I can get the MAC by MacInfo=MACID();
But I dont know the data type of mac, how can I change it to string or text ? use BuffToArray or other func ? thank you.

str = BuffToArray(data[0],
6 ,
MacInfo[1][0] ,
0 ,
5 ,
1,
0 { Don't skip anything });

Have a look at the help file links below on ValueType and Cast:

ValueType: https://www.vtscada.com/help/Content/Pro_Functions/ValueType.htm

Cast: https://www.vtscada.com/help/Content/Pro_Functions/Cast.htm

@Dave - VTScada
Thank you. But I haven`t got the result I wished. Whoud you like to give me a demo that show the MAC with ZText function ?

The MAC is a string of binary values. You can use BuffToHex to convert it to hex characters, e.g.

TextMac = \System.BufftoHex(Mac[1][0]);

If you want to format it to be more readable, e.g. with ":" separators, then either loop around the bytes or break then out separately, e.g.

TextMac = BuffStream("");
SWrite(TextMac, "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x",
                GetByte(Mac[1][0], 0), GetByte(Mac[1][0], 1),
                GetByte(Mac[1][0], 2), GetByte(Mac[1][0], 3),
                GetByte(Mac[1][0], 4), GetByte(Mac[1][0], 5));

@Graham Bloice Thank you very much.