enc28j60.c

此为ATMEGA32+ENC28J60以太网通信很好的代码,含液晶 按键 HTTP WENB页面显示 已经调试通过.

	//enc28j60PhyWrite( PHLCON, 0x0476 );

	//enc28j60_flag.rx_buffer_is_free = 1;
	_delay_ms(20);
}
*/
void enc28j60_init( BYTE *avr_mac)
{
	// initialize I/O
	//DDRB |= _BV( DDB4 );
	//CSPASSIVE;

	// enable PB0, reset as output 
	ENC28J60_DDR |= _BV(ENC28J60_RESET_PIN_DDR);

	// enable PD2/INT0, as input
	ENC28J60_DDR &= ~_BV(ENC28J60_INT_PIN_DDR);
	ENC28J60_PORT |= _BV(ENC28J60_INT_PIN);

	// set output to gnd, reset the ethernet chip
	ENC28J60_PORT &= ~_BV(ENC28J60_RESET_PIN);
	_delay_ms(10);

	// set output to Vcc, reset inactive
	ENC28J60_PORT |= _BV(ENC28J60_RESET_PIN);
	_delay_ms(200);

    //	
	DDRB  |= _BV( DDB4 ) | _BV( DDB5 ) | _BV( DDB7 ); // mosi, sck, ss output
	//DDRB &= ~_BV( DDB6 ); // MISO is input

	CSPASSIVE;
	PORTB &= ~(_BV( PB5 ) | _BV( PB7 ) );
	//
	// initialize SPI interface
	// master mode and Fosc/2 clock:
    SPCR = _BV( SPE ) | _BV( MSTR );
    SPSR |= _BV( SPI2X );

	// perform system reset
	enc28j60WriteOp(ENC28J60_SOFT_RESET, 0, ENC28J60_SOFT_RESET);
	_delay_ms(50);

	// check CLKRDY bit to see if reset is complete
	// The CLKRDY does not work. See Rev. B4 Silicon Errata point. Just wait.
	//while(!(enc28j60Read(ESTAT) & ESTAT_CLKRDY));
	// do bank 0 stuff
	// initialize receive buffer
	// 16-bit transfers, must write low byte first
	// set receive buffer start address
	next_packet_ptr.word = RXSTART_INIT;
    // Rx start
	enc28j60Write(ERXSTL, RXSTART_INIT&0xFF);
	enc28j60Write(ERXSTH, RXSTART_INIT>>8);
	// set receive pointer address
	enc28j60Write(ERXRDPTL, RXSTART_INIT&0xFF);
	enc28j60Write(ERXRDPTH, RXSTART_INIT>>8);
	// RX end
	enc28j60Write(ERXNDL, RXSTOP_INIT&0xFF);
	enc28j60Write(ERXNDH, RXSTOP_INIT>>8);
	// TX start
	enc28j60Write(ETXSTL, TXSTART_INIT&0xFF);
	enc28j60Write(ETXSTH, TXSTART_INIT>>8);
	// TX end
	enc28j60Write(ETXNDL, TXSTOP_INIT&0xFF);
	enc28j60Write(ETXNDH, TXSTOP_INIT>>8);

	// do bank 2 stuff
	// enable MAC receive
	enc28j60Write(MACON1, MACON1_MARXEN|MACON1_TXPAUS|MACON1_RXPAUS);
	
	// bring MAC out of reset
	//enc28j60Write(MACON2, 0x00);

	// enable automatic padding to 60bytes and CRC operations
	enc28j60Write(MACON3, MACON3_PADCFG0|MACON3_TXCRCEN|MACON3_FRMLNEN);

	// Allow infinite deferals if the medium is continuously busy 
    // (do not time out a transmission if the half duplex medium is 
    // completely saturated with other people's data)
    enc28j60Write(MACON4, MACON4_DEFER);

	// Late collisions occur beyond 63+8 bytes (8 bytes for preamble/start of frame delimiter)
	// 55 is all that is needed for IEEE 802.3, but ENC28J60 B5 errata for improper link pulse 
	// collisions will occur less often with a larger number.
    enc28j60Write(MACLCON2, 63);
	
