I2cRtosDriver

Revision 13:530968937ccb, committed 2013-05-10

Comitter:

humlet

Date:

Fri May 10 20:38:35 2013 +0000

Parent:

12:6ddadcbbdca2

Child:

14:352609d395c1

Commit message:

happyhappyjoyjoy

Changed in this revision

--- a/I2CDriver.cpp	Fri May 10 07:34:24 2013 +0000
+++ b/I2CDriver.cpp	Fri May 10 20:38:35 2013 +0000
@@ -5,7 +5,10 @@
 using namespace mbed;
 using namespace rtos;
 
-#define DRV_USR_SIG (1<<6)
+#define PREFIX i2c
+#define PASTER(x,y) x ## _ ## y
+#define EVALUATOR(x,y)  PASTER(x,y)
+#define FUNCTION(fun) EVALUATOR(PREFIX, fun)
 
 const PinName I2CDriver::c_sdas[] = {p9,p28};
 const PinName I2CDriver::c_scls[] = {p10,p27};
@@ -14,6 +17,8 @@
 
 I2CDriver::I2CDriver(PinName sda, PinName scl, int hz, int slaveAdr):m_freq(hz),m_slaveAdr(slaveAdr)
 {
+    static Mutex mutex;
+    mutex.lock();
     // check pins and determine i2c channel
     int channel=0;
 #if defined(TARGET_LPC1768) || defined(TARGET_LPC2368)
@@ -24,89 +29,15 @@
         else error("I2CDriver: Invalid I2C pins selected\n");
 
     if(s_channels[channel]==0) {
-        new Thread(threadFun,(void *)channel,osPriorityRealtime,1024);  // evillive
+        s_channels[channel] = new I2CDriver::Channel;
+        m_channel = s_channels[channel];
+        m_channel->freq = 0;
+        m_channel->slaveAdr = 0;
+        m_channel->modeSlave = 0;
+        FUNCTION(init)(&m_channel->i2c, c_sdas[channel], c_scls[channel]);
     }
     m_channel = s_channels[channel];
-}
-
-
-void I2CDriver::threadFun(void const *args)
-{
-    int channelIdx = (int)args;
-    Channel channel;
-    s_channels[channelIdx] = &channel;
-    channel.driver = Thread::gettid();
-
-    int freq = 0;
-    int adrSlave = 0;
-    int modeSlave = 0;
-    i2c_t i2c;
-    i2cRtos_init(&i2c, c_sdas[channelIdx], c_scls[channelIdx]);
-
-    volatile Transfer& tr = channel.transfer;
-    while(1) {
-        // wait for requests
-        osSignalWait(DRV_USR_SIG,osWaitForever);
-
-        // check and adapt frequency
-        if(freq != tr.freq) {
-            freq = tr.freq;
-            i2c_frequency(&i2c, tr.freq);
-        }
-
-        // check and adapt slave/master mode
-        if(modeSlave != tr.slv) {
-            modeSlave = tr.slv;
-            i2c_slave_mode(&i2c, tr.slv);
-        }
-
-        // check and adapt slave address
-        int adr = (tr.adr & 0xFF) | 1;
-        if(tr.slv && adrSlave != adr) {
-            adrSlave = adr;
-            i2c_slave_address(&i2c, 0, adr, 0);
-        }
-
-        // just doit
-        switch(tr.cmd) {
-            case START:
-                i2c_start(&i2c);
-                break;
-            case STOP:
-                i2c_stop(&i2c);
-                break;
-            case READ_MST:
-                tr.ret = i2cRtos_read(&i2c, tr.adr, tr.dta, tr.len, (tr.rep?0:1));
-                break;
-            case READ_MST_REG:
-                tr.ret = i2cRtos_write(&i2c, tr.adr,(const char*)&(tr.reg), 1, 0);
-                if(tr.ret)break; // error => bail out
-                tr.ret = i2cRtos_read(&i2c, tr.adr, tr.dta, tr.len, (tr.rep?0:1));
-                break;
-            case READ_SLV:
-                tr.ret = i2cRtos_slave_read(&i2c, tr.dta, tr.len);
-                break;
-            case READ_BYTE:
-                tr.ret = i2cRtos_byte_read(&i2c, (tr.ack?0:1));
-                break;
-            case WRITE_MST:
-                tr.ret = i2cRtos_write(&i2c, tr.adr, tr.wdta, tr.len, (tr.rep?0:1));
-                break;
-            case WRITE_SLV:
-                tr.ret = i2cRtos_slave_write(&i2c, tr.wdta, tr.len);
-                break;
-            case WRITE_BYTE:
-                tr.ret = i2cRtos_byte_write(&i2c, tr.ack);
-                break;
-            case RECEIVE:
-                tr.ret = i2cRtos_slave_receive(&i2c, tr.tmout);
-                break;
-            default:
-                error("call 911\n");
-        }
-        // inform the caller
-        osSignalSet( channel.transfer.caller, DRV_USR_SIG);
-    }
+    mutex.unlock();
 }
 
