Chapter 9 Ethernet Specification and Operation
9-67
Data Type Description
UNSIGNED
INTEGER
USINT(1 byte), UINT(2 bytes), UDINT(4 bytes), ULINT(8 bytes)
Ex: UDINT value = H’AABBCCDD
Number 1st 2nd 3rd 4th
UDINT DD CC BB AA
STRING
ASCII CODES, 1 or 2 bytes/words
STRING: 2 bytes character count + 1 byte character
Contents (Char count) Contents (String contents)
STRING 04 00 4D 69 6C 6C
STRING2: 2 bytes character count + 2 byte character
Contents (Char count) Contents (String contents)
STRING2 04 00 4D 00 69 00 6C 00 6C 00
SHORT_STRING: 1 bytes character count + 1 byte character
Contents (Char count) Contents (String contents)
STRING 04 4D 69 6C 6C
Fixed LENGTH
BIT STRING
BYTE (1 byte), WORD (2 bytes), DWORD (4 bytes), LWORD (8 bytes)
1st 2nd 3rd 4th 5th 6th 7th 8th
Byte 7…0
WORD 7…0 15…8
DWORD 7…0 15…8 23…16 31…24
LWORD 7…0 15…8 23…16 31…24 39…32 47…40 55…48 63…56
STRINGI
A single string consists of multiple language representation
Name Data Type Meaning
Number USINT
The number of internationalized character
strings
Strings
Array of:
Struct of:
Array of individual internationalized character
strings
LanguageChar1 USINT
The first ASCII character of the ISO 639-2/T
language