K-Patents PR-23 - Manual (Page 180)

172 PR-23 instruction manual
ware on your computer. One solution is to get the software package from K-
Patents. The package contains a ready-to-use data acquisition program for Win-
dows 2000/XP/Vista.
However, if you need a tailored system, you can also program a downloading facil-
ity yourself following the specifications below.
Note: K-Patents guarantees that the specifications are correct, but cannot as-
sume any responsibility or provide support for other software than the unmod-
ified K-Patents software.
12.5.1 Communication protocol
The communications protocol is based on UDP/IP to port 50023. It is a
client/server protocol, where the DTR is the server and thus only sends informa-
tion when the client (i.e. your computer) requests it. The server should answer to
all requests within five seconds (5000 ms) from the request, usually the response
time is below 100 ms.
Request format
The client to server communication, i.e. the requests sent from your computer to
the DTR, is in binary format. The request packets contain the following binary data
(all integers are in the network order, MSB first):
− 32-bit integer: packet number
− 32-bit integer: request ID
− (any): request data (depends on the request)
− (any): fill-in data
Important: The maximum size of the message is 1472 octets (bytes).
The packet number is echoed back by the DTR, but not processed in any way. The
packet numbers do not have to be sequential, any 32-bit value is valid.
The request ID is a 32-bit value that identifies the requested function, for example
sensor information. See Section 12.5.2 for request IDs.
The request data consists of 0 to 1464 octets of additional data associated with
the request.
The fill-in data can be used to increase the number of octets in a message. Any
number of NULL characters (0x00) may be added to the end of the request as long
as the total size of the message does not exceed the maximum of 1472 octets. This
may be useful, for example, if the client implementation uses fixed-length packets.