EtherCard
Ardino interface library for the ENC28J60 Ethernet controller chip (GPL).
persistence.ino
// Demo for using persistence flag and readPacketSlice()
//
// License: GPLv2
#include <EtherCard.h>
// ethernet interface mac address, must be unique on the LAN
static byte mymac[] = { 0x74,0x69,0x69,0x2D,0x30,0x31 };
// the buffersize must be relatively large for DHCP to work; when
// using static setup a buffer size of 100 is sufficient;
#define BUFFERSIZE 350
byte Ethernet::buffer[BUFFERSIZE];
const char website[] PROGMEM = "textfiles.com";
uint32_t nextSeq;
// called when the client request is complete
static void my_callback (byte status, word off, word len) {
if (strncmp_P((char*) Ethernet::buffer+off,PSTR("HTTP"),4) == 0) {
Serial.println(">>>");
// first reply packet
nextSeq = ether.getSequenceNumber();
}
if (nextSeq != ether.getSequenceNumber()) { Serial.print(F("<IGNORE DUPLICATE(?) PACKET>")); return; }
uint16_t payloadlength = ether.getTcpPayloadLength();
int16_t chunk_size = BUFFERSIZE-off-1;
int16_t char_written = 0;
int16_t char_in_buf = chunk_size < payloadlength ? chunk_size : payloadlength;
while (char_written < payloadlength) {
Serial.write((char*) Ethernet::buffer+off,char_in_buf);
char_written += char_in_buf;
char_in_buf = ether.readPacketSlice((char*) Ethernet::buffer+off,chunk_size,off+char_written);
}
nextSeq += ether.getTcpPayloadLength();
}
void setup () {
Serial.begin(57600);
Serial.println(F("\n[Persistence+readPacketSlice]"));
// Change 'SS' to your Slave Select pin, if you arn't using the default pin
if (ether.begin(sizeof Ethernet::buffer, mymac, SS) == 0)
Serial.println(F("Failed to access Ethernet controller"));
if (!ether.dhcpSetup())
Serial.println(F("DHCP failed"));
ether.printIp("IP: ", ether.myip);
ether.printIp("GW: ", ether.gwip);
ether.printIp("DNS: ", ether.dnsip);
if (!ether.dnsLookup(website))
Serial.println("DNS failed");
ether.printIp("SRV: ", ether.hisip);
}
void loop () {
static uint32_t timer = 0;
if (millis() > timer) {
timer = millis() + 7000;
Serial.println();
Serial.print("<<< REQ ");
ether.browseUrl(PSTR("/stories/"), "cmoutmou.txt", website, my_callback);
}
}