 void I2CDriver::lock()
@@ -116,157 +47,140 @@
     m_callerID = osThreadGetId();
     m_callerPrio = osThreadGetPriority(m_callerID);
     m_channel->mutex.lock(osWaitForever);
-    osThreadSetPriority(m_callerID, c_drvPrio); // evillive hopefully not interrupted since the lock
+    // maximize thread prio
+    osThreadSetPriority(m_callerID, c_drvPrio); // hopefully not interrupted since the lock in the line above
+    // mutex code looks like that waiting threads are priority ordered
+    // also priority inheritance seems to be provided
 }
 
 void I2CDriver::unlock()
 {
-    // free the mtex and restore original prio
+    // free the mutex and restore original prio
     m_channel->mutex.unlock();
     osThreadSetPriority(m_callerID, m_callerPrio);
 }
 
-int I2CDriver::sendNwait()
+void I2CDriver::config()
 {
-    m_channel->transfer.freq = m_freq;
-    m_channel->transfer.caller = Thread::gettid();
-    osSignalSet( m_channel->driver, DRV_USR_SIG);
-    osSignalWait(DRV_USR_SIG,osWaitForever);
-    int ret = m_channel->transfer.ret;
-    unlock();
-    return ret;
+    // check and update frequency
+    if(m_freq != m_channel->freq) {
+        m_channel->freq = m_freq;
+        i2c_frequency(&m_channel->i2c, m_freq);
+    }
+    // check and update slave/master mode
+    if(m_modeSlave != m_channel->modeSlave) {
+        m_channel->modeSlave = m_modeSlave;
+        i2c_slave_mode(&m_channel->i2c, m_modeSlave);
+    }
+    // check and update slave address
+    if(m_modeSlave && m_slaveAdr != m_channel->slaveAdr) {
+        m_channel->slaveAdr = m_slaveAdr;
+        i2c_slave_address(&m_channel->i2c, 0, m_slaveAdr, 0);
+    }
 }
 
