Revision 0:ff579e7e8efa, committed 2012-06-30

Comitter:

Sissors

Date:

Sat Jun 30 14:55:14 2012 +0000

Commit message:

v1.0

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MODI2C.cpp	Sat Jun 30 14:55:14 2012 +0000
@@ -0,0 +1,214 @@
+#include "MODI2C.h"
+
+MODI2C::I2CBuffer MODI2C::Buffer1 = {0,0};        //Sets the initial buffer empty and count on zero
+MODI2C::I2CBuffer MODI2C::Buffer2 = {0,0};        //Sets the initial buffer empty
+//int MODI2C::status=0;
+int MODI2C::defaultStatus=0;
+
+
+
+
+MODI2C::MODI2C(PinName sda, PinName scl) : led(LED3) {
+    //Check which connection we are using, if not correct, go to error status
+    if ((sda==p9) && (scl==p10))
+        I2CMODULE = LPC_I2C1;
+    else if ((sda==p28) && (scl==p27))
+        I2CMODULE = LPC_I2C2;
+    else
+        error("MODI2C pins not valid");
+
+    //Default settings:
+    frequency(100000);
+
+    writePinState();
+}
+
+int MODI2C::write(int address, char *data, int length, bool repeated, int *status) {
+
+    I2CData Data;
+    //Store relevant information
+    address &= 0xFE;
+    Data.caller = this;
+    Data.address = address;
+    Data.repeated = repeated;
+    Data.data = data;
+    Data.length = length;
+    Data.status = status;
+
+    while(!addBuffer(Data, I2CMODULE));
+
+    return 0;
+}
+
+int MODI2C::write(int address, char *data, int length, int *status) {
+    return write(address, data, length, false, status);
+    }
+
+int MODI2C::read_nb(int address, char *data, int length, bool repeated, int *status) {
+    //Store relevant information
+    address |= 0x01;
+
+    //isIdle check here
+    I2CData Data;
+
+
+    Data.caller = this;
+    Data.address = address;
+    Data.repeated = repeated;
+    Data.data = data;
+    Data.length = length;
+    Data.status = status;
+
+    while(!addBuffer(Data, I2CMODULE));
+
+    return 0;
+}
+
+int MODI2C::read_nb(int address, char *data, int length, int *status) {
+    return read_nb(address, data, length, false, status);
+    }
+
+int MODI2C::read(int address, char *data, int length, bool repeated) {
+    int stat;
+    //Store relevant information
+    address |= 0x01;
+
+    //isIdle check here
+    I2CData Data;
+
+
+    Data.caller = this;
+    Data.address = address;
+    Data.repeated = repeated;
+    Data.data = data;
+    Data.length = length;
+    Data.status = &stat;
+
+    while(!addBuffer(Data, I2CMODULE));
+    
+    I2CBuffer *Buffer;
+    if (I2CMODULE == LPC_I2C1) {
+        Buffer = &Buffer1;
+    } else {
+        Buffer = &Buffer2;
+    }
+    
+    while(Buffer->queue!=0)
+        wait_us(1);
+    
+    if (stat==0x58)         //Return zero if ended correctly, otherwise return return code.
+        return 0;
+    else
+        return stat;
+}
+
+
+void MODI2C::start( void ) {
+    _start(I2CMODULE);
+}
+
+void MODI2C::stop( void ) {
+    _stop(I2CMODULE);
+}
+
+void MODI2C::frequency(int hz) {
+    //The I2C clock by default runs on quarter of system clock, which is 96MHz
+    //So to calculate high/low count times, we do 96MHz/4/2/frequency
+    duty = 96000000/8/hz;
+    if (duty>65535)
+        duty=65535;
+    if (duty<4)
+        duty=4;
+}
+
+int MODI2C::getQueue( void ) {
+    I2CBuffer *Buffer;
+    if (I2CMODULE == LPC_I2C1) {
+        Buffer = &Buffer1;
+    } else {
+        Buffer = &Buffer2;
+    }
+    return Buffer->queue;
+    }
+
+
+
+//*******************************************
+//***********Internal functions**************
+//*******************************************
+
+
+void MODI2C::writeSettings( void ) {
+    I2CMODULE->I2CONSET = 1<<I2C_ENABLE;     //Enable I2C
+    I2CMODULE->I2CONCLR = I2C_STOP;
+    I2CMODULE->MMCTRL = 0;                   //Disable monitor mode
+    I2CMODULE->I2SCLH = duty;
+    I2CMODULE->I2SCLL = duty;
+
+}
+
+void MODI2C::writePinState( void ) {
+    if (I2CMODULE == LPC_I2C1) {
+        LPC_PINCON->PINSEL0 |= 0x0000000F;       //Sets pins as I2C
+        LPC_PINCON->PINMODE0 |= 0x0000000A;      //Neither pull up nor pull down
+        LPC_PINCON->PINMODE_OD0 |= 0x00000003;   //Open drain mode enabled
+    } else if (I2CMODULE == LPC_I2C2) {
+        LPC_PINCON->PINSEL0 |= (1<<21)|(1<<23); //Same story, different register settings
+        LPC_PINCON->PINMODE0 |= (1<<21)|(1<<23);
+        LPC_PINCON->PINMODE_OD0 |= (1<<10)|(1<<11);
+    }
+}
+
+
+
+void MODI2C::attach( void (*function)(void), int operation) {
+    IRQOp = operation;
+    callback.attach(function);
+}
+
+template<typename T>
+void MODI2C::attach(T *object, void (T::*member)(void), int operation) {
+    IRQOp = operation;
+    callback.attach(object, member);
+}
+
+void MODI2C::detach( void ) {
+    callback.attach(NULL);
+}
+
+void MODI2C::_start(LPC_I2C_TypeDef *I2CMODULE) {
+    if (!(I2CMODULE->I2CONSET & 1<<I2C_START))  //If already sent, skip
+        I2CMODULE->I2CONSET = 1<<I2C_START;     //Send start condition
+}
+
+void MODI2C::_stop(LPC_I2C_TypeDef *I2CMODULE) {
+    I2CMODULE->I2CONSET = 1<<I2C_STOP;      //Send stop condition
+    I2CMODULE->I2CONCLR = 1<<I2C_FLAG;
+}
+
+//Set interrupt vector
+void MODI2C::setISR(void) {
+    _setISR(I2CMODULE);
+}
+
+void MODI2C::_setISR(LPC_I2C_TypeDef *I2CMODULE) {
+    if (I2CMODULE == LPC_I2C1) {
+        NVIC_SetVector(I2C1_IRQn, (uint32_t)&IRQ1Handler);
+        NVIC_EnableIRQ(I2C1_IRQn);
+    } else if (I2CMODULE == LPC_I2C2) {
+        NVIC_SetVector(I2C2_IRQn, (uint32_t)&IRQ2Handler);
+        NVIC_EnableIRQ(I2C2_IRQn);
+    }
+}
+
+void MODI2C::clearISR( void ) {
+    _clearISR(I2CMODULE);
+}
+
+void MODI2C::_clearISR( LPC_I2C_TypeDef *I2CMODULE ) {
+    if (I2CMODULE == LPC_I2C1) {
+        NVIC_DisableIRQ(I2C1_IRQn);
+    } else if (I2CMODULE == LPC_I2C2) {
+        NVIC_DisableIRQ(I2C2_IRQn);
+    }
+}

