Siemens SIMATIC TIWAY 1 - Manual (Page 181)

USING THE NON-INTELLIGENT TERMINAL PROTOCOL
UNILINK HOST ADAPTER A–5
USER MANUAL
Then insert the character count at the beginning of the message body as
“00182001000202000E”. The ECC is given by:
Two’s complement
of (0018 + 2001 + 0002 + 0200 + 0E00) = CFE5 (ECC)
Fill Characters
so that the complete message is the character string:
:00182001000202000ECFE5;
or:
3A 30 30 31 38 32 30 30 31 30 30 30 32 30 32 30 30 30 45 43 46 45 35 3B
: 0 0 1 8 2 0 0 1 0 0 0 2 0 2 0 0 0 E C F E 5 ;
ASCII
CODES
CHARACTERS
The following table summarizes the NITP message structure:
Table A–2 NITP Message Structure
Field Contents No. of Characters
Beginning Delimiter Colon (:) 1
Character Count Hexadecimal 4
Body of Message Hexadecimal 580 (max.)
Error Checking Code Hexadecimal 4
Terminator Semicolon (;) 1
________
Total 590