an 11 bit long id
+     * If format is CANExtended it must be an 29 bit long id
+     */
+    unsigned int   id;
+    
+    /* Variable: data
+     *  Space for 8 byte payload.
+     *
+     * If type is CANData data can store up to 8 byte data.
+     */
+    unsigned char  data[8];
+    
+    /* Variable: len
+     *  Length of data in bytes.
+     *
+     * If type is CANData data can store up to 8 byte data.
+     */
+    unsigned char  len;
+    
+    /* Variable: format
+     *  Defines if the message has standard or extended format.
+     *
+     * Defines the type of message id:
+     * Default is CANStandard which implies 11 bit id.
+     * CANExtended means 29 bit message id.
+     */
+    CANFormat      format;
+    
+    /* Variable: type
+     *  Defines the type of a message.
+     *
+     * The message type can rather be CANData for a message with data (default).
+     * Or CANRemote for a request of a specific CAN message.
+     */
+    CANType        type;               // 0 - DATA FRAME, 1 - REMOTE FRAME
+#endif
+};
+
+/* Class: CAN
+ *  A can bus client, used for communicating with can devices
+ */
+class CAN : public Base {
+
+public:
+
+    /* Constructor: CAN
+     *  Creates an CAN interface connected to specific pins.
+     *
+     * Example:
+     * > #include "mbed.h"
+     * > #include "CAN.h"
+     * > 
+     * > Ticker ticker;
+     * > DigitalOut led1(LED1);
+     * > DigitalOut led2(LED2);
+     * > CAN can1(p9, p10);
+     * > CAN can2(p30, p29);
+     * > 
+     * > char counter = 0;
+     * > 
+     * > void send() {
+     * >     if(can1.write(CANMessage(1337, &counter, 1))) {
+     * >         printf("Message sent: %d\n", counter);
+     * >         counter++;
+     * >     } 
+     * >     led1 = !led1;
+     * > }
+     * > 
+     * > int main() {
+     * >     ticker.attach(&send, 1);
+     * >    CANMessage msg;
+     * >     while(1) {
+     * >         if(can2.read(msg)) {
+     * >             printf("Message received: %d\n\n", msg.data[0]);
+     * >             led2 = !led2;
+     * >         } 
+     * >         wait(0.2);
+     * >     }
+     * > } 
+     *
+     * Variables:
+     *  rd - read from transmitter
+     *  td - transmit to transmitter
+     */
+    CAN(PinName rd, PinName td);
+    virtual ~CAN();
+    
+    /* Function: frequency
+     *  Set the frequency of the CAN interface
+     *
+     * Variables:
+     *  hz - The bus frequency in hertz
+     */
+    void frequency(int hz);
+    
+    /* Function: write
+     *  Write a CANMessage to the bus.
+     *
+     * Variables:
+     *  msg - The CANMessage to write.
+     *
+     * Returns:
+     *  0 - If write failed.
+     *  1 - If write was successful.
+     */
+    int write(CANMessage msg);
+    
+    /* Function: read
+     *  Read a CANMessage from the bus.
+     * 
+     * Variables:
+     *  msg - A CANMessage to read to.
+     *
+     * Returns:
+     *  0 - If no message arrived.
+     *  1 - If message arrived.
+     */
+    int read(CANMessage &msg);
+    
+    /* Function: reset
+     *  Reset CAN interface.
+     *
+     * To use after error overflow.
+     */
+    void reset();
+    
+    /* Function: rderror
+     *  Returns number of read errors to detect read overflow errors.
+     */
+    unsigned char rderror();
+
+    /* Function: tderror
+     *  Returns number of write errors to detect write overflow errors.
+     */
+    unsigned char tderror();
+    
+private:
+
+    CANName _id;
+};
+
+} // namespace mbed
+
+#endif    // MBED_CAN_H