mcDAQStartStop
- Updated2025-09-25
- 2 minute(s) read
Purpose
Starts or stops the transmission of the DAQ lists assigned to the Measurement task on the ECU. Format
| mcTypeStatus |
mcDAQStartStop(
|
Input
DAQRefNum
DAQRefNum is the task reference from the previous Measurement task function. The task reference is originally returned from , and then reused by subsequent Measurement task functions.
StartStopMode
StartStopMode indicates the type of function to be performed.
0—mcStartStopModeStop
Configures the ECU to stop transmitting a DAQ task. If stopped, properties of the DAQ task can be changed using . This function is performed automatically before .
1—mcStartStopModeStart
Configures the ECU to start sending data for a Measurement task. Ensure that the DAQ list has not yet been transferred to the ECU first. Once started, properties of the DAQ list can no longer be changed using . This function is performed automatically before the first read of the DAQ list with .
2—mcStartStopModeTransmitDAQ
Transfers the DAQ list to the ECU, but does not start it. For example, use this mode if you want to change the session status before starting the DAQ list. For some ECUs this is necessary.
3—mcStartStopModePrepareStartAll
Prepares a DAQ or STIM list to be started by a single command. This is useful when multiple DAQ or STIM lists are used with the same ECU. After preparing the DAQ or STIM lists with this command, use mcDAQStartStop with mode mcStartStopModeStartAll to start all lists at the same time.
4—mcStartStopModeStartAll
Starts all previously prepared DAQ or STIM lists at the same time with a single command.
5—mcStartStopModeStopAll
Stops all running DAQ or STIM lists on the same ECU with a single command. Output
Return Value
The return value indicates the status of the function call as a signed 32-bit integer. Zero means the function executed successfully. A negative value specifies an error, which means the function did not perform the expected behavior. A positive value specifies a warning, which means the function performed as expected, but a condition arose that may require attention.
Use the function of the ECU M&C API to obtain a descriptive string for the return value.
Descriptionis an optional command to start or stop communication for an M&C Measurement task. If you do not perform (with the parameter mcStartStopModeStart) before using the Measurement task is started by the first call of . After you start the transmission of the DAQ lists, you can no longer change the configuration of the Measurement task with . You must call (with the parameter mcStartStopModeStop) first.