Charm Trigger

The Charm Trigger initiates a data transfer when new data is available on the Charm device. Unlike OPC Router 3, which provided the transfer object and trigger separately, both functions are now combined in the Charm Trigger object—meaning the trigger also serves as the data source.

The individual properties are:

Property	Description
Device Type	Type of Charm reader. The devices “EZ,” “EZ-M,” and “EZ-M 2” are predefined. However, you have the option to define additional device types using an XML file at .
Message Type	By default, “Message received” is set. When switching to “Heartbeat”, an internal device handles message reception in the background.
Port	Port on this computer (running the OPC Router) to which the Charm device sends its data. In general, a separate port must be created for each type of Charm device. Recommended approach: All Charm devices of the same type send data to the same port. A single connection is created for this purpose in the OPC Router. In addition to the results, the OPC Router also transfers information about the sending Charm device to the database. The logic for processing the results resides in the database (or another transfer destination). However, if a separate connection is to be created for each Charm device, a separate port must also be available for each device.
Available/Used Fields	Select the fields you want to use for your flow from the available fields. Use the arrows to confirm or cancel your selection.
Trigger transfer errors for invalid messages	Enable to trigger a transfer error for invalid messages. Disable to ignore invalid messages (for example, to intercept invalid messages in another connection using the Charm Error Trigger; see that section).

Confirm your entries by selecting “OK” (Confirm).

In addition to the message fields you selected from the available fields, further information about the received message is automatically displayed (message information). Under “Message Information,” the complete message, the IP address of the Charm device, the timestamp, and—in the case of multiple consecutive messages—a sequential numbering are displayed.

Message Information

Property	Description
Complete Message	The complete message from the Charm device
Client Address	IP address of the Charm device
Message Index	If multiple messages are sent simultaneously, the OPC Router numbers the individual messages.
Timestamp	Timestamp of the message (UTC)

note

In the Charm device, the IP address of the computer running the OPC Router must be specified along with the port number set here. The Charm device must send its data to this address. The OPC Router then performs the transfer of the data in individual records.

Fields of the predefined Charm device types

Name	EZ	EZ-M	EZ-M2	Description
Answer	X	X		Numerical test result including unit of measurement, where necessary
Assay	X	X		Sample type
ChannelNumber	X	X	X	EZ channel number
CommodityName		X	X	Raw material/Item
controlLINE	X	X	X	Control Line Intensity
CurrentCommoditySelectIndex		X
CurrentDilutionSelectIndex		X
CurrentMatrixSelectIndex		X
CurrentTestSelectIndex		X
Date	X	X	X	Date of test
DE_Name		X	X
Dirt	X	X	X	Degree of lens contamination
FailCode	X	X	X	Error code if test fails
Flow	X	X	X	Flow value (Correct application of milk to the test strip)
Interpretation	X	X	X	Interpretation of the test result (positive, negative, etc.)
InterpString	X			(Interpretation in newer firmware)
LotNumber	X	X		LOT number (as entered on the device)
MatrixNumber			X	Matrix number of the test result
Mode	X	X	X	Mode of the Charm device
OperatorID	X	X		Operator ID (as entered on the device)
Ratio		X	X	Ratio of extraction solvent to extraction
Remission	X	X
Result	X	X	X	Test result (positive, negative, invalid)
RFID			X
Sample ID	X	X	X	Test ID (as entered on the device)
StructVersion	X	X	X
testLINE	X	X	X	Test Line Intensity
TestOutputName	X	X	X
TestTemperature	X	X	X	Incubator-Temperature at the time of the test
TestType			X
Time	X	X	X	Time of the test
TipBlue	X	X		Displays value “Blue” when the test color has been identified
TipGreen	X	X		Displays value “Green” if the test color has been identified
TipRed	X	X		Displays value “Red”, if the test color has been identified
UnitSN	X	X	X
XLine	X	X	X	Intensity of the X line
YLine	X	X	X	Intensity of the Y line
ZLine	X	X	X	Intensity of the Z line

Interaction with the Charm remote station

The section on sequence diagrams explains how to read this diagram.

The Charm device establishes the TCP connection itself and keeps it open throughout the entire transfer. For the three device types provided—EZ, EZ-M, and EZ-M 2—the response containing the parse result is enabled in the device definition; the OPC Router therefore acknowledges the data set at the end with exactly one character: 'Y' if the transfer ends with Ok, Pending, or Forwarded; otherwise, 'N'. If the device definition also includes a checksum field, this transfer acknowledgment is preceded by a second, independent acknowledgment over the same channel—it evaluates only the checksum and provides no information about the transfer itself. The following diagram shows both return paths as well as the branch for a message that is already erroneous upon receipt and is routed to the error trigger.

The diagram shows that the connection established by the Charm device remains open throughout the entire transfer, and only the transfer result determines which individual character is sent back. The character stream is read until nothing else arrives for the duration of the Timeout parameter, which is preset to 5 s. The checksum acknowledgment occurs visibly before the transfer and constitutes a separate, independent exchange over the same line. The branch illustrates the error scenario: In this case, the router immediately responds with “N” and closes the connection; the transfer of the error trigger then proceeds without a return path to the device because the line is already closed.

Charm Trigger: The connection to the Charm device remains open throughout the entire transfer; only the transfer result determines whether the response byte is “Y” or “N.”