	// Set non-back-to-back inter-packet gap to 9.6us.  The back-to-back 
	// inter-packet gap (MABBIPG) is set by MACSetDuplex() which is called 
	// later.
	enc28j60Write(MAIPGL, 0x12);
	enc28j60Write(MAIPGH, 0x0C);
	
	// Set the maximum packet size which the controller will accept
    // Do not send packets longer than MAX_FRAMELEN:
	enc28j60Write(MAMXFLL, MAX_FRAMELEN&0xFF);	
	enc28j60Write(MAMXFLH, MAX_FRAMELEN>>8);
	
	// do bank 3 stuff
    // write MAC address
	// NOTE: MAC address in ENC28J60 is byte-backward
	// ENC28J60 is big-endian avr gcc is little-endian
	enc28j60Write(MAADR5, avr_mac[0]);
	enc28j60Write(MAADR4, avr_mac[1]);
	enc28j60Write(MAADR3, avr_mac[2]);
	enc28j60Write(MAADR2, avr_mac[3]);
	enc28j60Write(MAADR1, avr_mac[4]);
	enc28j60Write(MAADR0, avr_mac[5]);
	
	// no loopback of transmitted frames
	enc28j60PhyWrite(PHCON2, (WORD_BYTES){PHCON2_HDLDIS});
	
	// Magjack leds configuration, see enc28j60 datasheet, page 11
	// 0x476 is PHLCON LEDA=links status, LEDB=receive/transmit
	// enc28j60PhyWrite(PHLCON,0b0000 0100 0111 00 10);
	enc28j60PhyWrite(PHLCON,(WORD_BYTES){0x0472});

	// do bank 1 stuff, packet filter:
	// For broadcast packets we allow only ARP packtets
	// All other packets should be unicast only for our mac (MAADR)
	//
	// The pattern to match on is therefore
	// Type     ETH.DST
	// ARP      BROADCAST
 	// 06 08 -- ff ff ff ff ff ff -> ip checksum for theses bytes=f7f9
	// in binary these poitions are:11 0000 0011 1111
	// This is hex 303F->EPMM0=0x3f,EPMM1=0x30
	enc28j60Write(ERXFCON, ERXFCON_UCEN|ERXFCON_CRCEN|ERXFCON_PMEN);
	enc28j60Write(EPMM0, 0x3f);
	enc28j60Write(EPMM1, 0x30);
	enc28j60Write(EPMCSL, 0xf9);
	enc28j60Write(EPMCSH, 0xf7);

	// set inter-frame gap (back-to-back)
	enc28j60Write(MABBIPG, 0x12);
	
	// switch to bank 0
	enc28j60SetBank(ECON1);

	// enable interrutps
	enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, EIE, EIE_INTIE|EIE_PKTIE);

	// enable packet reception
	enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_RXEN);

	_delay_ms(20);
}
//*******************************************************************************************
//
// Function : enc28j60getrev
// Description : read the revision of the chip.
//
//*******************************************************************************************
BYTE enc28j60getrev(void)
{
	return(enc28j60Read(EREVID));
}
//*******************************************************************************************
//
// Function : enc28j60_packet_send
// Description : Send packet to network.
//
//*******************************************************************************************
void enc28j60_packet_send ( BYTE *buffer, WORD length )
{
	//Set the write pointer to start of transmit buffer area
	enc28j60Write(EWRPTL, LOW(TXSTART_INIT) );            //EWRPTL写指针
	enc28j60Write(EWRPTH, HIGH(TXSTART_INIT) );

	// Set the TXND pointer to correspond to the packet size given
	enc28j60Write(ETXNDL, LOW((TXSTART_INIT+length)) );    //发送结束低字节（ETXND<7:0>）
	enc28j60Write(ETXNDH, HIGH((TXSTART_INIT+length)) );

	// write per-packet control byte (0x00 means use macon3 settings)
	enc28j60WriteOp(ENC28J60_WRITE_BUF_MEM, 0, 0x00);

