DM2_Read (FB)¶

FUNCTION_BLOCK DM2_Read EXTENDS DM1_Read

This function block reads DM2 messages from a given device (itfSourceECU) as long as xEnable is TRUE. In principal a DM2 message contains lamp information and all previously active diagnostic trouble codes (DTC). Following information is provided by this function block:

Lamp information for following lamps:
- Malfunction Indicator Lamp(MIL)
- Red Stop Lamp (RSL)
- Amber Warning Lamp (AWL)
- Protect Lamp
Number of previously active DTCs(output: udiDTCCount)
Information about if DM2 message was received in the current PLC cycle (xReceived).

For detailed information about received DTC data one or more DTC Handlers can be connected with this function block (optionally). For example:

DTCBufferWriter: Writes DTC data to a given memory buffer
DTCLogger: Writes DTC data to the PLC log.

InOut:

Scope	Name	Type	Initial	Comment	Inherited from
Input	`xEnable`	`BOOL`		`TRUE`: Action starts `FALSE`: Action stops, outputs `xDone`, `xBusy`, `xError` are resetted	LTrig
Output	`xDone`	`BOOL`		`TRUE`: Action successfully completed	LTrig
	`xBusy`	`BOOL`		`TRUE`: Function block active	LTrig
	`xError`	`BOOL`		`TRUE`: Error occurred, function block aborts action `FALSE`: No error	LTrig
Input	`itfSourceECU`	`IJ1939RemoteECU`		ECU which sends this message	DM1_Read
Output	`itfDTCHandlerList`	`IDTCHandlerList`	THIS^	mainly for graphical programming: output for optional connection to DTC Handler	DM1_Read
	`udiDTCCount`	`UDINT`		Contains number of received Diagnostic Trouble Codes.	DM1_Read
	`MalfunctionIndicatorLamp`	LAMP_INFO		Malfunction Indicator Lamp: Lamp to indicate when there is an emission related trouble code active.	DM1_Read
	`RedStopLamp`	LAMP_INFO		Red Stop Lamp: Lamp to indicate a problem that is severe enough to warrant stopping the vehicle.	DM1_Read
	`AmberWarningLamp`	LAMP_INFO		Amber Warning Lamp: Lamp to indicate a problem with the vehicle system but the vehicle does not need to be stopped immediately.	DM1_Read
	`ProtectLamp`	LAMP_INFO		Protect Lamp: Lamp to indicate a problem with a vehicle system that is most likely not electronic subsystem related (e.g. Coolant Temperature has exceeded its defined range.)	DM1_Read
	`xReceived`	`BOOL`		If a DM message was received xReceived is TRUE for one cycle.	DM1_Read
	`eError`	ERROR		detailed error information if xError is TRUE	DM1_Read