The Win-Test Protocol¶

The Win-Test protocol is based on UDP broadcast packets, by default sent to the local broadcast address at port 9871.

There is some partial documentation of the Win-Test protocol here: http://download.win-test.com/utils/SummaryBroadcastingSpecs.txt

This protocol documentation was made by reading the documentation above, and by reverse engineering the protocol using Wireshark and python code.

The resulting documentation, python code and everything else related to this project has no affiliation with the Win-Test developers. It has been created out of personal curiosity and is presented in the hope that it may be useful or at least amusing to others.

Any further insights and/or corrections to this project is greatly appreciated. Please get in touch via https://github.com/hin/aiowintest

Payload structure¶

The payload structure is mostly an ASCII-encoded string followed by a checksum and an optional null-character.

The structure of the payload is as follows:

field	type
frame_type	string
:	colon delimiter (ascii 58)
space	space delimiter (ascii 32)
from_station	string
space	space delimiter (ascii 32)
to_station	string
space	space delimiter (ascii 32)
data[0]	data field
space	space delimiter (ascii 32)
data[1]	data field
space	space delimiter (ascii 32)
…
data[n]	data field
checksum	byte
null	null character with unknown purpose (optional)

For some packets, the payload also contains a null (0x00) character at the end. According to the limited protocol documentation I’ve found, it should not be there, and I’ve not been able to find any purpose of it. It may simply be a bug in the Win-Test software.

For now, I check for the extra null character and ignore it if it exists.

Checksum calculation¶

When sending a packet, the checksum is calculated as:: (sum of all bytes) | 128 % 256

In python, this can be calculated as:

def checksum(data):
    return (sum(data)|128)%256

Data field format and encoding¶

The data fields in the payload are either strings enclosed in quotes (ascii 34) or integers encoded as decimal strings without quotes.

If a string contains the quote character, it is escaped with a backslash (ascii 92).

Win-Test seems to accept iso8859-1 and any character code above 127 is encoded as a backslash followed by the character code in octal.

For example, the string åäö” is encoded as:

original character	encoded characters	ascii code
å	backslash,3,4,5	92,51,52,53
ä	backslash,3,4,4	92,51,52,52
ö	backslash,3,6,6	92,51,54,54
“	backslash,”	92,34

Frame types¶

The frame_type field in the packets specifies what kind of information the packet contains. I have not found a list of all the frame types so this document contains what can be found in the official docs, as well as the packets I’ve encountered while reverse engineering the protocol.

Frame Type GAB¶

Gab messages are the chat messages that can be sent between stations. Apart from the from_station and to_station, it only contains one data field, which contains the actual text of the gab message.

The to_station is a zero length string in the case of a gab message that is sent to all stations.

Frame Type SUMMARY¶

This packet contains information about the score status of the contest. It is described in detail in the official document linked to above.

Frame Type RCVDPKT¶

RCVDPKT is used to broadcast DX cluster spots coming from the telnet connection. The from_station is ‘TELNET’ and the to_station is an zero length string. There is one data field which is formatted as it arrives over telnet from the DX cluster.

Frame Type STATUS¶

Sent regularly, and contains the following data fields:

type	information
int	unknown
int	unknown
int	unknown
int	unknown
int	VFO A frequency in 100s of Hertz
string	unknown
int	unknown
string	unknown
int	VFO B frequency in 100s of Hertz
string	operator callsign

Frame Type TIME¶

Used for time syncronization. The to_station field is empty, and the only data field is a number representing seconds since the Unix Epoch.

Frame Type IHAVE¶

The purpose of this message, which is sent quite frequently, is unknown.

It seems to contain some numbers that could possibly be used to synchronize Win-Test instances in the case where UDP packets are lost, but this is just a guess. More investigation is needed.

Frame Type ADDQSO¶

This message is sent when a QSO is entered by the operator.

The data fields are as follows:

type	information
int	timestamp in unix time
int	frequency in 100s of Hertz
int	unknown
int	unknown
int	unknown
int	unknown
int	unknown
int	unknown
int	unknown
string	callsign of worked station
string	sent report (e.g. “59”)
string	received contest exchange (e.g. “5904”)
string	unknown
string	unknown
string	unknown
int	unknown
string	unknown
string	unknown
string	operator callsign
int	unknown