User guide

2: Freeway Client-Server Protocol
DC 900-1303C 33
Packet Type (2 bytes)
This field indicates the type of packet. There are two distinct types of packets
under the TSI. One is the control packet, and the other is the data packet. If the
control packet is used, the Command field is significant. Otherwise, the Com-
mand field is ignored. Valid packet types are:
Control packet (1)
A control packet is a packet that is received, validated, and processed by the
TSI. A control packet always produces a control response packet unless it is
an acknowledge packet (ACK or NAK). No control packet is passed on to
the application. Some control packets may have addition data in the data
area.
Data packet (2)
A data packet is a packet that is received and validated by the TSI. The data
packet is subsequently delivered to the TSI user unless the connection no
longer exists.
Command (2 bytes)
This field is only significant if the packet is a control packet. Valid commands are:
Bind (1)
The Data Length field should indicate the size of the Bind request. Currently
the data field is 10 bytes.
Unbind (2)
There is no data area accompanying this packet and the Data Length field
must be 0.
Unbind force (3)
There is no data area accompanying this packet and the Data Length field
must be 0.