00211     <span class="comment">// save data</span>00212     I2cDeviceAddrRW = (deviceAddr &amp; 0xFE);  <span class="comment">// RW cleared: write operation</span>00213     <span class="keywordflow">for</span>(i=0; i&lt;length; i++)00214         I2cSendData[i] = *data++;00215     I2cSendDataIndex = 0;00216     I2cSendDataLength = length;00217     <span class="comment">// send start condition</span>00218     <a class="code" href="i2c_8c.html#a15">i2cSendStart</a>();00219 }00220 <a name="l00221"></a><a class="code" href="i2c_8h.html#a23">00221</a> <span class="keywordtype">void</span> <a class="code" href="i2c_8h.html#a23">i2cMasterReceive</a>(u08 deviceAddr, u08 length, u08* data)00222 {00223     u08 i;00224     <span class="comment">// wait for interface to be ready</span>00225     <span class="keywordflow">while</span>(I2cState);00226     <span class="comment">// set state</span>00227     I2cState = I2C_MASTER_RX;00228     <span class="comment">// save data</span>00229     I2cDeviceAddrRW = (deviceAddr|0x01);    <span class="comment">// RW set: read operation</span>00230     I2cReceiveDataIndex = 0;00231     I2cReceiveDataLength = length;00232     <span class="comment">// send start condition</span>00233     <a class="code" href="i2c_8c.html#a15">i2cSendStart</a>();00234     <span class="comment">// wait for data</span>00235     <span class="keywordflow">while</span>(I2cState);00236     <span class="comment">// return data</span>00237     <span class="keywordflow">for</span>(i=0; i&lt;length; i++)00238         *data++ = I2cReceiveData[i];00239 }00240 <a name="l00241"></a><a class="code" href="i2c_8h.html#a24">00241</a> u08 <a class="code" href="i2c_8h.html#a24">i2cMasterSendNI</a>(u08 deviceAddr, u08 length, u08* data)00242 {00243     u08 retval = I2C_OK;00244 00245     <span class="comment">// disable TWI interrupt</span>00246     cbi(TWCR, TWIE);00247 00248     <span class="comment">// send start condition</span>00249     <a class="code" href="i2c_8c.html#a15">i2cSendStart</a>();00250     <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00251 00252     <span class="comment">// send device address with write</span>00253     <a class="code" href="i2c_8h.html#a18">i2cSendByte</a>( deviceAddr &amp; 0xFE );00254     <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00255 00256     <span class="comment">// check if device is present and live</span>00257     <span class="keywordflow">if</span>( inb(TWSR) == TW_MT_SLA_ACK)00258     {00259         <span class="comment">// send data</span>00260         <span class="keywordflow">while</span>(length)00261         {00262             <a class="code" href="i2c_8h.html#a18">i2cSendByte</a>( *data++ );00263             <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00264             length--;00265         }00266     }00267     <span class="keywordflow">else</span>00268     {00269         <span class="comment">// device did not ACK it's address,</span>00270         <span class="comment">// data will not be transferred</span>00271         <span class="comment">// return error</span>00272         retval = I2C_ERROR_NODEV;00273     }00274 00275     <span class="comment">// transmit stop condition</span>00276     <span class="comment">// leave with TWEA on for slave receiving</span>00277     <a class="code" href="i2c_8c.html#a16">i2cSendStop</a>();00278     <span class="keywordflow">while</span>( !(inb(TWCR) &amp; BV(TWSTO)) );00279 00280     <span class="comment">// enable TWI interrupt</span>00281     sbi(TWCR, TWIE);00282 00283     <span class="keywordflow">return</span> retval;00284 }00285 <a name="l00286"></a><a class="code" href="i2c_8h.html#a25">00286</a> u08 <a class="code" href="i2c_8h.html#a25">i2cMasterReceiveNI</a>(u08 deviceAddr, u08 length, u08 *data)00287 {00288     u08 retval = I2C_OK;00289 00290     <span class="comment">// disable TWI interrupt</span>00291     cbi(TWCR, TWIE);00292 00293     <span class="comment">// send start condition</span>00294     <a class="code" href="i2c_8c.html#a15">i2cSendStart</a>();00295     <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00296 00297     <span class="comment">// send device address with read</span>00298     <a class="code" href="i2c_8h.html#a18">i2cSendByte</a>( deviceAddr | 0x01 );00299     <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00300 00301     <span class="comment">// check if device is present and live</span>00302     <span class="keywordflow">if</span>( inb(TWSR) == TW_MR_SLA_ACK)00303     {00304         <span class="comment">// accept receive data and ack it</span>00305         <span class="keywordflow">while</span>(length &gt; 1)00306         {00307             <a class="code" href="i2c_8h.html#a19">i2cReceiveByte</a>(TRUE);00308             <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00309             *data++ = <a class="code" href="i2c_8c.html#a20">i2cGetReceivedByte</a>();00310             <span class="comment">// decrement length</span>00311             length--;00312         }00313 00314         <span class="comment">// accept receive data and nack it (last-byte signal)</span>00315         <a class="code" href="i2c_8h.html#a19">i2cReceiveByte</a>(FALSE);00316         <a class="code" href="i2c_8c.html#a17">i2cWaitForComplete</a>();00317         *data++ = <a class="code" href="i2c_8c.html#a20">i2cGetReceivedByte</a>();00318     }00319     <span class="keywordflow">else</span>00320     {00321         <span class="comment">// device did not ACK it's address,</span>00322         <span class="comment">// data will not be transferred</span>00323         <span class="comment">// return error</span>00324         retval = I2C_ERROR_NODEV;00325     }00326 00327     <span class="comment">// transmit stop condition</span>00328     <span class="comment">// leave with TWEA on for slave receiving</span>00329     <a class="code" href="i2c_8c.html#a16">i2cSendStop</a>();00330 00331     <span class="comment">// enable TWI interrupt</span>00332     sbi(TWCR, TWIE);00333 00334     <span class="keywordflow">return</span> retval;00335 }00336 <span class="comment">/*</span>00337 <span class="comment">void i2cMasterTransferNI(u08 deviceAddr, u08 sendlength, u08* senddata, u08 receivelength, u08* receivedata)</span>00338 <span class="comment">{</span>00339 <span class="comment">    // disable TWI interrupt</span>00340 <span class="comment">    cbi(TWCR, TWIE);</span>00341 <span class="comment"></span>00342 <span class="comment">    // send start condition</span>00343 <span class="comment">    i2cSendStart();</span>00344 <span class="comment">    i2cWaitForComplete();</span>00345 <span class="comment"></span>00346 <span class="comment">    // if there's data to be sent, do it</span>00347 <span class="comment">    if(sendlength)</span>00348 <span class="comment">    {</span>00349 <span class="comment">        // send device address with write</span>00350 <span class="comment">        i2cSendByte( deviceAddr &amp; 0xFE );</span>00351 <span class="comment">        i2cWaitForComplete();</span>00352 <span class="comment">        </span>00353 <span class="comment">        // send data</span>00354 <span class="comment">        while(sendlength)</span>00355 <span class="comment">        {</span>00356 <span class="comment">            i2cSendByte( *senddata++ );</span>00357 <span class="comment">            i2cWaitForComplete();</span>00358 <span class="comment">            sendlength--;</span>00359 <span class="comment">        }</span>00360 <span class="comment">    }</span>00361 <span class="comment"></span>00362 <span class="comment">    // if there's data to be received, do it</span>00363 <span class="comment">    if(receivelength)</span>00364 <span class="comment">    {</span>00365 <span class="comment">        // send repeated start condition</span>00366 <span class="comment">        i2cSendStart();</span>00367 <span class="comment">        i2cWaitForComplete();</span>00368 <span class="comment"></span>00369 <span class="comment">        // send device address with read</span>00370 <span class="comment">        