the page is held in the host computer - the ENC28J60 is just an Ethernet controller
#define MY_MAC_ADDRESS "00-1c-7e-85-fd-af" // set board to this MAC address
setMACaddress(MY_MAC_ADDRESS, &AppConfig.MyMACAddr);
ain addition to an RTC and EEPROM the MCP79411/12 has EUI-48/64 in ROM
// I2C device address
static const int address = 0xa0;
unsigned char MACaddress[8]={0};
// read MCP79410 EUI-48 or EUI-64 node identy
int MCP79410readMACaddress(int display)
{
// MAC address is at EPROM address FAhex
unsigned char data[10] ={0}, check[3]={0, 0x4,0xa3}; // read from 0xfa
int i;
if(display)printf("\nread MCP79411 serail EEPROM with EUI-48/64 node identy\n");
// read the MCP79411/12 ID 48 or 64 bit
MCP79410readEEPROMbyte(0xf0, data, 8); // read the EUI node identy
// if node ID does not exist return otherwise set it up
for(i=0;i<8;i++) MACaddress[i]=data[i];
if(display)
{
printf("read MAC address MCP79411 EUI-48/64 node identy ");
for(i=0;i<8;i++) printf("%02x ", MACaddress[i]);
if(memcmp((void *) data, (void *)check, 3))
{ printf(" ERROR !! EUI node ID incorrect!\n\r"); return 0; }
else printf(" - OK!\n\r");
}
//printf("\n");
// memcpy((void*)&AppConfig.MyMACAddr, (void*)data, sizeof(AppConfig.MyMACAddr));
return 1;
}the original Ethernet, where stations were multi-dropped from a shared cable and used a contention protocol for access, were half-duplex, i.e. only one station could transmit at a time.