Siemens SIMATIC TIWAY 1 User Manual page 182

USING THE NON-INTELLIGENT TERMINAL PROTOCOL
Figure A–2 illustrates how a TIWAY I Primitive is enclosed in the adapter
command string which is enclosed in the NITP message structure.
Primitive Descriptor Data Unit
Length
Code Field(s) Field(s)
TIWAY I Primitives
Secondary
Command Code Network Data
Address
UNILINK Host Adapter Commands
Message
Adapter Data
: Check Sum ;
Character
Count
NITP Protocol Message Frame
Figure A–2 Illustrative NITP Message Structure
UNILINK HOST ADAPTER A-6
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