Diff: MODI2C.h

Revision:

0:ff579e7e8efa

Child:

1:eed116eb680a

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MODI2C.h	Sat Jun 30 14:55:14 2012 +0000
@@ -0,0 +1,248 @@
+/* 
+
+                            .       .
+                           / `.   .' \
+                   .---.  <    > <    >  .---.
+                   |    \  \ - ~ ~ - /  /    |
+                    ~-..-~             ~-..-~
+                \~~~\.'                    `./~~~/
+                 \__/                        \__/
+                  /                  .-    .  \
+           _._ _.-    .-~ ~-.       /       }   \/~~~/
+       _.-'q  }~     /       }     {        ;    \__/
+      {'__,  /      (       /      {       /      `. ,~~|   .     .
+       `''''='~~-.__(      /_      |      /- _      `..-'   \\   //
+                   / \   =/  ~~--~~{    ./|    ~-.     `-..__\\_//_.-'
+                  {   \  +\         \  =\ (        ~ - . _ _ _..---~
+                  |  | {   }         \   \_\
+                 '---.o___,'       .o___,'     "Stegosaurus"
+
+
+Face it, dinos much cooler than copyright notices.*/
+
+#include "mbed.h"
+
+
+#ifndef MODI2C_H
+#define MODI2C_H
+
+
+#define I2C_ENABLE          6
+#define I2C_START           5
+#define I2C_STOP            4
+#define I2C_FLAG            3
+#define I2C_ASSERT_ACK      2
+
+#define IRQ_I2C_BOTH        0
+#define IRQ_I2C_READ        1
+#define IRQ_I2C_WRITE       2
+
+
+
+#ifndef I2C_BUFFER
+#define I2C_BUFFER          10
+#endif
+
+
+/** Library that allows interrupt driven communication with I2C devices
+  *
+  * For now this is all in beta, so if you got weird results while the mbed I2C library works, it is probably my fault.
+  * Similar to googles definition of beta, it is unlikely it will ever come out of beta.
+  *
+  * Example:
+  * @code
+  * #include "mbed.h"
+  * #include "MODI2C.h"
+  * #include "MPU6050.h"
+  * 
+  * Serial pc(USBTX, USBRX); // tx, rx
+  * MODI2C mod(p9, p10);
+  * 
+  * int main() {
+  *     char registerAdd = MPU6050_WHO_AM_I_REG;
+  *     char registerResult;
+  *     int status;
+  * 
+  *     while (1) {
+  *         mod.write(MPU6050_ADDRESS*2, &registerAdd, 1, true);
+  *         mod.read_nb(MPU6050_ADDRESS*2, &registerResult, 1, &status);
+  * 
+  *         while (!status) wait_us(1);
+  *         pc.printf("Register holds 0x%02X\n\r", registerResult);
+  *         wait(2);
+  *     }
+  * }
+  * @endcode
+  */
+class MODI2C {
+public:
+    /**
+    * Constructor.
+    *
+    * @param sda - mbed pin to use for the SDA I2C line.
+    * @param scl - mbed pin to use for the SCL I2C line.
+    */
+    MODI2C(PinName sda, PinName scl);
+
+    /**
+    * Write data on the I2C bus.
+    *
+    * This function should generally be a drop-in replacement for the standard mbed write function.
+    * However this function is completely non-blocking, so it barely takes time. This can cause different behavior.
+    * Everything else is similar to read_nb.
+    *
+    * @param address - I2C address of the slave (7 bit address << 1).
+    * @param data - pointer to byte array that holds the data
+    * @param length - amount of bytes that need to be sent
+    * @param repeated - determines if it should end with a stop condition (default false)
+    * @param status - (optional) pointer to integer where the final status code of the I2C transmission is placed. (0x28 is success)
+    * @param return - returns zero
+    */
+    int write(int address, char *data, int length, bool repeated = false, int *status = NULL);
+    int write(int address, char *data, int length, int *status);
+
+    /**
+    * Read data non-blocking from the I2C bus.
+    *
+    * Reads data from the I2C bus, completely non-blocking. Aditionally it will always return zero, since it does
+    * not wait to see how the transfer goes. A pointer to an integer can be added as argument which returns the status.
+    *
+    * @param address - I2C address of the slave (7 bit address << 1).
+    * @param data - pointer to byte array where the data will be stored
+    * @param length - amount of bytes that need to be received