 int I2CDriver::readMaster(int address, char *data, int length, bool repeated)
 {
-    lock();
-    m_channel->transfer.cmd = READ_MST;
-    m_channel->transfer.slv = false;
-    m_channel->transfer.adr = address;
-    m_channel->transfer.dta = data;
-    m_channel->transfer.len = length;
-    m_channel->transfer.rep = repeated;
-    return sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    int ret = FUNCTION(read)(&m_channel->i2c, address, data, length, (repeated?0:1));
+    unlock();
+    return ret;
 }
-
 int I2CDriver::readMaster(int address, uint8_t _register, char *data, int length, bool repeated)
 {
-    lock();
-    m_channel->transfer.cmd = READ_MST_REG;
-    m_channel->transfer.slv = false;
-    m_channel->transfer.adr = address;
-    m_channel->transfer.reg = _register;
-    m_channel->transfer.dta = data;
-    m_channel->transfer.len = length;
-    m_channel->transfer.rep = repeated;
-    return sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    int ret = FUNCTION(write)(&m_channel->i2c, address,(const char*)&_register, 1, 0);
+    if(!ret) ret = FUNCTION(read)(&m_channel->i2c, address, data, length, (repeated?0:1));
+    unlock();
+    return ret;
 }
-
 int I2CDriver::readMaster(int ack)
 {
-    lock();
-    m_channel->transfer.cmd = READ_BYTE;
-    m_channel->transfer.slv = false;
-    m_channel->transfer.ack = ack;
-    return sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    int ret = i2cRtos_byte_read(&m_channel->i2c, (ack?0:1));
+    unlock();
+    return ret;
 }
-
 int I2CDriver::writeMaster(int address, const char *data, int length, bool repeated)
 {
-    lock();
-    m_channel->transfer.cmd = WRITE_MST;
-    m_channel->transfer.slv = false;
-    m_channel->transfer.adr = address;
-    m_channel->transfer.wdta = data;
-    m_channel->transfer.len = length;
-    m_channel->transfer.rep = repeated;
-    return sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    int ret = FUNCTION(write)(&m_channel->i2c, address, data, length, (repeated?0:1));
+    unlock();
+    return ret;
 }
-
 int I2CDriver::writeMaster(int data)
 {
-    lock();
-    m_channel->transfer.cmd = WRITE_BYTE;
-    m_channel->transfer.slv = false;
-    m_channel->transfer.ack = data;
-    return sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    int ret = i2cRtos_byte_write(&m_channel->i2c, data);
+    unlock();
+    return ret;
 }
-
 void I2CDriver::startMaster(void)
 {
-    lock();
-    m_channel->transfer.cmd = START;
-    m_channel->transfer.slv = false;
-    sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    i2c_start(&m_channel->i2c);
+    unlock();
 }
-
-void I2CDriver::stopMaster(void)
+bool I2CDriver::stopMaster(void)
 {
-    lock();
-    m_channel->transfer.cmd = STOP;
-    m_channel->transfer.slv = false;
-    sendNwait();
+    m_modeSlave = false;
+    lockNconfig();
+    bool ret=i2cRtos_stop(&m_channel->i2c);
+    unlock();
+    return ret;
 }
-
 void I2CDriver::stopSlave(void)
 {
-    lock();
-    m_channel->transfer.cmd = STOP;
-    m_channel->transfer.slv = true;
-    m_channel->transfer.adr = m_slaveAdr;
-    sendNwait();
+    m_modeSlave = true;
+    lockNconfig();
+    i2c_stop(&m_channel->i2c);
+    unlock();
 }
-
 int I2CDriver::receiveSlave(uint32_t timeout_ms)
 {
-    lock();
-    m_channel->transfer.cmd = RECEIVE;
-    m_channel->transfer.slv = true;
-    m_channel->transfer.adr = m_slaveAdr;
-    m_channel->transfer.tmout = timeout_ms;
-    return sendNwait();
+    m_modeSlave = true;
+    lockNconfig();
+    int ret = i2cRtos_slave_receive(&m_channel->i2c, timeout_ms);
+    unlock();
+    return ret;
 }
-
 int I2CDriver::readSlave(char* data, int length)
 {
-    lock();
-    m_channel->transfer.cmd = READ_SLV;
-    m_channel->transfer.slv = true;
-    m_channel->transfer.adr = m_slaveAdr;
-    m_channel->transfer.dta = data;
-    m_channel->transfer.len = length;
-    return sendNwait();
+    m_modeSlave = true;
+    lockNconfig();
+    int ret = i2cRtos_slave_read(&m_channel->i2c, data, length);
+    unlock();
+    return ret;
 }
-
 int I2CDriver::readSlave(void)
 {
-    lock();
-    m_channel->transfer.cmd = READ_BYTE;
-    m_channel->transfer.slv = true;
-    m_channel->transfer.adr = m_slaveAdr;
-    m_channel->transfer.ack = 1;
-    return sendNwait();
+    m_modeSlave = true;
+    lockNconfig();
+    int ret = i2cRtos_byte_read(&m_channel->i2c, 0);
+    unlock();
+    return ret;
 }
-
 int I2CDriver::writeSlave(const char *data, int length)
 {
-    lock();
-    m_channel->transfer.cmd = WRITE_SLV;
-    m_channel->transfer.slv = true;
-    m_channel->transfer.adr = m_slaveAdr;
-    m_channel->transfer.wdta = data;
-    m_channel->transfer.len = length;
-    return sendNwait();
+    m_modeSlave = true;
+    lockNconfig();
+    int ret = i2cRtos_slave_write(&m_channel->i2c, data, length);
+    unlock();
+    return ret;
 }
-
 int I2CDriver::writeSlave(int data)
 {
-    lock();
-    m_channel->transfer.cmd = WRITE_BYTE;
-    m_channel->transfer.slv = true;
-    m_channel->transfer.adr = m_slaveAdr;
-    m_channel->transfer.ack = data;
-    return sendNwait();
+    m_modeSlave = true;
+    lockNconfig();
+    int ret = i2cRtos_byte_write(&m_channel->i2c, data);
+    unlock();
+    return ret;
 }
 
