ax88796_8c-source.html

单片机的软件

00230 
00231     <span class="keywordflow">if</span>(ax88796Read(GPI) &amp; I_SPD)        <span class="comment">// check PHY speed setting</span>
00232         tcrFduFlag = FDU;               <span class="comment">// if 100base, do full duplex</span>
00233     <span class="keywordflow">else</span>
00234         tcrFduFlag = 0;                 <span class="comment">// if 10base, do half duplex</span>
00235         
00236     ax88796Write(TCR,(tcrFduFlag|TCR_INIT));
00237 
00238     ax88796Write(GPOC,MPSEL);           <span class="comment">// select media interface</span>
00239   
00240     ax88796Write(TPSR,TXSTART_INIT);
00241 
00242     ax88796Write(CR,(RD2|STOP));
00243     ax88796Write(DCR,DCR_INIT);
00244     ax88796Write(CR,(RD2|START));
00245     ax88796Write(ISR,0xFF);
00246     ax88796Write(IMR,IMR_INIT);
00247     ax88796Write(TCR,(tcrFduFlag|TCR_INIT));
00248 
00249     <span class="comment">//test</span>
00250 <span class="comment">/*</span>
00251 <span class="comment">    while(1)</span>
00252 <span class="comment">    {</span>
00253 <span class="comment">        vt100SetCursorPos(18,0);</span>
00254 <span class="comment">        ax88796RegDump();</span>
00255 <span class="comment">    }</span>
00256 <span class="comment">*/</span>
00257 }
00258 
00259 
00260 <span class="keywordtype">void</span> ax88796BeginPacketSend(<span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> packetLength)
00261 {
00262     <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> sendPacketLength;
00263     sendPacketLength = (packetLength&gt;=ETHERNET_MIN_PACKET_LENGTH)?
00264                         (packetLength):(ETHERNET_MIN_PACKET_LENGTH);
00265     
00266     <span class="comment">//start the NIC</span>
00267     ax88796Write(CR,(RD2|START));
00268     
00269     <span class="comment">// still transmitting a packet - wait for it to finish</span>
00270     <span class="keywordflow">while</span>( ax88796Read(CR) &amp; TXP );
00271 
00272     <span class="comment">//load beginning page for transmit buffer</span>
00273     ax88796Write(TPSR,TXSTART_INIT);
00274     
00275     <span class="comment">//set start address for remote DMA operation</span>
00276     ax88796Write(RSAR0,0x00);
00277     ax88796Write(RSAR1,0x40);
00278     
00279     <span class="comment">//clear the packet stored interrupt</span>
00280     ax88796Write(ISR, PTX);
00281 
00282     <span class="comment">//load data byte count for remote DMA</span>
00283     ax88796Write(RBCR0, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)(packetLength));
00284     ax88796Write(RBCR1, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)(packetLength&gt;&gt;8));
00285 
00286     ax88796Write(TBCR0, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)(sendPacketLength));
00287     ax88796Write(TBCR1, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)((sendPacketLength)&gt;&gt;8));
00288     
00289     <span class="comment">//do remote write operation</span>
00290     ax88796Write(CR,0x12);
00291 }
00292 
00293 
00294 <span class="keywordtype">void</span> ax88796SendPacketData(<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> * localBuffer, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length)
00295 {
00296     <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i;
00297     
00298     <span class="keywordflow">for</span>(i=0;i&lt;length;i++)
00299         ax88796Write(RDMAPORT, localBuffer[i]);
00300 }
00301 
00302 
00303 <span class="keywordtype">void</span> ax88796EndPacketSend(<span class="keywordtype">void</span>)
00304 {
00305     <span class="comment">//send the contents of the transmit buffer onto the network</span>
00306     ax88796Write(CR,(RD2|TXP));
00307     
00308     <span class="comment">// clear the remote DMA interrupt</span>
00309     ax88796Write(ISR, RDC);
00310 }
00311 
00312 