--- /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

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MODI2C_IRQ.cpp	Sat Jun 30 14:55:14 2012 +0000
@@ -0,0 +1,228 @@
+#include "MODI2C.h"
+
+//**********************************************************
+//*********************IRQ FUNCTIONS************************
+//**********************************************************
+
+
+void MODI2C::runUserIRQ(I2CData Data) {
+     
+    if (IRQOp==IRQ_I2C_BOTH)        //Always call if both
+        callback.call();
+    if ((IRQOp==IRQ_I2C_READ)&&(Data.address&0x01)) //Call if read and byte was read
+        callback.call();
+    if ((IRQOp==IRQ_I2C_WRITE)&&(!(Data.address&0x01))) //Call if write and byte was written
+        callback.call();
+}
+
+void MODI2C::IRQ1Handler( void ) {
+    IRQHandler(&Buffer1, LPC_I2C1);
+}
+
+void MODI2C::IRQ2Handler( void ) {
+    IRQHandler(&Buffer2, LPC_I2C2);
+}
+
+void MODI2C::IRQHandler( I2CBuffer *Buffer, LPC_I2C_TypeDef *I2CMODULE) {
+    I2CData *Data = &Buffer->Data[0];
+
+    //Depending on the status register it determines next action, see datasheet
+    //This is also pretty much copy pasting the datasheet
+    //General options
+    switch (I2CMODULE->I2STAT) {
+        case(0x08):
+        case(0x10):
+            //Send Address
+            I2CMODULE->I2DAT = Data->address;
+            I2CMODULE->I2CONCLR = 1<<I2C_FLAG | 1<<I2C_START;
+            break;
+
+            //All master TX options
+
+            //Address + W has been sent, ACK received
+            //Data has been sent, ACK received
+        case(0x18):
+        case(0x28):
+            if (Buffer->count==Data->length) {
+                *Data->status=I2CMODULE->I2STAT;
+                if (!Data->repeated)
+                    _stop(I2CMODULE);
+                else {
+                    I2CMODULE->I2CONSET = 1<<I2C_START;
+                    I2CMODULE->I2CONCLR = 1<<I2C_FLAG;
+                }
+                bufferHandler(I2CMODULE);
+            } else {
+                I2CMODULE->I2DAT = Data->data[Buffer->count];
+                I2CMODULE->I2CONSET = 1<<I2C_ASSERT_ACK;        //I dont see why I have to enable that bit, but datasheet says so
+                I2CMODULE->I2CONCLR = 1<<I2C_FLAG;
+                Buffer->count++;
+            }
+            break;
+
+            //Address + W has been sent, NACK received
+            //Data has been sent, NACK received
+        case(0x20):
+        case(0x30):
+            *Data->status=I2CMODULE->I2STAT;
+            _stop(I2CMODULE);
+            bufferHandler(I2CMODULE);
+            break;
+
+            //Arbitration lost (situation looks pretty hopeless to me if you arrive here)
+        case(0x38):
+            _start(I2CMODULE);
+            break;
+
+
+            //All master RX options
+
+            //Address + R has been sent, ACK received
+        case(0x40):
+            //If next byte is last one, NACK, otherwise ACK
+            if (Data->length <= Buffer->count + 1)
+                I2CMODULE->I2CONCLR = 1<<I2C_ASSERT_ACK;
+            else
+                I2CMODULE->I2CONSET = 1<<I2C_ASSERT_ACK;
+            I2CMODULE->I2CONCLR = 1<<I2C_FLAG;
+            break;
+
+            //Address + R has been sent, NACK received
+        case(0x48):
+            *Data->status=I2CMODULE->I2STAT;
+            _stop(I2CMODULE);
+            bufferHandler(I2CMODULE);
+            break;
+
+            //Data was received, ACK returned
