Controlling oscillography data through the main port is based on the relay itself. Whenever there is oscillography data marked as unread on a relay, indicated by the bit 5 (five) of the status byte, it is loaded by this Driver. A relay indicates unread disturbances by a negative number, iCellMin, and read oscillography data go up to a maximum positive number, iCellMax, limited by the memory of a device. The values of Tags with the N2 parameter equal to 328 (current disturbance) and equal to 329 (largest disturbance) are defined by the next calculation:

  m_sRecordNumber = iCellMax;
  m_wMaxFaultNumber = iCellMax - iCellMin;

When this Driver is communicating using the secondary port, there is a cyclic verification of all existing oscillography data, starting at iCellMax and decrementing down to iCellMin, comparing with the time of the last oscillography data collected, which can be configured by a Tag with the N2 parameter equal to 324. A similar operation occurs for events when this Driver communicates using the secondary port.

In case of receiving a request from a busy relay, this Driver tries to communicate with another relay and then return to that first one, depending on internal conditions.

To extract oscillography data from relays that use a compressed format, there is a need that exists , together with this Driver or on C:\Windows\System32 directory or equivalent, the file Cvt2Ctrd.dll, which executes a decompression of this oscillography data on the requested directory.

When reading cells by polling, usually the protocol's informed data type is the Tag's data type. For the DTL_NUM (0x2C) and DTL_XNUM (0x30) data types, data returned is a text composed by the value of the Tag plus the unit.

There is a sequence of operations to extract an oscillography record. Starting with the bit 5 (five) of the status word, if active, also checking whether oscillography collecting is not suspended or disabled, or whether the last collecting was already stored on disk, perform the next procedures:

1.Read cell CONTROL_COLUMN to discover the control cell for disturbances (XX00).

2.Read cell EXTRACTION_COLUMN to discover the control cell for extraction (YY00).

3.Execute command Enter Setting Mode YY01, retrieving the limits of the cell based on the difference between iCellMin and iCellMax.

4.Execute command Preload Setting YY01 with value 0 (zero).

5.Execute command Setting YY01.

6.Read cell YY0A to retrieve the compression format. If the compression format is equal to 0 (zero):

1.Read cells YY02, YY03, YY04, YY10, YY11, and YY12.

2.Read text from cell YY03.

3.Read cell YY20 plus the digital channel.

4.Read cell YY13. If it does not exist, read cell YY14.

5.Read the configuration of analog channels, from YY05 to YY09.

6.Read data from channels (YY20 + channel).

7.If the compression format is equal to 1 (one):

1.Read cell YY02.

2.Read data from cell YY0B.

8.Execute command Reset Cell YY01.

Even if this Driver is not communicating in Serial mode, it uses the baud rate informed as the base for idle time between two consecutive communications.