00313 <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> ax88796BeginPacketRetreive(<span class="keywordtype">void</span>)
00314 {
00315     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> writePagePtr;
00316     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> readPagePtr;
00317     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> bnryPagePtr;
00318     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> i;
00319     
00320     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> pageheader[4];
00321     <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> rxlen;
00322     
00323     <span class="comment">// check for and handle an overflow</span>
00324     ax88796ProcessInterrupt();
00325     
00326     <span class="comment">// read CURR from page 1</span>
00327     ax88796Write(CR,(PS0|RD2|START));
00328     writePagePtr = ax88796Read(CURR);
00329     <span class="comment">// read the boundary register from page 0</span>
00330     ax88796Write(CR,(RD2|START));
00331     bnryPagePtr = ax88796Read(BNRY);
00332 
00333     <span class="comment">// first packet is at page bnryPtr+1</span>
00334     readPagePtr = bnryPagePtr+1;
00335     <span class="keywordflow">if</span>(readPagePtr &gt;= RXSTOP_INIT) readPagePtr = RXSTART_INIT;
00336     
00337     <span class="comment">// return if there is no packet in the buffer</span>
00338     <span class="keywordflow">if</span>( readPagePtr == writePagePtr )
00339     {
00340         <span class="keywordflow">return</span> 0;
00341     }
00342     
00343     <span class="comment">// clear the packet received interrupt flag</span>
00344     ax88796Write(ISR, PRX);
00345     
00346     <span class="comment">// if the boundary pointer is invalid,</span>
00347     <span class="comment">// reset the contents of the buffer and exit</span>
00348     <span class="keywordflow">if</span>( (bnryPagePtr &lt; RXSTART_INIT) || (bnryPagePtr &gt;= RXSTOP_INIT) )
00349     {
00350         ax88796Write(BNRY, RXSTART_INIT);
00351         ax88796Write(CR, (PS0|RD2|START));
00352         ax88796Write(CURR, RXSTART_INIT+1);
00353         ax88796Write(CR, (RD2|START));
00354         
00355 <span class="comment">//      rprintf("B");</span>
00356         <span class="keywordflow">return</span> 0;
00357     }
00358 
00359     <span class="comment">// initiate DMA to transfer the RTL8019 packet header</span>
00360     ax88796Write(RBCR0, 4);
00361     ax88796Write(RBCR1, 0);
00362     ax88796Write(RSAR0, 0);
00363     ax88796Write(RSAR1, readPagePtr);
00364     ax88796Write(CR, (RD0|START));
00365     <span class="keywordflow">for</span>(i=0;i&lt;4;i++)
00366         pageheader[i] = ax88796Read(RDMAPORT);
00367 
00368     <span class="comment">// end the DMA operation</span>
00369     ax88796Write(CR, (RD2|START));
00370     <span class="keywordflow">for</span>(i = 0; i &lt;= 20; i++)
00371         <span class="keywordflow">if</span>(ax88796Read(ISR) &amp; RDC)
00372             <span class="keywordflow">break</span>;
00373     ax88796Write(ISR, RDC);
00374     
00375     rxlen = (pageheader[PKTHEADER_PKTLENH]&lt;&lt;8) + pageheader[PKTHEADER_PKTLENL];
00376     NextPage = pageheader[PKTHEADER_NEXTPAGE];
00377     
00378     CurrentRetreiveAddress = (readPagePtr&lt;&lt;8) + 4;
00379     
00380     <span class="comment">// if the NextPage pointer is invalid, the packet is not ready yet - exit</span>
00381     <span class="keywordflow">if</span>( (NextPage &gt;= RXSTOP_INIT) || (NextPage &lt; RXSTART_INIT) )
00382     {
00383 <span class="comment">//      rprintf("N");</span>
00384 <span class="comment">//      rprintfu08(nextPage);</span>
00385         <span class="keywordflow">return</span> 0;
00386     }
00387 
00388     <span class="keywordflow">return</span> rxlen-4;
00389 }
00390 
00391 
