Knowledge Base / Protocols / DF1

I am using a ProSoft DFCM solution (or possibly another DF1 protocol product) and I am having problems establishing and/or maintaining communications with a node that his been assigned Station Number

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The number 16, or 10hex, is a special number in the protocol.  This number is used as an 'attention' character, as special control character that alerts DF1 receivers that a command message or response is following.

DF1 protocol messages can be long and complex.  In some sections of the message, a value of 10hex will be assumed to be a control character and in other sections, it will be assumed to be just another data value.  If a Slave is assigned Station Number 16, it puts a special burden on the protocol firmware to recognize when 10hex is a control code, when it is a station number, and when it is just data.  The protocol specification makes special provisions for how to handle 10hex values; but not all protocol implementations follow the specifications closely enough to prevent problems.

If you are using DF1 to try to communicate with DF1 Station Number 16 and you experience intermittent or failing communications, you could ask the device manufacturer to examine how their firmware handles the Station Number 16 issue and whether or not they are following the DF1 protocol specifications correctly.

An easier way to deal with this problem is to simply not use 16 (10hex) as a Station Number for any nodes on your DF1 network.