+        case(0x50):
+            //Read data
+            Data->data[Buffer->count]=I2CMODULE->I2DAT;
+            Buffer->count++;
+
+            //If next byte is last one, NACK, otherwise ACK
+            if (Data->length == Buffer->count + 1)
+                I2CMODULE->I2CONCLR = 1<<I2C_ASSERT_ACK;
+            else
+                I2CMODULE->I2CONSET = 1<<I2C_ASSERT_ACK;
+
+            I2CMODULE->I2CONCLR = 1<<I2C_FLAG;
+            break;
+
+            //Data was received, NACK returned (last byte)
+        case(0x58):
+            //Read data
+            *Data->status=I2CMODULE->I2STAT;
+            Data->data[Buffer->count]=I2CMODULE->I2DAT;
+            if (!Data->repeated)
+                _stop(I2CMODULE);
+            else {
+                I2CMODULE->I2CONSET = 1<<I2C_START;
+                I2CMODULE->I2CONCLR = 1<<I2C_FLAG;
+            }
+            bufferHandler(I2CMODULE);
+            break;
+
+        default:
+            *Data->status=I2CMODULE->I2STAT;
+            bufferHandler(I2CMODULE);
+            break;
+    }
+}
+
+
+//**********************************************************
+//*********************COMMAND BUFFER***********************
+//**********************************************************
+
+void MODI2C::bufferHandler(LPC_I2C_TypeDef *I2CMODULE) {
+    I2CBuffer *Buffer;
+    if (I2CMODULE == LPC_I2C1) {
+        Buffer = &Buffer1;
+    } else {
+        Buffer = &Buffer2;
+    }
+
+    //Start user interrupt
+    Buffer->Data[0].caller->runUserIRQ(Buffer->Data[0]);
+
+    removeBuffer(I2CMODULE);
+
+
+
+    if (Buffer->queue!=0)
+        startBuffer(I2CMODULE);
+    else
+        _clearISR(I2CMODULE);
+}
+
+//Returns true if succeeded, false if buffer is full
+bool MODI2C::addBuffer(I2CData Data, LPC_I2C_TypeDef *I2CMODULE) {
+    I2CBuffer *Buffer;
+    if (I2CMODULE == LPC_I2C1) {
+        Buffer = &Buffer1;
+    } else {
+        Buffer = &Buffer2;
+    }
+    if (Buffer->queue<I2C_BUFFER) {
+        
+        if(Data.status == NULL) {
+            Data.status = &defaultStatus;
+            wait_us(1);     //I blame the compiler that this is needed
+            }
+        *Data.status = 0;
+            
+        Buffer->Data[Buffer->queue]=Data;
+        Buffer->queue++;
+
+        //If queue was empty, set I2C settings, start conversion
+        if (Buffer->queue==1) {
+            startBuffer(I2CMODULE);
+        }
+
+        return true;
+    } else
+        return false;
+
+}
+
+//Returns true if buffer still has data, false if empty
+bool MODI2C::removeBuffer(LPC_I2C_TypeDef *I2CMODULE) {
+    I2CBuffer *Buffer;
+    if (I2CMODULE == LPC_I2C1) {
+        Buffer = &Buffer1;
+    } else {
+        Buffer= &Buffer2;
+    }
+
+    if (Buffer->queue>0) {
+        for (int i =0; i<Buffer->queue-1; i++)
+            Buffer->Data[i]=Buffer->Data[i+1];
+        Buffer->queue--;
+    }
+    if (Buffer->queue>0)
+        return true;
+    else
+        return false;
+}
+
+//Starts new conversion
+void MODI2C::startBuffer(LPC_I2C_TypeDef *I2CMODULE) {
+    I2CBuffer *Buffer;
+    if (I2CMODULE == LPC_I2C1) {
+        Buffer = &Buffer1;
+    } else {
+        Buffer = &Buffer2;
+    }
+
+    //Write settings
+    Buffer->Data[0].caller->writeSettings();
+    Buffer->count=0;
+
+    //Send Start
+    _start(I2CMODULE);
+
+    //Start ISR (when buffer wasnt empty this wont do anything)
+    _setISR(I2CMODULE);
+
+}
\ No newline at end of file