Assigning Initial values to an array in a struct

Projects Programming
1

Hi All,

I am new to Arduino and to C but am learning fast.
I have a question, however, about initialising a struct.
The following code works:

const short rom_net_cfg = 128; //Start Address for Network Configuration Storage

struct NET_t
{
byte MyMac[6];
byte MyIP[4];
byte ServerIP[4];
byte ServerSN[4];
short MyPort;
short ServerPort;
} LAN;

but I then need to initialise it.
is there a shorter way than:

LAN.MyMac[0] = 0x02;
LAN.MyMac[1] = 0x00;
LAN.MyMac[2] = 0x01;
LAN.MyMac[3] = 0x00;
LAN.MyMac[4] = 0x00;
LAN.MyMac[5] = 0x00;

LAN.MyIP[0] = 10;
LAN.MyIP[1] = 0;
LAN.MyIP[2] = 0;
LAN.MyIP[3] = 191;

etc.

The Reason it is a struct is that several of them will be passed around the network and also stored and retrieved from EEPROM using EEPROM_readAnything(rom_net_cfg, LAN);

Thanks for any insight.

Cheers
Chris

2 
struct NET_t
{
   byte   MyMac[];

Doesn't the compiler complain about that?

3

try something like this.

struct NET_t
{
   byte   MyMac[]; 
   byte   MyIP[];   
   byte   ServerIP[];
   byte   ServerSN[];
   short  MyPort;             // should be an uint16_t myPort  !!! range = 0..65535
   short  ServerPort;        // idem
} LAN =
{
  { 0xDE, 0xAD, 0xBE, 0xEF, 0x00, 0x01 },
  { 192,168,1,200 },
  { 192,168,1,2 },
  { 192,168,1,200 },
  { 192,168,1,200 },
  50,
  8080
}
4

Or with a chance of compiling:

struct NET_t
{
   byte   MyMac[6]; 
   byte   MyIP[4];   
   byte   ServerIP[4];
   byte   ServerSN[4];
   short  MyPort;             // should be an uint16_t myPort  !!! range = 0..65535
   short  ServerPort;        // idem
} LAN =
{
  { 0xDE, 0xAD, 0xBE, 0xEF, 0x00, 0x01 },
  { 192,168,1,200 },
  { 192,168,1,2 },
  { 192,168,1,200 },
  50,
  8080
};
5

@AWOL - no it didn't :slight_smile: But I noticed and corrected it.

@robtillaart - Thanks for the Quick replays.

@AWOL again, you replied whilst I was testing.
Thanks a ton your code worked perfectly :slight_smile:

And I have learn 3 things:

How to initialise a structure,
Don't be scared to ask,
and that you guys are a great bunch :slight_smile:

Thanks you both,
Cheers
Chris