Details of the DNP3 Driver
This chapter is dedicated to advanced WinCC OA users. It describes the debug levels and provides information about the DNP3 driver.
Debug Levels
The following command line options can be used for identification a possible source of error. Enter -helpdbg to display more information about other options.
| Debug | Debug level | Description |
| DEBUG_WORK | -dbg 2 | General debug information. |
| DBG_API_USR1 | -dbg 10 | Debug information about establishing, disconnecting and monitoring of the connection. |
| DBG_DRV_WORK | -dbg 24 | Additional general debug information. |
| DEBUG_DRV_USR1 | -dbg 25 | Debug information concerning sent telegrams. |
| DEBUG_DRV_USR2 | -dbg 26 | Debug information concerning received telegrams. |
Transformations
A transformation converts hardware data into a WinCC OA format. The transformation type of a data point element can be requested and set via integer constants. Using dpGet() or dpSet(), the attribute _address.._datatype must be used, too. For detailed information about the integer constants, which are used for the DNP3 driver transformations, see chapter _address.
Freezing counters
This section describes how counters in a station can be frozen. For this purpose an output address must be configured for a data point element of type unsigned. Define the group "Counter" (20) as well as the corresponding index of the counter to freeze. The value of the corresponding data point element is not relevant and is only used to trigger the freezing of the counter. Use the function in the peripheral address (see Defining the Peripheral Addresses of the DNP3 Driver) to specify how the freezing shall be done. Following function codes are available:
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7: freeze
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8: freeze with no acknowledgement
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9: freeze and clear
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10: freeze and clear with no acknowledgement
Error messages
If an exception telegram has been received or sent, the error codes of the DNP3 driver are used and committed to the WinCC OA log viewer. The error message is automatically written into the WinCC OA log file and WinCC OA log viewer.
Polling
In order that the performance during polls may not be influenced, not all addresses can be read individually.
General Query
With the config entry integrityPollAtStartup the general query during a connection establishment can be deactivated/activated.
Normally polling is not used when using the DNP3 driver, since applying polling can result in poor performance under certain circumstances. An unsolicited data transfer or a single request will be carried out in this case.