	CSACTIVE;
	// issue write command
	SPDR = ENC28J60_WRITE_BUF_MEM;
	waitspi();
	while(length)
	{
		length--;
		// write data
		SPDR = *buffer++;
		waitspi();
	}
	CSPASSIVE;
	
	// send the contents of the transmit buffer onto the network
	enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_TXRTS);       //将ECON1.TXRTS 位置1 开始发送。
	                                                                   //TXRTS：发送请求位
                                                                     //1 = 发送逻辑正在尝试发送数据包
                                                                     //0 = 发送逻辑空闲

	// Reset the transmit logic problem. See Rev. B4 Silicon Errata point 12.
	if( (enc28j60Read(EIR) & EIR_TXERIF) )                              //TXERIF： 发送错误中断标志位
                                                                      //1 = 已发生发送错误中断
                                                                      //0 = 未发生发送错误中断
	{
		enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, ECON1, ECON1_TXRTS);
	}
}
//*******************************************************************************************
//
// Function : enc28j60_mac_is_linked
// Description : return MAC link status.
//
//*******************************************************************************************
/*
BYTE enc28j60_mac_is_linked(void)
{
	if ( (enc28j60_read_phyreg(PHSTAT1) & PHSTAT1_LLSTAT ) )
		return 1;
	else
		return 0;
}
*/
//*******************************************************************************************
//
// Function : enc28j60_packet_receive
// Description : check received packet and return length of data
//
//*******************************************************************************************
//WORD data_length;
WORD enc28j60_packet_receive ( BYTE *rxtx_buffer, WORD max_length )
{
	WORD_BYTES rx_status, data_length;
	
	// check if a packet has been received and bufferedPKTIF： 接收数据包待处理中断标志位
//1 = 接收缓冲器包含一个或多个未处理的数据包；当PKTDEC 置1 时清零
//0 = 接收缓冲器为空
	// if( !(enc28j60Read(EIR) & EIR_PKTIF) ){     //
	// The above does not work. See Rev. B4 Silicon Errata point 6.
	if( enc28j60Read(EPKTCNT) == 0 )
	{
		return 0;
	}

	// Set the read pointer to the start of the received packet
	enc28j60Write(ERDPTL, next_packet_ptr.bytes[0]);
	enc28j60Write(ERDPTH, next_packet_ptr.bytes[1]);

	// read the next packet pointer
	next_packet_ptr.bytes[0] = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
	next_packet_ptr.bytes[1] = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);

	// read the packet length (see datasheet page 43)
	data_length.bytes[0] = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
	data_length.bytes[1] = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
	data_length.word -=4; //remove the CRC count
	
	// read the receive status (see datasheet page 43)
	rx_status.bytes[0] = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
	rx_status.bytes[1] = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
	
	if ( data_length.word > (max_length-1) )
	{
		data_length.word = max_length-1;
	}
	
	// check CRC and symbol errors (see datasheet page 44, table 7-3):
	// The ERXFCON.CRCEN is set by default. Normally we should not
	// need to check this.
	if ( (rx_status.word & 0x80)==0 )
	{
		// invalid
		data_length.word = 0;
	}
	else
	{
		// read data from rx buffer and save to rxtx_buffer
		rx_status.word = data_length.word;
		CSACTIVE;
		// issue read command
		SPDR = ENC28J60_READ_BUF_MEM;
		waitspi();
		while(rx_status.word)
		{
			rx_status.word--;
			SPDR = 0x00;
			waitspi();
			*rxtx_buffer++ = SPDR;
		}
		CSPASSIVE;
	}
	
	// Move the RX read pointer to the start of the next received packet
	// This frees the memory we just read out
	enc28j60Write(ERXRDPTL, next_packet_ptr.bytes[0]);
	enc28j60Write(ERXRDPTH, next_packet_ptr.bytes[1]);

	// decrement the packet counter indicate we are done with this packet
	enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON2, ECON2_PKTDEC);

	return( data_length.word );
}