La Crosse Technology WS-2510, Руководство по эксплуатации

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Data formats
Data transfer: 19,200 Baud, Even Parity, 8 Bit, 2 Stop
Data frames for commands from the PC to the PC radio interface
<SOH> <Comm> [Para] <Test> <EOT>
<SOH> is the start symbol of the data transfer
<Comm> is the command for the interface
[Para]
are any parameters that may arise. For the parameters, Bit 7 is always
set (so that they are not recognised as functional characters)
<Test> is the negative test total, reached by entering the command and the
following parameter.
Bit 7 is always the value set here.
(if, for example, the command has the value 31h, then Test must
have the value CFh).
<EOT> is the end symbol of the data transfer
Data frame for responses from the interface:
<STX> <length> [message] <test total> <ETX>
The start symbol transmitted will be <STX> while the end symbol will be <ETX>
All symbols between the start and the end will be processed in such a way that
no <STX> and no <ETX> occur.
<STX> becomes the symbol series: <ENQ> <DC2>
<ETX> becomes the symbol series: <ENQ> <DC3>
<ENQ> becomes the symbol series: <ENQ> <NAK>
• After a data package has been received, this editing must first be cancelled
before the length and the test total can be checked.
• From the length you can derive the number of characters in the message.
• The test total is the negative 8-bit total of the number of bytes from <STX>
up to the last character of the message. If all of the characters are added up
(from STX to the test total), then the bottom 8 bits must yield the total 0.
In the case of incorrect data reception, the interface will send the message
<NAK>.
<STX> <01h> <NAK> <0E8h> <ETX>
Hex : 02 01 15 E8 03
Note: In the following description of the individual commands, only the actual
message will be given as a response. The data frame is still to be added.