uart_8c-source.html

avr应用测试程序

00142         {
00143             <span class="comment">// get byte from beginning of buffer</span>
00144             *rxData = <a class="code" href="group__buffer.html#ga2">bufferGetFromFront</a>(&amp;uartRxBuffer);
00145             <span class="keywordflow">return</span> TRUE;
00146         }
00147         <span class="keywordflow">else</span>
00148         {
00149             <span class="comment">// no data</span>
00150             <span class="keywordflow">return</span> FALSE;
00151         }
00152     }
00153     <span class="keywordflow">else</span>
00154     {
00155         <span class="comment">// no buffer</span>
00156         <span class="keywordflow">return</span> FALSE;
00157     }
00158 }
00159 
00160 <span class="comment">// flush all data out of the receive buffer</span>
<a name="l00161"></a><a class="code" href="group__uart.html#ga10">00161</a> <span class="keywordtype">void</span> <a class="code" href="group__uart.html#ga10">uartFlushReceiveBuffer</a>(<span class="keywordtype">void</span>)
00162 {
00163     <span class="comment">// flush all data from receive buffer</span>
00164     <span class="comment">//bufferFlush(&amp;uartRxBuffer);</span>
00165     <span class="comment">// same effect as above</span>
00166     uartRxBuffer.<a class="code" href="structstruct__cBuffer.html#o2">datalength</a> = 0;
00167 }
00168 
00169 <span class="comment">// return true if uart receive buffer is empty</span>
<a name="l00170"></a><a class="code" href="group__uart.html#ga9">00170</a> u08 <a class="code" href="group__uart.html#ga9">uartReceiveBufferIsEmpty</a>(<span class="keywordtype">void</span>)
00171 {
00172     <span class="keywordflow">if</span>(uartRxBuffer.<a class="code" href="structstruct__cBuffer.html#o2">datalength</a> == 0)
00173     {
00174         <span class="keywordflow">return</span> TRUE;
00175     }
00176     <span class="keywordflow">else</span>
00177     {
00178         <span class="keywordflow">return</span> FALSE;
00179     }
00180 }
00181 
00182 <span class="comment">// add byte to end of uart Tx buffer</span>
<a name="l00183"></a><a class="code" href="group__uart.html#ga11">00183</a> u08 <a class="code" href="group__uart.html#ga11">uartAddToTxBuffer</a>(u08 data)
00184 {
00185     <span class="comment">// add data byte to the end of the tx buffer</span>
00186     <span class="keywordflow">return</span> <a class="code" href="group__buffer.html#ga5">bufferAddToEnd</a>(&amp;uartTxBuffer, data);
00187 }
00188 
00189 <span class="comment">// start transmission of the current uart Tx buffer contents</span>
<a name="l00190"></a><a class="code" href="group__uart.html#ga12">00190</a> <span class="keywordtype">void</span> <a class="code" href="group__uart.html#ga12">uartSendTxBuffer</a>(<span class="keywordtype">void</span>)
00191 {
00192     <span class="comment">// turn on buffered transmit</span>
00193     <a class="code" href="uart_8c.html#a1">uartBufferedTx</a> = TRUE;
00194     <span class="comment">// send the first byte to get things going by interrupts</span>
00195     <a class="code" href="group__uart.html#ga6">uartSendByte</a>(<a class="code" href="group__buffer.html#ga2">bufferGetFromFront</a>(&amp;uartTxBuffer));
00196 }
00197 <span class="comment">/*</span>
00198 <span class="comment">// transmit nBytes from buffer out the uart</span>
00199 <span class="comment">u08 uartSendBuffer(char *buffer, u16 nBytes)</span>
00200 <span class="comment">{</span>
00201 <span class="comment">    register u08 first;</span>
00202 <span class="comment">    register u16 i;</span>
00203 <span class="comment"></span>
00204 <span class="comment">    // check if there's space (and that we have any bytes to send at all)</span>
00205 <span class="comment">    if((uartTxBuffer.datalength + nBytes &lt; uartTxBuffer.size) &amp;&amp; nBytes)</span>
00206 <span class="comment">    {</span>
00207 <span class="comment">        // grab first character</span>
00208 <span class="comment">        first = *buffer++;</span>
00209 <span class="comment">        // copy user buffer to uart transmit buffer</span>
