Appendix 5
Data Format From Netiom-UDP
The basic format of the message without a serial output string is:
[Identifier][Message Type][Message Number][Digital Input Data][Output Data][Analogue Data]
where:
Identifier is fixed and is always
NetiomUDP
.
Message Type is a single character and may be:
‘A’ indicates that the data is a regular update to which Netiom-UDP will not expect an
acknowledgement. Normally this type of message is used as a heartbeat to indicate that the
link is still established.
‘U’ indicates that new data is present and that an acknowledgement is requested.
‘C’ indicates that the message was generated in response to a ‘U’ type message.
‘R’ indicates that the message is a resend because a previous ‘U’ type message has not been
acknowledged.
Message Number is a single binary byte and is used to ensure that type ‘R’ messages do not
send multiple strings over the serial port. Normally this value is incremented (and allowed to
roll over) for each non ‘R’ type message. When a type ‘R’ message is sent it uses the
Message Number of the previous message. Note that a value of zero is never sent.
Digital Input Data is a 16 character string consisting of ‘1’s and ‘0’s followed by a comma
representing the states of the inputs.
Output Data is a 16 character string consisting of ‘1’s and ‘0’s followed by a comma
representing the states of the outputs.
Analogue Data is a 4 field comma delimited string. Each of the fields is an ASCII number up
to 4 characters representing the value on an Analogue Input. Input 1 is reported first.
Example:
NetiomUDPA~1100110011001100,1111000011110000,123,456,99,1024
The basic format of the message with a serial output string is:
[Identifier][Message Type][Message Number][Digital Input Data][Output Data][Analogue Data]
[Serial Identifier][Number of Characters][Data]
where
Serial Identifier is the character ‘S’ and indicates that the message contains serial data.
Number of Characters is a single binary character with the number of characters received via
the serial port
Data is the serial string to be sent. This can be in any format.