 

--- a/I2CDriver.h	Fri May 10 07:34:24 2013 +0000
+++ b/I2CDriver.h	Fri May 10 20:38:35 2013 +0000
@@ -5,7 +5,6 @@
 
 #include "I2C.h"
 
-#include "Thread.h"
 #include "Mutex.h"
 
 namespace mbed
@@ -115,7 +114,7 @@
      *  general call address.
      */
     void addressSlave(int address) {
-        m_slaveAdr=address;
+        m_slaveAdr=(address & 0xff) | 1;
     }
 
     /** Checks to see if this I2C Slave has been addressed.
@@ -137,6 +136,7 @@
      *  @returns
      *       0 on success,
      *   non-0 otherwise
+     * ... no! instead it returns number of bytes read minus one ... weird, guess its a bug in the official lib
      */
     int readSlave(char *data, int length);
 
@@ -154,7 +154,7 @@
      *
      *  @returns
      *       0 on success,
-     *   non-0 otherwise
+     *   non-0 otherwise 
      */
     int writeSlave(const char *data, int length);
 
@@ -175,8 +175,10 @@
     ///Creates a stop condition on the I2C bus
     void stopSlave(void);
 
-    ///Creates a stop condition on the I2C bus
-    void stopMaster(void);
+    /// Creates a stop condition on the I2C bus
+    /// If unsccessful because someone on the bus holds the scl line down it returns "false" after 23µs 
+    /// In normal operation the stop shouldn't take longer than 12µs @ 100kHz and 3-4µs @ 400kHz. 
+    bool stopMaster(void);
 
     /// Wait until the i2c driver becomes available.
     ///
@@ -189,52 +191,30 @@
     void unlock();
 
 protected:
-    // commands sent from user to drive thread
-    enum Command {
-        START,
-        STOP,
-        READ_MST,
-        READ_MST_REG,
-        READ_SLV,
-        READ_BYTE,
-        WRITE_MST,
-        WRITE_SLV,
-        WRITE_BYTE,
-        RECEIVE
+    void config();
+    void lockNconfig() {
+        lock();
+        config();
+    }
+
+    // structure that holds I2C channels status
+    struct Channel {
+        rtos::Mutex mutex;
+        i2c_t i2c;
+        int freq;
+        int slaveAdr;
+        bool modeSlave;
     };
 
-    // data transfer struct for communication between user and driver thread
-    struct Transfer {
-        Command cmd;
-        int ret;
-        int freq;
-        int adr;
-        char* dta;
-        const char* wdta;
-        int len;
-        int ack;
-        bool rep;
-        uint8_t reg;
-        bool slv;
-        uint32_t tmout;
-        osThreadId caller;
-    };
+    // curren i2c configuration of this driver interface
+    int m_freq;
+    int m_slaveAdr;
+    bool m_modeSlave;
 
-    // structure that holds handles/locks for accessing the I2C channels
-    struct Channel {
-        osThreadId driver;
-        rtos::Mutex  mutex;
-        volatile Transfer transfer;
-    };
-
-    // current frequency setting
-    int m_freq;
-    // current slave address setting
-    int m_slaveAdr;
-    // prio of current caller thread
+    // id and prio of current caller thread
+    osThreadId m_callerID;
     osPriority m_callerPrio;
-    // ID of current caller thread
-    osThreadId m_callerID;
+    
 
     // i2c driver prio
     static const osPriority c_drvPrio = osPriorityRealtime;
@@ -245,14 +225,9 @@
     // static storage for the I2C channel access objects
     static Channel* s_channels[2];
 
-    // i2c channel object of this driver interface, in fact just pointer
+    // i2c channel object of this driver interface, in fact just a pointer
     /// to one of the entries in s_channels
     Channel* m_channel;
-
-    // the driver thread function
-    static void threadFun(void const *args);
-
-    int sendNwait();
 };
 }
 #endif

