/*********************************************
* vim:sw=8:ts=8:si:et
* To use the above modeline in vim you must have "set modeline" in your .vimrc
* Author: Guido Socher
* Copyright: GPL V2
* http://www.gnu.org/licenses/gpl.html
*
* Based on the enc28j60.c file from the AVRlib library by Pascal Stang.
* For AVRlib See http://www.procyonengineering.com/
* Used with explicit permission of Pascal Stang.
*
* Title: Microchip ENC28J60 Ethernet Interface Driver
* Chip type : ATMEGA88 with ENC28J60
*********************************************/
#include <avr/io.h>
#include "avr_compat.h"
#include "enc28j60.h"
#include "enc28j60_cfg.h"
#include "timeout.h"
//
#ifndef ALIBC_OLD
#include <util/delay.h>
#else
#include <avr/delay.h>
#endif
static uint8_t Enc28j60Bank;
static uint16_t NextPacketPtr;
// set CS to 0 = active
#define CSACTIVE ENC28J60_CONTROL_PORT&=~(1<<ENC28J60_CONTROL_CS)
// set CS to 1 = passive
#define CSPASSIVE ENC28J60_CONTROL_PORT|=(1<<ENC28J60_CONTROL_CS)
//
#define waitspi() while(!(SPSR&(1<<SPIF)))
uint8_t enc28j60ReadOp(uint8_t op, uint8_t address)
{
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);
}
void enc28j60WriteOp(uint8_t op, uint8_t address, uint8_t data)
{
CSACTIVE;
// issue write command
SPDR = op | (address & ADDR_MASK);
waitspi();
// write data
SPDR = data;
waitspi();
CSPASSIVE;
}
void enc28j60ReadBuffer(uint16_t len, uint8_t* data)
{
CSACTIVE;
// issue read command
SPDR = ENC28J60_READ_BUF_MEM;
waitspi();
while(len)
{
len--;
// read data
SPDR = 0x00;
waitspi();
*data = SPDR;
data++;
}
*data='\0';
CSPASSIVE;
}
void enc28j60WriteBuffer(uint16_t len, uint8_t* data)
{
CSACTIVE;
// issue write command
SPDR = ENC28J60_WRITE_BUF_MEM;
waitspi();
while(len)
{
len--;
// write data
SPDR = *data;
data++;
waitspi();
}
CSPASSIVE;
}
void enc28j60SetBank(uint8_t 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);
}
}
uint8_t enc28j60Read(uint8_t address)
{
// set the bank
enc28j60SetBank(address);
// do the read
return enc28j60ReadOp(ENC28J60_READ_CTRL_REG, address);
}
void enc28j60Write(uint8_t address, uint8_t data)
{
// set the bank
enc28j60SetBank(address);
// do the write
enc28j60WriteOp(ENC28J60_WRITE_CTRL_REG, address, data);
}
void enc28j60PhyWrite(uint8_t address, uint16_t data)
{
// set the PHY register address
enc28j60Write(MIREGADR, address);
// write the PHY data
enc28j60Write(MIWRL, data);
enc28j60Write(MIWRH, data>>8);
// wait until the PHY write completes
while(enc28j60Read(MISTAT) & MISTAT_BUSY){
_delay_us(15);
}
}
void enc28j60Init(uint8_t* macaddr)
{
// initialize I/O
ENC28J60_CONTROL_DDR |= 1<<ENC28J60_CONTROL_CS;
CSPASSIVE;
//
DDRB |= 1<<PB3 | 1<<PB5; // mosi, sck output
cbi(DDRB,PINB4); // MISO is input
//
CSPASSIVE;
cbi(PORTB,PB3); // MOSI low
cbi(PORTB,PB5); // SCK low
//
// initialize SPI interface
// master mode and Fosc/2 clock:
SPCR = (1<<SPE)|(1<<MSTR);
SPSR |= (1<<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
NextPacketPtr = 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
enc28j60Write(MAADR5, macaddr[0]);
enc28j60Write(MAADR4, macaddr[1]);
enc28j60Write(MAADR3, macaddr[2]);
enc28j60Write(MAADR2, macaddr[3]);
enc28j60Write(MAADR1, macaddr[4]);
enc28j60Write(MAADR0, macaddr[5]);
// no loopback of transmitted frames
enc28j60PhyWrite(PHCON2, 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);
}
// read the revision of the chip:
uint8_t enc28j60getrev(void)
{
return(enc28j60Read(EREVID));
}
void enc28j60PacketSend(uint16_t len, uint8_t* packet)
{
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_TXRST);
enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, ECON1, ECON1_TXRST);
// Set the write pointer to start of transmit buffer area
enc28j60Write(EWRPTL, TXSTART_INIT&0xFF);
enc28j60Write(EWRPTH, TXSTART_INIT>>8);
// Set the TXND pointer to correspond to the packet size given
enc28j60Write(ETXNDL, (TXSTART_INIT+len)&0xFF);
enc28j60Write(ETXNDH, (TXSTART_INIT+len)>>8);
// write per-packet control byte (0x00 means use macon3 settings)
enc28j60WriteOp(ENC28J60_WRITE_BUF_MEM, 0, 0x00);
// copy the packet into the transmit buffer
enc28j60WriteBuffer(len, packet);
// Reset the transmit logic problem. See Rev. B4 Silicon Errata point 12.
if( (enc28j60Read(EIR) & EIR_TXERIF) ){
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_TXRST);
enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, ECON1, ECON1_TXRST);
//enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, ECON1, ECON1_TXRTS);
enc28j60WriteOp(ENC28J60_BIT_FIELD_CLR, EIR, EIR_TXERIF);
}
// send the contents of the transmit buffer onto the network
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON1, ECON1_TXRTS);
}
// Gets a packet from the network receive buffer, if one is available.
// The packet will by headed by an ethernet header.
// maxlen The maximum acceptable length of a retrieved packet.
// packet Pointer where packet data should be stored.
// Returns: Packet length in bytes if a packet was retrieved, zero otherwise.
uint16_t enc28j60PacketReceive(uint16_t maxlen, uint8_t* packet)
{
uint16_t rxstat;
uint16_t len;
// check if a packet has been received and buffered
//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, (NextPacketPtr));
enc28j60Write(ERDPTH, (NextPacketPtr)>>8);
// read the next packet pointer
NextPacketPtr = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
NextPacketPtr |= enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0)<<8;
// read the packet length (see datasheet page 43)
len = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
len |= enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0)<<8;
len-=4; //remove the CRC count
// read the receive status (see datasheet page 43)
rxstat = enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0);
rxstat |= enc28j60ReadOp(ENC28J60_READ_BUF_MEM, 0)<<8;
// limit retrieve length
if (len>maxlen-1){
len=maxlen-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 ((rxstat & 0x80)==0){
// invalid
len=0;
}else{
// copy the packet from the receive buffer
enc28j60ReadBuffer(len, packet);
}
// Move the RX read pointer to the start of the next received packet
// This frees the memory we just read out
enc28j60Write(ERXRDPTL, (NextPacketPtr));
enc28j60Write(ERXRDPTH, (NextPacketPtr)>>8);
// decrement the packet counter indicate we are done with this packet
enc28j60WriteOp(ENC28J60_BIT_FIELD_SET, ECON2, ECON2_PKTDEC);
return(len);
}