Appendix 4
Data Format To Netiom-UDP
The basic format of the message without a serial output string is:
[Identifier][Message Type][Message Number][Output Data]
where:
Identifier is fixed and must be
NetiomUDP
. This is to prevent other network devices using the
same port number causing data to be written to the outputs inadvertantly.
Message Type is a single character and may be:
‘A’ indicates that the data is a regular update to which Netiom-UDP will not send an
acknowledgement. Normally this type of message is used as a heartbeat to indicate that the
link is still established. If the data has changed then Netiom-UDP will still update the outputs.
‘U’ indicates that new data is present and that an acknowledgement is requested. In this case
Netiom-UDP will reply with the current status on inputs and outputs.
‘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
acknowlaged.
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. If a type ‘R’ message is sent it should use the
Message Number of the previous message. Note that a value of zero should be avoided for
the message number.
Output Data is a 16 character string which represents the state of the outputs. Output 1 is the
first character of the string while output 16 is the last. A ‘1’ indicates that the output is on, a ‘0’
indicates that the output is off and a ‘*’ indicates that the output should remain unchanged.
Example:
NetiomUNPA~1100************
Will turn outputs 1 and 2 on. outputs 3 and 4 off and leave all others unchanged. No response
will be returned from Netiom-UDP.
The basic format of the message with a serial output string is:
[Identifier][Message Type][Message Number][Output 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 to be sent
via the serial port
Data is the serial string to be sent. This can be in any format.