+    * @param repeated - determines if it should end with a stop condition
+    * @param status - (optional) pointer to integer where the final status code of the I2C transmission is placed. (0x58 is success)
+    * @param return - returns zero
+    */
+    int read_nb(int address, char *data, int length, bool repeated = false, int *status=NULL);
+    int read_nb(int address, char *data, int length, int *status);
+    
+    /**
+    * Read data from the I2C bus.
+    *
+    * This function should should be a drop-in replacement for the standard mbed function.
+    *
+    * @param address - I2C address of the slave (7 bit address << 1).
+    * @param data - pointer to byte array where the data will be stored
+    * @param length - amount of bytes that need to be received
+    * @param repeated - determines if it should end with a stop condition
+    * @param return - returns zero on success, LPC status code on failure
+    */
+    int read(int address, char *data, int length, bool repeated = false);
+
+    /**
+    * Sets the I2C bus frequency
+    *
+    * @param hz - the bus frequency in herz
+    */
+    void frequency(int hz);
+
+    /**
+    * Creates a start condition on the I2C bus
+    *
+    * If you use this function you probably break something (but mbed also had it public)
+    */
+    void start ( void );
+
+    /**
+    * Creates a stop condition on the I2C bus
+    *
+    * If you use this function you probably break something (but mbed also had it public)
+    */
+    void stop ( void );
+    
+    /**
+    * Removes attached function
+    */
+    void detach( void );
+    
+    /**
+    * Calls user function when I2C command is finished
+    *
+    * @param function - the function to call.
+    * @param operation - when to call IRQ: IRQ_I2C_BOTH (default) - IRQ_I2C_READ - IRQ_I2C_WRITE
+    */
+    void attach(void (*function)(void), int operation = IRQ_I2C_BOTH);
+    
+    /**
+    * Calls user function when I2C command is finished
+    *
+    * @param object - the object to call the function on.
+    * @param member - the function to call
+    * @param operation - when to call IRQ: IRQ_I2C_BOTH (default) - IRQ_I2C_READ - IRQ_I2C_WRITE
+    */
+    template<typename T>
+        void attach(T *object, void (T::*member)(void), int operation = IRQ_I2C_BOTH);
+        
+    /**
+    * Returns the current number of commands in the queue (including one currently being processed)
+    *
+    * Note that this is the number of commands, not the number of bytes
+    *
+    * @param return - number of commands in queue
+    */
+    int getQueue( void );
+
+
+private:
+
+    struct I2CData {
+        MODI2C *caller;
+        char address;
+        char *data;
+        int  length;
+        bool repeated;
+        int *status;
+    };
+    
+    struct I2CBuffer {
+        int queue;
+        int count;
+        I2CData Data[I2C_BUFFER];
+        };
+        
+    //Settings:
+    int duty;
+    
+    FunctionPointer callback;
+    int IRQOp;   
+    void runUserIRQ( I2CData Data );
+
+    //Remove later:
+    LPC_I2C_TypeDef *I2CMODULE;
+
+    
+
+    //Whole bunch of static stuff, pretty much everything that is ever called from ISR
+    static I2CBuffer Buffer1;
+    static I2CBuffer Buffer2;
+    
+    static void IRQHandler(I2CBuffer *Buffer, LPC_I2C_TypeDef *I2CMODULE);
+    static void IRQ1Handler(void);
+    static void IRQ2Handler(void);
+    
+    static void bufferHandler(LPC_I2C_TypeDef *I2CMODULE);
+    static bool addBuffer(I2CData Data, LPC_I2C_TypeDef *I2CMODULE);
+    static bool removeBuffer(LPC_I2C_TypeDef *I2CMODULE);
+    static void startBuffer(LPC_I2C_TypeDef *I2CMODULE);
+
+    static int defaultStatus;
+    
+    static void _start(LPC_I2C_TypeDef *I2CMODULE);
+    static void _stop(LPC_I2C_TypeDef *I2CMODULE);
+    static void _clearISR( LPC_I2C_TypeDef *I2CMODULE );
+    static void _setISR( LPC_I2C_TypeDef *I2CMODULE );
+
+
+    void writeSettings( void );
+    void writePinState( void );
+    void setISR( void );
+    void clearISR( void );
+
+
+    DigitalOut led;
+
+};
+
+
+#endif
\ No newline at end of file