User guide

3: Packet Formats
DC 900-1303C 49
3.2 Freeway Control Packet Formats
Each Freeway control packet contains a TSI header and a Freeway header. Optionally, a
Freeway control packet can contain data immediately following the Freeway header.
The Freeway control packet is a type of TSI data packet.
3.2.1 Open Session Request Packet
The Open Session request consists of a TSI header, Freeway header, and an ASCII char-
acter string specifying the ICP the client wants to communicate with during this ses-
sion. The string must match a device name in the server Boot Configuration file.
a
sequence number assigned by client
a
id assigned by client
a
normally, this is icpn, where n = 0,1,2...
TSI Header
Header Length = 20
Data Length = 44+data
Sequence Number = n
a
Packet Type = 2
Command = n/a
First Segment = n/a
Last Segment = n/a
Freeway Header
Reserved
Shared Header Size = 12
Private Header Size = 20
Type = 1
Command = 1
Status = n/a
Client Session ID = n
a
Freeway Session ID = n/a
Reserved
Private
Data
ICP Device Name
a
(1-45 chars)