--- a/I2CDriverTest03.h	Fri May 10 07:34:24 2013 +0000
+++ b/I2CDriverTest03.h	Fri May 10 20:38:35 2013 +0000
@@ -1,173 +1,97 @@
 #include "mbed.h"
 #include "rtos.h"
 #include "I2CMasterRtos.h"
-#include "stdint.h"
+#include "I2CSlaveRtos.h"
 
-const int dataReadySig = 1<<5;
-osThreadId mainThreadID = 0;
-char data[64];
-int16_t fifo[16];
-const int i2cAdr = 0x68<<1;
-int fifoAdr = 0x72;
+const int freq = 400000;
+const int adr = 42<<1;
+const int len=34;
+const char mstMsg[len]="We are mbed, resistance is futile";
+const char slvMsg[len]="Fine with me, let's get addicted ";
 
-//Serial pc(USBTX, USBRX);
-
-void configMPU6050(I2CMasterRtos& i2c);
-void config(I2CMasterRtos& i2c);
+static void slvRxMsg(I2CSlaveRtos& slv)
+{
+    char rxMsg[len];
+    memset(rxMsg,0,len);
+    if ( slv.receive() == I2CSlave::WriteAddressed ) {
+        int cnt=0;
+        while(cnt<len) rxMsg[cnt++]=slv.read();
+        slv.stop(); // stop sretching low level of scl
+        printf("thread %x received message (sz=%d) as i2c slave: '%s'\n",Thread::gettid(),cnt,rxMsg);
+    } else
+        printf("Ouch slv rx failure\n");
+}
 
+static void slvTxMsg(I2CSlaveRtos& slv)
+{
+    if ( slv.receive()==I2CSlave::ReadAddressed) {
+        int cnt=0;
+        while(cnt<len && slv.write(slvMsg[cnt++]));
+        slv.stop(); // stop sretching low level of scl
+    } else
+        printf("Ouch slv tx failure\n");
+}
 
-void dataReadyIsr()
+static void mstTxMsg(I2CMasterRtos& mst)
 {
-    osSignalSet(mainThreadID, dataReadySig);
+    mst.start();
+    if(!mst.write(adr & 0xfe))printf("adr+W not acked\n");
+    int cnt=0;
+    while(cnt<len && mst.write(mstMsg[cnt++]));
+    // give the slave a chance to stop stretching scl to low, otherwise we will busy wait for the stop forever
+    while(!mst.stop())Thread::wait(1);
 }
 
-void readModWrite(I2CMasterRtos& i2c, uint8_t reg, uint8_t dta)
+static void mstRxMsg(I2CMasterRtos& mst)
 {
+    char rxMsg[len];
+    memset(rxMsg,0,len);
     
-    char rd1;
-    int rStat1 = i2c.read(i2cAdr, reg, &rd1, 1);
-    char data[2];
-    data[0]=(char)reg;
-    data[1]=(char)dta;
-    char rd2;
-    int wStat = i2c.write(i2cAdr, data, 2);
-    osDelay(500);
-    int rStat2 = i2c.read(i2cAdr, reg, &rd2, 1);
-    printf("%2d%2d%2d  %2x <- %2x  => %2x -> %2x \n", rStat1, wStat, rStat2, reg, dta, rd1, rd2);
+    mst.lock(); // no special reason, just a test
+    mst.start();
+    if(!mst.write(adr | 0x01))printf("adr+R not acked\n");
+    int cnt=0;
+    while(cnt<len-1) rxMsg[cnt++]=mst.read(1);
+    mst.unlock();
+    rxMsg[cnt++]=mst.read(0);
+    // give the slave a chance to stop stretching scl to low, otherwise we will busy wait for the stop forever
+    while(!mst.stop())Thread::wait(1);
+    printf("thread %x received message (sz=%d) as i2c master: '%s'\n",Thread::gettid(),cnt,rxMsg);
 }
 