00210 <span class="comment">        for(i = 0; i &lt; nBytes-1; i++)</span>
00211 <span class="comment">        {</span>
00212 <span class="comment">            // put data bytes at end of buffer</span>
00213 <span class="comment">            bufferAddToEnd(&amp;uartTxBuffer, *buffer++);</span>
00214 <span class="comment">        }</span>
00215 <span class="comment"></span>
00216 <span class="comment">        // send the first byte to get things going by interrupts</span>
00217 <span class="comment">        uartBufferedTx = TRUE;</span>
00218 <span class="comment">        uartSendByte(first);</span>
00219 <span class="comment">        // return success</span>
00220 <span class="comment">        return TRUE;</span>
00221 <span class="comment">    }</span>
00222 <span class="comment">    else</span>
00223 <span class="comment">    {</span>
00224 <span class="comment">        // return failure</span>
00225 <span class="comment">        return FALSE;</span>
00226 <span class="comment">    }</span>
00227 <span class="comment">}</span>
00228 <span class="comment">*/</span>
00229 <span class="comment">// UART Transmit Complete Interrupt Handler</span>
00230 <a class="code" href="group__uart.html#ga17">UART_INTERRUPT_HANDLER</a>(SIG_UART_TRANS)
00231 {
00232     <span class="comment">// check if buffered tx is enabled</span>
00233     <span class="keywordflow">if</span>(<a class="code" href="uart_8c.html#a1">uartBufferedTx</a>)
00234     {
00235         <span class="comment">// check if there's data left in the buffer</span>
00236         <span class="keywordflow">if</span>(uartTxBuffer.<a class="code" href="structstruct__cBuffer.html#o2">datalength</a>)
00237         {
00238             <span class="comment">// send byte from top of buffer</span>
00239             outb(UDR, <a class="code" href="group__buffer.html#ga2">bufferGetFromFront</a>(&amp;uartTxBuffer));
00240         }
00241         <span class="keywordflow">else</span>
00242         {
00243             <span class="comment">// no data left</span>
00244             <a class="code" href="uart_8c.html#a1">uartBufferedTx</a> = FALSE;
00245             <span class="comment">// return to ready state</span>
00246             <a class="code" href="uart_8c.html#a0">uartReadyTx</a> = TRUE;
00247         }
00248     }
00249     <span class="keywordflow">else</span>
00250     {
00251         <span class="comment">// we're using single-byte tx mode</span>
00252         <span class="comment">// indicate transmit complete, back to ready</span>
00253         <a class="code" href="uart_8c.html#a0">uartReadyTx</a> = TRUE;
00254     }
00255 }
00256 
00257 <span class="comment">// UART Receive Complete Interrupt Handler</span>
00258 <a class="code" href="group__uart.html#ga17">UART_INTERRUPT_HANDLER</a>(SIG_UART_RECV)
00259 {
00260     u08 c;
00261     
00262     <span class="comment">// get received char</span>
00263     c = inb(UDR);
00264 
00265     <span class="comment">// if there's a user function to handle this receive event</span>
00266     <span class="keywordflow">if</span>(UartRxFunc)
00267     {
00268         <span class="comment">// call it and pass the received data</span>
00269         UartRxFunc(c);
00270     }
00271     <span class="keywordflow">else</span>
00272     {
00273         <span class="comment">// otherwise do default processing</span>
00274         <span class="comment">// put received char in buffer</span>
00275         <span class="comment">// check if there's space</span>
00276         <span class="keywordflow">if</span>( !<a class="code" href="group__buffer.html#ga5">bufferAddToEnd</a>(&amp;uartRxBuffer, c) )
00277         {
00278             <span class="comment">// no space in buffer</span>
00279             <span class="comment">// count overflow</span>
00280             <a class="code" href="uart_8c.html#a4">uartRxOverflow</a>++;
00281         }
00282     }
00283 }
</pre></div><hr size="1"><address style="align: right;"><small>Generated on Sun Oct 29 03:41:08 2006 for Procyon AVRlib by&nbsp;
<a href="http://www.doxygen.org/index.html">
<img src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.4.2 </small></address>
</body>
</html>