00392 <span class="keywordtype">void</span> ax88796RetreivePacketData(<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> * localBuffer, <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> length)
00393 {
00394     <span class="keywordtype">unsigned</span> <span class="keywordtype">int</span> i;
00395     
00396     <span class="comment">// initiate DMA to transfer the data</span>
00397     ax88796Write(RBCR0, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)length);
00398     ax88796Write(RBCR1, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)(length&gt;&gt;8));
00399     ax88796Write(RSAR0, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)CurrentRetreiveAddress);
00400     ax88796Write(RSAR1, (<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span>)(CurrentRetreiveAddress&gt;&gt;8));
00401     ax88796Write(CR, (RD0|START));
00402     <span class="keywordflow">for</span>(i=0;i&lt;length;i++)
00403         localBuffer[i] = ax88796Read(RDMAPORT);
00404 
00405     <span class="comment">// end the DMA operation</span>
00406     ax88796Write(CR, (RD2|START));
00407     <span class="keywordflow">for</span>(i = 0; i &lt;= 20; i++)
00408         <span class="keywordflow">if</span>(ax88796Read(ISR) &amp; RDC)
00409             <span class="keywordflow">break</span>;
00410     ax88796Write(ISR, RDC);
00411     
00412     CurrentRetreiveAddress += length;
00413     <span class="keywordflow">if</span>( CurrentRetreiveAddress &gt;= 0x6000 )
00414         CurrentRetreiveAddress -= (0x6000-0x4600) ;
00415 }
00416 
00417 
00418 <span class="keywordtype">void</span> ax88796EndPacketRetreive(<span class="keywordtype">void</span>)
00419 {
00420     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> i;
00421     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> bnryPagePtr;
00422 
00423     <span class="comment">// end the DMA operation</span>
00424     ax88796Write(CR, (RD2|START));
00425     <span class="keywordflow">for</span>(i = 0; i &lt;= 20; i++)
00426         <span class="keywordflow">if</span>(ax88796Read(ISR) &amp; RDC)
00427             <span class="keywordflow">break</span>;
00428     ax88796Write(ISR, RDC);
00429 
00430     <span class="comment">// set the boundary register to point</span>
00431     <span class="comment">// to the start of the next packet-1</span>
00432     bnryPagePtr = NextPage-1;
00433     <span class="keywordflow">if</span>(bnryPagePtr &lt; RXSTART_INIT) bnryPagePtr = RXSTOP_INIT-1;
00434 
00435     ax88796Write(BNRY, bnryPagePtr);
00436 }
00437 
00438 
00439 <span class="keywordtype">void</span> ax88796ProcessInterrupt(<span class="keywordtype">void</span>)
00440 {
00441     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> intr = ax88796Read(ISR);
00442     
00443     <span class="comment">// check for receive overflow</span>
00444     <span class="keywordflow">if</span>( intr &amp; OVW )
00445         ax88796ReceiveOverflowRecover();
00446 }
00447 
00448 
00449 <span class="keywordtype">void</span> ax88796ReceiveOverflowRecover(<span class="keywordtype">void</span>)
00450 {
00451     <span class="comment">// receive buffer overflow handling procedure</span>
00452     <span class="comment">// as specified in the AX88796 datasheet</span>
00453 
00454     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> cmdReg;
00455     <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> resend=0;
00456 
00457     <span class="comment">// check if we were transmitting something</span>
00458     cmdReg = ax88796Read(CR);
00459     <span class="comment">// stop the interface</span>
00460     ax88796Write(CR, (RD2|STOP));
00461     <span class="comment">// wait for timeout</span>
00462     delay_ms(2);
00463     <span class="comment">// clear remote byte count registers</span>
00464     ax88796Write(RBCR0, 0x00);
00465     ax88796Write(RBCR1, 0x00);
00466     
00467     <span class="comment">// if we were transmitting something</span>