+static void channel1(void const *args)
+{
+    I2CMasterRtos mst(p9,p10,freq);
+    I2CSlaveRtos slv(p9,p10,freq,adr);
+    while(1) {
+        slvRxMsg(slv);
+        slvTxMsg(slv);
+        Thread::wait(100);
+        mstTxMsg(mst);
+        Thread::wait(100);
+        mstRxMsg(mst);
+    }
+}
+
+void channel2(void const *args)
+{
+    I2CMasterRtos mst(p28,p27,freq);
+    I2CSlaveRtos slv(p28,p27,freq,adr);
+    while(1) {
+        Thread::wait(100);
+        mstTxMsg(mst);
+        Thread::wait(100);
+        mstRxMsg(mst);
+        slvRxMsg(slv);
+        slvTxMsg(slv);
+    }
+}
 
 int doit()
 {
-    //pc.baud(115200);
-    mainThreadID = osThreadGetId();
-
-    I2CMasterRtos i2c(p28, p27,400000);
-    osDelay(500);
-
-    printf("Initialize ... \n");
-    config(i2c);
-
-    printf("Action!\n");
-
-    InterruptIn dataReadyIrq(p8);
-    dataReadyIrq.mode(PullNone);
-    dataReadyIrq.rise(&dataReadyIsr);
-
-    /*
-    data[0]=0x6a;   // pwr 1 reg
-    data[1]=(1<<6)|(1<<2); // fifo on
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x38;   // irq conf  reg
-    data[1]=1;      // irq on data ready
-    i2c.write(i2cAdr,data,2,1);
-    */
-    //fifoAdr = 0x3b;
-    char devNull;
-    while(1) {
-        osSignalWait(dataReadySig, 1000); // osWaitForever
-        i2c.read(i2cAdr,fifoAdr,data,2);
-        i2c.read(i2cAdr,fifoAdr+2,data+2,12);
-        i2c.read(i2cAdr,0x3a,&devNull,1);
-        for(int i=0; i<7; i++) {
-            fifo[i] = (data[2*i]<<8) | data[2*i+1];
-            printf("%8d",fifo[i]);
-        }
-        printf("     %x\n",devNull);
-
-    }
+    Thread selftalk01(channel1,0);
+    Thread selftalk02(channel2,0);
+    Thread::wait(5000);
     return 0;
 }
 
-static void config(I2CMasterRtos& i2c)
-{
-    uint8_t ncfg=32;
-    uint8_t regs[ncfg];
-    uint8_t vals[ncfg];
-    int cnt=0;
-    regs[cnt]=0x6b;
-    vals[cnt++]=(1<<7); // pwr 1 reg //: device reset
-    regs[cnt]=0x6b;
-    vals[cnt++]=1; // pwr 1 reg // clock from x gyro all pwr sav modes off
-    regs[cnt]=0x19;
-    vals[cnt++]=199;  // sample rate divider reg  // sapmle rate = gyro rate / (1+x)
-    regs[cnt]=0x1a;
-    vals[cnt++]=1;// conf  reg // no ext frame sync / dig low pass set to 1 => 1kHz Sampling with ~200Hz bandwidth DLPF
-    regs[cnt]=0x1b;
-    vals[cnt++]=0;// gyro conf  reg // no test mode and gyro range 250°/s
-    regs[cnt]=0x1c;
-    vals[cnt++]=0;// accl conf  reg // no test mode and accl range 2g
-    regs[cnt]=0x23;
-    vals[cnt++]=0xf<<3;// fifo conf  reg // accl + all gyro -> fifo
-    regs[cnt]=0x37;
-    vals[cnt++]=(0<<7)|(0<<6)|(0<<5)|(0<<4); // irq conf  reg // act high | 0:pupu 1:opnDrn| pulse | clear on any read
-    regs[cnt]=0x38;
-    vals[cnt++]=1|(1<<4); // irq conf  reg // irq on data ready
-    regs[cnt]=0x6a;
-    vals[cnt++]=(1<<2); // pwr 1 reg // fifo reset
-    regs[cnt]=0x6a;
-    vals[cnt++]=(1<<6); // pwr 1 reg // fifo on
-
-    /*
-    readModWrite(i2c, regs[0], vals[0]);
-    char reset=0xff;
-    while(reset&(1<<7)) {
-        osDelay(100);
-        i2c.read(i2cAdr,0x6b,&reset,1,1);
-    }
-    */
-    for(int i=0; i<cnt; i++)
-        readModWrite(i2c, regs[i], vals[i]);
-}
-
-static void configMPU6050(I2CMasterRtos& i2c)
-{
-
-    data[0]=0x6b;   // pwr 1 reg
-    data[1]=1<<7;   // device reset
-    i2c.write(i2cAdr,data,2,1);
-    char reset=0xff;
-    while(reset&(1<<7)) {
-        osDelay(100);
-        i2c.read(i2cAdr,0x6b,&reset,1,1);
-    }
-
-    data[0]=0x19;   // sample rate divider reg
-    data[1]=99;    // sapmle rate = gyro rate / (1+x)
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x1a;   // conf  reg
-    data[1]=1;      // no ext frame sync / dig low pass set to 1 => 1kHz Sampling with ~200Hz bandwidth DLPF
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x1b;   // gyro conf  reg
-    data[1]=0;      // no test mode and gyro range 250°/s
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x1c;   // accl conf  reg
-    data[1]=0;      // no test mode and accl range 2g
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x23;   // fifo conf  reg
-    data[1]=0xf<<3; // accl + all gyro -> fifo
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x37;   // irq conf  reg
-    data[1]=(1<<7)|(0<<6)|(0<<5)|(1<<4); // act high | pupu | pulse | clear on any read
-    i2c.write(i2cAdr,data,2,1);
-
-    /*
-    data[0]=0x38;   // irq conf  reg
-    data[1]=1;      // irq on data ready
-    i2c.write(i2cAdr,data,2,1);
-
-    data[0]=0x6a;   // pwr 1 reg
-    data[1]=(1<<6); // fifo on
-    i2c.write(i2cAdr,data,2,1);
-    */
-    data[0]=0x6b;   // pwr 1 reg
-    data[1]=1;      // clock from x gyro all pwr sav modes off
-    i2c.write(i2cAdr,data,2,1);
-}
-

