?lang_form? ?lang_select? ?lang_submit? ?lang_endform?

library

?curdirlinks? - Rev 6

?prevdifflink?

<!DOCTYPE <h <t <link </head><body> <!-- <div <h 00002 00003 00004 00005 00006 00007 00008 00009 00010 00011 00012 00013 00014 00015 00016 00017 00018 00019 00020 00021 00022 00023 00024 00025 00026 00027 00028 00029 00030 00031 00032 00033 00034 00035 00036 00037 00038 00039 00040 00041 00042 00043 00044 00045 00046 00047 00048 <a 00050 { 00051 00052 00053 00054 00055 00056 00057 00058 00059 00060 00061 00062 00063 00064 00065 00066 00067 00068 00069 00070 00071 00072 00073 00074 00075 00076 00077 00078 00079 00080 00081 00082 00083 00084 00085 sbi(GICR, INT2); 00086 00087 00088 sei(); 00089 } 00090 00091 <a 00093 { 00094 00095 00096 } 00097 00098 <a 00100 { 00101 00102 00103 00104 cbi(GICR, INT2); 00105 00106 00107 00108 } 00109 <a 00111 { 00112 u16 div; 00113 00114 00115 00116 { 00117 00118 00119 00120 00121 div = 64; 00122 } 00123 00124 { 00125 00126 00127 00128 00129 div = 256; 00130 } 00131 00132 00133 00134 00135 00136 } 00137 00138 <a 00140 { 00141 00142 00143 } 00144 <a 00146 { 00147 00148 00149 00150 00151 00152 00153 00154 00155 00156 00157 00158 00159 00160 00161 00162 00163 00164 00165 00166 } 00167 00168 <a 00170 { 00171 00172 00173 { 00174 00175 00176 { 00177 00178 00179 00180 } 00181 00182 { 00183 00184 00185 } 00186 } 00187 00188 { 00189 00190 00191 } 00192 } 00193 <a 00195 { 00196 00197 { 00198 00199 00200 { 00201 00202 00203 00204 00205 00206 00207 00208 00209 00210 00211 00212 } 00213 00214 { 00215 00216 00217 00218 00219 00220 00221 00222 00223 00224 00225 00226 } 00227 00228 { 00229 00230 00231 00232 00233 00234 } 00235 } 00236 <a 00238 { 00239 00240 00241 00242 00243 { 00244 00245 00246 00247 00248 00249 00250 00251 00252 00253 00254 00255 00256 00257 00258 00259 00260 00261 } 00262 00263 { 00264 00265 00266 00267 00268 00269 00270 00271 00272 00273 00274 00275 00276 00277 00278 00279 00280 } 00281 00282 00283 00284 00285 00286 00287 00288 00289 { 00290 00291 00292 00293 00294 00295 00296 00297 00298 00299 00300 } 00301 } 00302 } 00303 00304 00305 { 00306 00307 00308 } </ <a <img </body> </html>

HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> tml><head><meta http-equiv="Content-Type" content="text/html;charset=iso-8859-1"> itle>Procyon AVRlib: uartsw2.c Source File</title> href="dox.css" rel="stylesheet" type="text/css"> Generated by Doxygen 1.4.2 --> class="qindex"><a class="qindex" href="main.html">Main Page</a> | <a class="qindex" href="modules.html">Modules</a> | <a class="qindex" href="annotated.html">Data Structures</a> | <a class="qindex" href="dirs.html">Directories</a> | <a class="qindex" href="files.html">File List</a> | <a class="qindex" href="functions.html">Data Fields</a> | <a class="qindex" href="globals.html">Globals</a> | <a class="qindex" href="pages.html">Related Pages</a></div> 1>uartsw2.c</h1><a href="uartsw2_8c.html">Go to the documentation of this file.</a><div class="fragment"><pre class="fragment">00001 /*! \file uartsw2.c \brief Software Interrupt-driven UART Driver. */ //***************************************************************************** // // File Name : 'uartsw2.c' // Title : Software Interrupt-driven UART Driver // Author : Pascal Stang - Copyright (C) 2002-2004 // Created : 7/20/2002 // Revised : 4/27/2004 // Version : 0.6 // Target MCU : Atmel AVR Series (intended for the ATmega16 and ATmega32) // Editor Tabs : 4 // // This code is distributed under the GNU Public License // which can be found at http://www.gnu.org/licenses/gpl.txt // //***************************************************************************** #include <avr/io.h> #include <avr/interrupt.h> #include "<a class="code" href="global_8h.html">global.h</a>" #include "<a class="code" href="timer_8h.html">timer.h</a>" #include "<a class="code" href="uartsw2_8h.html">uartsw2.h</a>" // Program ROM constants // Global variables // uartsw transmit status and data variables static volatile u08 UartswTxBusy; static volatile u08 UartswTxData; static volatile u08 UartswTxBitNum; // baud rate common to transmit and receive static volatile u08 UartswBaudRateDiv; // uartsw receive status and data variables static volatile u08 UartswRxBusy; static volatile u08 UartswRxData; static volatile u08 UartswRxBitNum; // receive buffer static <a class="code" href="structstruct__cBuffer.html">cBuffer</a> uartswRxBuffer; ///< uartsw receive buffer // automatically allocate space in ram for each buffer static char uartswRxData[<a class="code" href="uartsw2conf_8h.html#a0">UARTSW_RX_BUFFER_SIZE</a>]; // functions //! enable and initialize the software uart name="l00049"></a><a class="code" href="uartsw2_8c.html#a9">00049</a> void <a class="code" href="uartsw_8c.html#a9">uartswInit</a>(void) // initialize the buffers <a class="code" href="uartsw_8c.html#a10">uartswInitBuffers</a>(); // initialize the ports sbi(<a class="code" href="uartsw2conf_8h.html#a3">UARTSW_TX_DDR</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #ifdef UARTSW_INVERT cbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #else sbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #endif cbi(<a class="code" href="uartsw2conf_8h.html#a6">UARTSW_RX_DDR</a>, <a class="code" href="uartsw2conf_8h.html#a8">UARTSW_RX_PIN</a>); cbi(<a class="code" href="uartsw2conf_8h.html#a5">UARTSW_RX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a8">UARTSW_RX_PIN</a>); // initialize baud rate <a class="code" href="uartsw_8c.html#a12">uartswSetBaudRate</a>(9600); // setup the transmitter UartswTxBusy = FALSE; // disable OC2 interrupt cbi(TIMSK, OCIE2); // attach TxBit service routine to OC2 <a class="code" href="group__timer.html#ga8">timerAttach</a>(TIMER2OUTCOMPARE_INT, <a class="code" href="uartsw_8c.html#a16">uartswTxBitService</a>); // setup the receiver UartswRxBusy = FALSE; // disable OC0 interrupt cbi(TIMSK, OCIE0); // attach RxBit service routine to OC0 <a class="code" href="group__timer.html#ga8">timerAttach</a>(TIMER0OUTCOMPARE_INT, <a class="code" href="uartsw_8c.html#a17">uartswRxBitService</a>); // INT2 trigger on rising/falling edge #ifdef UARTSW_INVERT sbi(MCUCSR, ISC2); // rising edge #else cbi(MCUCSR, ISC2); // falling edge #endif // enable INT2 interrupt // turn on interrupts //! create and initialize the uart buffers name="l00092"></a><a class="code" href="uartsw2_8c.html#a10">00092</a> void <a class="code" href="uartsw_8c.html#a10">uartswInitBuffers</a>(void) // initialize the UART receive buffer <a class="code" href="group__buffer.html#ga1">bufferInit</a>(&uartswRxBuffer, uartswRxData, <a class="code" href="uartsw2conf_8h.html#a0">UARTSW_RX_BUFFER_SIZE</a>); //! turns off software UART name="l00099"></a><a class="code" href="uartsw2_8c.html#a11">00099</a> void <a class="code" href="uartsw_8c.html#a11">uartswOff</a>(void) // disable interrupts cbi(TIMSK, OCIE2); cbi(TIMSK, OCIE0); // detach the service routines <a class="code" href="group__timer.html#ga9">timerDetach</a>(TIMER2OUTCOMPARE_INT); <a class="code" href="group__timer.html#ga9">timerDetach</a>(TIMER0OUTCOMPARE_INT); name="l00110"></a><a class="code" href="uartsw2_8c.html#a12">00110</a> void <a class="code" href="uartsw_8c.html#a12">uartswSetBaudRate</a>(u32 baudrate) // set timer prescaler if( baudrate > (F_CPU/64L*256L) ) // if the requested baud rate is high, // set timer prescalers to div-by-64 <a class="code" href="group__timer128.html#ga8">timer2SetPrescaler</a>(<a class="code" href="group__timer.html#ga28">TIMERRTC_CLK_DIV64</a>); <a class="code" href="group__timer.html#ga4">timer0SetPrescaler</a>(<a