i2cSendByte( deviceAddr | 0x01 );</span>00371 <span class="comment">        i2cWaitForComplete();</span>00372 <span class="comment"></span>00373 <span class="comment">        // accept receive data and ack it</span>00374 <span class="comment">        while(receivelength &gt; 1)</span>00375 <span class="comment">        {</span>00376 <span class="comment">            i2cReceiveByte(TRUE);</span>00377 <span class="comment">            i2cWaitForComplete();</span>00378 <span class="comment">            *receivedata++ = i2cGetReceivedByte();</span>00379 <span class="comment">            // decrement length</span>00380 <span class="comment">            receivelength--;</span>00381 <span class="comment">        }</span>00382 <span class="comment"></span>00383 <span class="comment">        // accept receive data and nack it (last-byte signal)</span>00384 <span class="comment">        i2cReceiveByte(TRUE);</span>00385 <span class="comment">        i2cWaitForComplete();</span>00386 <span class="comment">        *receivedata++ = i2cGetReceivedByte();</span>00387 <span class="comment">    }</span>00388 <span class="comment">    </span>00389 <span class="comment">    // transmit stop condition</span>00390 <span class="comment">    // leave with TWEA on for slave receiving</span>00391 <span class="comment">    i2cSendStop();</span>00392 <span class="comment">    while( !(inb(TWCR) &amp; BV(TWSTO)) );</span>00393 <span class="comment"></span>00394 <span class="comment">    // enable TWI interrupt</span>00395 <span class="comment">    sbi(TWCR, TWIE);</span>00396 <span class="comment">}</span>00397 <span class="comment">*/</span>00398 <span class="comment"></span>00399 <span class="comment">//! I2C (TWI) interrupt service routine</span><a name="l00400"></a><a class="code" href="i2c_8c.html#a26">00400</a> <span class="comment"></span><a class="code" href="a2d_8c.html#a10">SIGNAL</a>(SIG_2WIRE_SERIAL)00401 {00402     <span class="comment">// read status bits</span>00403     u08 status = inb(TWSR) &amp; TWSR_STATUS_MASK;00404 00405     <span class="keywordflow">switch</span>(status)00406     {00407     <span class="comment">// Master General</span>00408     <span class="keywordflow">case</span> TW_START:                      <span class="comment">// 0x08: Sent start condition</span>00409     <span class="keywordflow">case</span> TW_REP_START:                  <span class="comment">// 0x10: Sent repeated start condition</span>00410 <span class="preprocessor">        #ifdef I2C_DEBUG</span>00411 <span class="preprocessor"></span>        <a class="code" href="rprintf_8h.html#a6">rprintfInit</a>(uart1AddToTxBuffer);00412         rprintf(<span class="stringliteral">"I2C: M-&gt;START\r\n"</span>);00413         <a class="code" href="rprintf_8h.html#a6">rprintfInit</a>(uart1SendByte);00414 <span class="preprocessor">        #endif</span>00415 <span class="preprocessor"></span>        <span class="comment">// send device address</span>00416         <a class="code" href="i2c_8h.html#a18">i2cSendByte</a>(I2cDeviceAddrRW);00417         <span class="keywordflow">break</span>;00418     00419     <span class="comment">// Master Transmitter &amp; Receiver status codes</span>00420     <span class="keywordflow">case</span> TW_MT_SLA_ACK:                 <span class="comment">// 0x18: Slave address acknowledged</span>00421     <span class="keywordflow">case</span> TW_MT_DATA_ACK:                <span class="comment">// 0x28: Data acknowledged</span>00422 <span class="preprocessor">        #ifdef I2C_DEBUG</span>00423 <span class="preprocessor"></span>        <a class="code" href="rprintf_8h.html#a6">rprintfInit</a>(uart1AddToTxBuffer);00424         rprintf(<span class="stringliteral">"I2C: MT-&gt;SLA_ACK or DATA_ACK\r\n"</span>);00425         <a class="code" href="rprintf_8h.html#a6">rprintfInit</a>(uart1SendByte);00426 <span class="preprocessor">        #endif</span>00427 <span class="preprocessor"></span>        <span class="keywordflow">if</span>(I2cSendDataIndex &lt; I2cSendDataLength)