--- a/I2CDriverTest04.h	Fri May 10 07:34:24 2013 +0000
+++ b/I2CDriverTest04.h	Fri May 10 20:38:35 2013 +0000
@@ -63,7 +63,7 @@
 #elif defined(TARGET_LPC11U24)
     const int nTest=5;
     const int freq[nTest]=  {1e5,   1e5,    4e5,   4e5,    4e5    };
-    const int len[nTest]=   {1,     4,      1,      6,     16};
+    const int len[nTest]=   {1,     6,      1,      6,     32};
 #endif
     for(int i=0; i<nTest; ++i) {
         g_freq = freq[i];

--- a/I2CMasterRtos.h	Fri May 10 07:34:24 2013 +0000
+++ b/I2CMasterRtos.h	Fri May 10 20:38:35 2013 +0000
@@ -112,14 +112,29 @@
     /** Creates a start condition on the I2C bus
      */
 
-    void startMaster(void) {
+    void start(void) {
         m_drv.startMaster();
     }
 
-    /** Creates a stop condition on the I2C bus
-     */
-    void stop(void) {
-        m_drv.stopMaster();
+    /// Creates a stop condition on the I2C bus
+    /// If unsccessful because someone on the bus holds the scl line down it returns "false" after 23µs 
+    /// In normal operation the stop shouldn't take longer than 12µs @ 100kHz and 3-4µs @ 400kHz. 
+    bool stop(void) {
+        return m_drv.stopMaster();
+    }
+
+    /// Wait until the interface becomes available.
+    ///
+    /// Useful if you want to run a sequence of command without interrution by another thread.
+    /// There's no need to call this function for running single request, because all driver functions
+    /// will lock the device for exclusive access automatically.
+    void lock() {
+        m_drv.lock();
+    }
+
+    /// Unlock the interface that has previously been locked by the same thread.
+    void unlock() {
+        m_drv.unlock();
     }
 
 };

--- a/I2CSlaveRtos.h	Fri May 10 07:34:24 2013 +0000
+++ b/I2CSlaveRtos.h	Fri May 10 20:38:35 2013 +0000
@@ -60,6 +60,7 @@
      *  @returns
      *       0 on success,
      *   non-0 otherwise
+     * ... no! instead it returns number of bytes read minus one ... weird, guess its a bug in the official lib
      */
     int read(char *data, int length) {
         return m_drv.readSlave(data, length);
@@ -112,9 +113,25 @@
 
