//********************************************************************************************
//
// File : enc28j60.c Microchip ENC28J60 Ethernet Interface Driver
//
//********************************************************************************************
//
// Copyright (C) 2007
//
// This program is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free Software
// Foundation; either version 2 of the License, or (at your option) any later
// version.
// This program is distributed in the hope that it will be useful, but
//
// WITHOUT ANY WARRANTY;
//
// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
// PURPOSE. See the GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along with
// this program; if not, write to the Free Software Foundation, Inc., 51
// Franklin St, Fifth Floor, Boston, MA 02110, USA
//
// http://www.gnu.de/gpl-ger.html
//
//********************************************************************************************#include "includes.h"////#define F_CPU 8000000UL  // 8 MHz//struct enc28j60_flag
//{
//	unsigned rx_buffer_is_free:1;
//	unsigned unuse:7;
//}enc28j60_flag;static BYTE Enc28j60Bank;static WORD_BYTES next_packet_ptr;
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************BYTE enc28j60ReadOp(BYTE op, BYTE address){
	// activate CS	CSACTIVE;	// issue read command	SPDR = op | (address & ADDR_MASK);	waitspi();	// read data	SPDR = 0x00;	waitspi();	// do dummy read if needed (for mac and mii, see datasheet page 29)	if(address & 0x80)	{		SPDR = 0x00;		waitspi();	}	// release CS	CSPASSIVE;	return(SPDR);}//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************void enc28j60WriteOp(BYTE op, BYTE address, BYTE data){	CSACTIVE;	// issue write command	SPDR = op | (address & ADDR_MASK);	waitspi();	// write data	SPDR = data;	waitspi();	CSPASSIVE;}//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************void enc28j60SetBank(BYTE address){	// set the bank (if needed)	if((address & BANK_MASK) != Enc28j60Bank)	{		// set the bank		enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, ECON1, (ECON1_BSEL1|ECON1_BSEL0));		enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, (address & BANK_MASK)>>5);		Enc28j60Bank = (address & BANK_MASK);	}}//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************BYTE enc28j60Read(BYTE address){	// select bank to read	enc28j60SetBank(address);	
	// do the read	return enc28j60ReadOp(ENC28J60_READ_CTRL_REG, address);}//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************void enc28j60Write(BYTE address, BYTE data){	// select bank to write	enc28j60SetBank(address);
	// do the write	enc28j60WriteOp(ENC28J60_WRITE_CTRL_REG, address, data);}
//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
WORD enc28j60_read_phyreg(BYTE address)
{
	WORD data;
	
	// set the PHY register address	enc28j60Write(MIREGADR, address);
	enc28j60Write(MICMD, MICMD_MIIRD);
	
	// Loop to wait until the PHY register has been read through the MII
	// This requires 10.24us
	while( (enc28j60Read(MISTAT) & MISTAT_BUSY) );
	
	// Stop reading
	enc28j60Write(MICMD, MICMD_MIIRD);
	
	// Obtain results and return
	data = enc28j60Read ( MIRDL );
	data |= enc28j60Read ( MIRDH );

	return data;
}//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************void enc28j60PhyWrite(BYTE address, WORD_BYTES data){	// set the PHY register address	enc28j60Write(MIREGADR, address);	// write the PHY data	enc28j60Write(MIWRL, data.byte.low);	enc28j60Write(MIWRH, data.byte.high);	// wait until the PHY write completes	while(enc28j60Read(MISTAT) & MISTAT_BUSY)
	{		_delay_us(15);	}}//*******************************************************************************************
//
// Function : icmp_send_request
// Description : Send ARP request packet to destination.
//
//*******************************************************************************************
/*
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);

	// 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);

	//initialize enc28j60/
	//enc28j60Init( avr_mac );
	//_delay_ms( 20 );


	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 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);

	

	// 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
	enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, MACON3, MACON3_PADCFG0|MACON3_TXCRCEN|MACON3_FRMLNEN);
	// set inter-frame gap (non-back-to-back)
	enc28j60Write(MAIPGL, 0x12);
	enc28j60Write(MAIPGH, 0x0C);
	// set inter-frame gap (back-to-back)
	enc28j60Write(MABBIPG, 0x12);
	// 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});
	// 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);



	// Magjack leds configuration, see enc28j60 datasheet, page 11 /
	// LEDB=yellow LEDA=green
	//
	// 0x476 is PHLCON LEDA=links status, LEDB=receive/transmit