class="code" href="group__timer.html#ga18">TIMER_CLK_DIV64</a>); else // if the requested baud rate is low, // set timer prescalers to div-by-256 <a class="code" href="group__timer128.html#ga8">timer2SetPrescaler</a>(<a class="code" href="group__timer.html#ga30">TIMERRTC_CLK_DIV256</a>); <a class="code" href="group__timer.html#ga4">timer0SetPrescaler</a>(<a class="code" href="group__timer.html#ga19">TIMER_CLK_DIV256</a>); // calculate division factor for requested baud rate, and set it //UartswBaudRateDiv = (u08)(((F_CPU/64L)+(baudrate/2L))/(baudrate*1L)); //UartswBaudRateDiv = (u08)(((F_CPU/256L)+(baudrate/2L))/(baudrate*1L)); UartswBaudRateDiv = (u08)(((F_CPU/div)+(baudrate/2L))/(baudrate*1L)); //! returns the receive buffer structure name="l00139"></a><a class="code" href="uartsw2_8c.html#a13">00139</a> <a class="code" href="structstruct__cBuffer.html">cBuffer</a>* <a class="code" href="uartsw_8c.html#a13">uartswGetRxBuffer</a>(void) // return rx buffer pointer return &uartswRxBuffer; name="l00145"></a><a class="code" href="uartsw2_8c.html#a14">00145</a> void <a class="code" href="uartsw_8c.html#a14">uartswSendByte</a>(u08 data) // wait until uart is ready while(UartswTxBusy); // set busy flag UartswTxBusy = TRUE; // save data UartswTxData = data; // set number of bits (+1 for stop bit) UartswTxBitNum = 9; // set the start bit #ifdef UARTSW_INVERT sbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #else cbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #endif // schedule the next bit outb(OCR2, inb(TCNT2) + UartswBaudRateDiv); // enable OC2 interrupt sbi(TIMSK, OCIE2); //! gets a byte (if available) from the uart receive buffer name="l00169"></a><a class="code" href="uartsw2_8c.html#a15">00169</a> u08 <a class="code" href="uartsw_8c.html#a15">uartswReceiveByte</a>(u08* rxData) // make sure we have a receive buffer if(uartswRxBuffer.<a class="code" href="structstruct__cBuffer.html#o1">size</a>) // make sure we have data if(uartswRxBuffer.<a class="code" href="structstruct__cBuffer.html#o2">datalength</a>) // get byte from beginning of buffer *rxData = <a class="code" href="group__buffer.html#ga2">bufferGetFromFront</a>(&uartswRxBuffer); return TRUE; else // no data return FALSE; else // no buffer return FALSE; name="l00194"></a><a class="code" href="uartsw2_8c.html#a16">00194</a> void <a class="code" href="uartsw_8c.html#a16">uartswTxBitService</a>(void) if(UartswTxBitNum) // there are bits still waiting to be transmitted if(UartswTxBitNum > 1) // transmit data bits (inverted, LSB first) #ifdef UARTSW_INVERT if( !(UartswTxData & 0x01) ) #else if( (UartswTxData & 0x01) ) #endif sbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); else cbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); // shift bits down UartswTxData = UartswTxData>>1; else // transmit stop bit #ifdef UARTSW_INVERT cbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #else sbi(<a class="code" href="uartsw2conf_8h.html#a2">UARTSW_TX_PORT</a>, <a class="code" href="uartsw2conf_8h.html#a4">UARTSW_TX_PIN</a>); #endif } // schedule the next bit outb(OCR2, inb(OCR2) + UartswBaudRateDiv); // count down UartswTxBitNum--; else // transmission is done // clear busy flag UartswTxBusy = FALSE; // disable OC2 interrupt cbi(TIMSK, OCIE2); name="l00237"></a><a class="code" href="uartsw2_8c.html#a17">00237</a> void <a class="code" href="uartsw_8c.html#a17">uartswRxBitService</a>(void) // this function runs on either: // - a rising edge interrupt // - Timer 0 output compare if(!UartswRxBusy) // UART was not previously busy, // this must be is a start bit // disable INT2 interrupt cbi(GICR, INT2); // schedule data bit sampling 1.5 bit periods from now outb(OCR0, inb(TCNT0) + UartswBaudRateDiv + UartswBaudRateDiv/2); // clear OC0 interrupt flag sbi(TIFR, OCF0); // enable OC0 interrupt sbi(TIMSK, OCIE0); // set busy flag UartswRxBusy = TRUE; // reset bit counter UartswRxBitNum = 0; // reset data UartswRxData = 0; else // start bit has already been received // we're in the data bits // shift data byte to make room for new bit UartswRxData = UartswRxData>>1; // sample the data line #ifdef UARTSW_INVERT if( !(inb(<a class="code" href="uartsw2conf_8h.html#a7">UARTSW_RX_PORTIN</a>) & (1<<<a class="code" href="uartsw2conf_8h.html#a8">UARTSW_RX_PIN</a>)) ) #else if( (inb(<a class="code" href="uartsw2conf_8h.html#a7">UARTSW_RX_PORTIN</a>) & (1<<<a class="code" href="uartsw2conf_8h.html#a8">UARTSW_RX_PIN</a>)) ) #endif { // serial line is marking // record '1' bit UartswRxData |= 0x80; // increment bit counter UartswRxBitNum++; // schedule next bit sample outb(OCR0, inb(OCR0) + UartswBaudRateDiv); // check if we have a full byte if(UartswRxBitNum >= 8) // save data in receive buffer <a class="code" href="group__buffer.html#ga5">bufferAddToEnd</a>(&uartswRxBuffer, UartswRxData); // disable OC0 interrupt cbi(TIMSK, OCIE0); // clear INT2 interrupt flag sbi(GIFR, INTF2); // enable INT interrupt sbi(GICR, INT2); // clear busy flag UartswRxBusy = FALSE; <a class="code" href="a2d_8c.html#a10">SIGNAL</a>(SIG_INTERRUPT2) // run RxBit service routine <a class="code" href="uartsw_8c.html#a17">uartswRxBitService</a>(); pre></div><hr size="1"><address style="align: right;">Generated on Sun Oct 29 03:41:08 2006 for Procyon AVRlib by  href="http://www.doxygen.org/index.html"> src="doxygen.png" alt="doxygen" align="middle" border="0"></a> 1.4.2 </address>

END}