     /** Reset the I2C slave back into the known ready receiving state.
      */
-    void stop(void){
+    void stop(void) {
         m_drv.stopSlave();
     }
+
+
+    /// Wait until the interface becomes available.
+    ///
+    /// Useful if you want to run a sequence of command without interrution by another thread.
+    /// There's no need to call this function for running single request, because all driver functions
+    /// will lock the device for exclusive access automatically.
+    void lock() {
+        m_drv.lock();
+    }
+
+    /// Unlock the interface that has previously been locked by the same thread.
+    void unlock() {
+        m_drv.unlock();
+    }
+
 };
 }
 

--- a/i2cRtos_api.c	Fri May 10 07:34:24 2013 +0000
+++ b/i2cRtos_api.c	Fri May 10 20:38:35 2013 +0000
@@ -2,16 +2,24 @@
 
 #if DEVICE_I2C
 
+#include "us_ticker_api.h"
 #include "cmsis_os.h"
 #include "error.h"
 
+#if defined(TARGET_LPC1768) || defined(TARGET_LPC2368)
 #define I2C_CONSET(x)       (x->i2c->I2CONSET)
 #define I2C_CONCLR(x)       (x->i2c->I2CONCLR)
 #define I2C_STAT(x)         (x->i2c->I2STAT)
 #define I2C_DAT(x)          (x->i2c->I2DAT)
+#elif defined(TARGET_LPC11U24)
+#define I2C_CONSET(x)       (x->i2c->CONSET)
+#define I2C_CONCLR(x)       (x->i2c->CONCLR)
+#define I2C_STAT(x)         (x->i2c->STAT)
+#define I2C_DAT(x)          (x->i2c->DAT)
+#endif
 
-//#include "gpio_api.h"
-//static gpio_t gpio[2]; // evillive
+#include "gpio_api.h"
+static gpio_t gpio[2]; // evillive
 
 enum I2cIsrCmd {
     readMst,
@@ -126,12 +134,14 @@
         NVIC_DisableIRQ(isrIrqSem[ch].irq);
     }
 }
+#if defined(TARGET_LPC1768) || defined(TARGET_LPC2368)
 static void i2cRtos_isr_ch0()
 {
     //gpio_write(&gpio[0], 1);
     i2cRtos_isr(0);
     //gpio_write(&gpio[0], 0);
 }
+#endif
 static void i2cRtos_isr_ch1()
 {
     //gpio_write(&gpio[1], 1);
@@ -249,6 +259,19 @@
 }
 
 
+inline int i2cRtos_stop(i2c_t *obj) {
+    i2c_conset(obj, 0, 1, 0, 0);
+    i2c_clear_SI(obj);
+    
+    uint32_t t0=us_ticker_read();
+    uint32_t dt=0;
+    while((I2C_CONSET(obj) & (1 << 4)) && dt<23){
+        dt = us_ticker_read() - t0;
+    }
+    return dt<23;
+}
+
+
 #if DEVICE_I2CSLAVE
 
 
@@ -306,7 +329,7 @@
 // setup semaphores and hook in ISRs
 void i2cRtos_init(i2c_t *obj, PinName sda, PinName scl)
 {
-    /*
+    
     static int called=0;
     if(!called) {
         gpio_init(&gpio[0], p15, PIN_OUTPUT);
@@ -315,7 +338,7 @@
     called = 1;
     gpio_write(&gpio[0], 0);
     gpio_write(&gpio[1], 0);
-    */
+    
     i2c_init(obj,sda,scl);
     uint32_t ch = i2c_get_channel(obj);
 #if defined(TARGET_LPC1768) || defined(TARGET_LPC2368)

--- a/i2cRtos_api.h	Fri May 10 07:34:24 2013 +0000
+++ b/i2cRtos_api.h	Fri May 10 20:38:35 2013 +0000
@@ -29,6 +29,7 @@
     int  i2cRtos_write(i2c_t *obj, int address, const char *data, int length, int stop);
     int  i2cRtos_byte_read(i2c_t *obj, int last);
     int  i2cRtos_byte_write(i2c_t *obj, int data);
+    int  i2cRtos_stop(i2c_t *obj);
 
 #if DEVICE_I2CSLAVE
     int  i2cRtos_slave_receive(i2c_t *obj, uint32_t tmOut);