DNP3 Application Layer function codes

Confirm Function Code: Master sends this to a slave to confirm the receipt of an Application Layer fragment.

Read Function Code: Slave shall return the data specified by the objects in the request.

Write Function Code: Slave shall store the data specified by the objects in the request.

Select Function Code: Slave shall select (or arm) the output points specified by the objects in the request in preparation for a subsequent operate command. The Slave shall not activate the outputs until a request with a matching Operate function code is received.

Operate Function Code: Slave shall activate the output points selected (or armed) by a previous select function code command.

Direct Operate Function Code: Slave shall immediately actuate the output points specified by the objects in the request. A prior matching select command is not required.

Direct Operate—No Response Function Code: Same as function code 5 but Slave shall not send a response.

Immediate Freeze Function Code: Slave shall copy the point data values specified by the objects in the request to a separate freeze (or holding) buffer (or register).

Immediate Freeze—No Response Function Code: Same as function code 7 but Slave shall not send a response.

Freeze and Clear Function Code: Slave shall copy the point data values specified by the objects in the request into a separate freeze (or holding) buffer (or register). After the copy operation, clear the point data values to zero.

Freeze and Clear—No Response Function Code: Same as function code 9 but Slave shall not send a response.

Freeze at Time Function Code: Slave shall copy the point data values specified by the objects in the request to a separate freeze (or holding) buffer (or register) at the time and/or time intervals specified in a special time data information object.

Freeze at Time—No Response Function Code: Same as function code 11 but Slave shall not send a response.

Cold Restart Function Code: Slave shall perform a complete reset of all hardware and software in the device.

Warm Restart Function Code: Slave shall reset only portions of the device.

Enable Unsolicited Responses Function Code: Enables Slave to initiate unsolicited responses from points specified by the objects in the request.

Disable Unsolicited Responses Function Code: Prevents Slave from initiating unsolicited responses from points specified by the objects in the request.

Assign Class Function Code: Slave shall assign the events generated by the points specified by the objects in the request to one of the classes.

Delay Measurement Function Code: Slave shall report the time it takes to process and initiate the transmission of its response. This allows the master to compute the propagation delay in the communications channel. Used for non-LAN time synchronization.

Record Current Time Function Code: Slave shall save the time when the last octet of this message is received. Used for LAN time synchronization.

Open File Function Code: Slave shall open a file.

Close File Function Code: Slave shall close a file.

Delete File Function Code: Slave shall delete a file.

Get File Information Function Code: Slave shall retrieve information about a file.

Authenticate File Function Code: Slave shall return a file authentication key.

Abort File Function Code: Slave shall abort a file transfer operation.

Activate Configuration Function Code: Slave shall use the configuration specified by the objects in the request.

Solicited Response: Master shall interpret this fragment as an Application Layer response to an Application Layer request sent by the master.

Unsolicited Response: Master shall interpret this fragment as an unsolicited response that was not prompted by an explicit request.