Channel Initialisation

Overview

Controller module channel initialisation functions This group defines all functions to initialise controller channels properly.

Each measurement and control device that is attached to the labbCAN bus offers a number of controller channels.

Collaboration diagram for Channel Initialisation:

Functions
long	LCC_CreatePIDControlChannel (dev_hdl AnalogInput, dev_hdl Output, unsigned int LoopOutType, dev_hdl *pCreatedChannel)
	Function for creation of dynamic PID control channels. More...
long	LCC_GetChannelHandle (unsigned char Index, dev_hdl *pChanHdl)
	Get controller channel handle by its index. More...
long	LCC_GetNoOfControlChannels ()
	Query number of available controller channels. More...
long	LCC_LookupChanByName (const char *pChannelName, dev_hdl *pChanHdl)
	Lookup for a controller channel by its name. More...

Function Documentation

long LCC_CreatePIDControlChannel	(	dev_hdl	AnalogInput,
		dev_hdl	Output,
		unsigned int	LoopOutType,
		dev_hdl *	pCreatedChannel
	)

Function for creation of dynamic PID control channels.

With dynamic control channels you can create your own custom PID control loops. You just need to provide an analog input channel that measures the actual value and a control loop output for writing the control loop output value. You can use analog /digital output channels and pumps as control loop output. You can easily implement pressure controlled dosage by combining an analog pressure sensor as control loop input and a syringe pump as control loop output. The following example code shows how to do this

dev_hdl ControlLoopIn;
dev_hdl Pump;
dev_hdl ControlChannel;

LCAIO_GetInChanHandle(0, &ControlLoopIn);
LCP_GetPumpHandle(0, &Pump);
LCC_CreatePIDControlChannel(ControlLoopIn, Pump, PUMP_FLOW, &ControlChannel);

If you have created a channel, you need to call LCC_SetPIDParameter() to configure the PID parameters of the channel. If you have configured the PID parameters properly, you can enable the control loop via LCC_EnableControlLoop().

Parameters

AnalogInput	The control loop input - channel handle of an analog input device.
Output	The control loop output - you can pass in an analog out channel a digital out channel or a pump device.
LoopOutType	Provide the type of the loop output that should get created by this function. The type need to match the type passed in in Output parameter. The following types are supported: ANALOG A simple analog output - e.g. for controlling a heater DIGITAL A simple digital switch - e.g. for switching a heater DIGITAL_PWM A loop output that uses a digital output channel to create a PWM - e.g. for PWM control of a peltier element PUMP_FLOW A loop output that controls the flow rate of a pump (see LoopOutType for all output type identifiers)
pCreatedChannel	Returns the handle to controller channel handle if the channel was successfully created.

See also

LoopOutType for an enumeration of all loop output types

Returns

Error code - ERR_NOERR indicates success

Examples:

capi_dynamic_controller_test.cpp, and capi_pressure_control_test.cpp.

long LCC_GetChannelHandle	(	unsigned char	Index,
		dev_hdl *	pChanHdl
	)

Get controller channel handle by its index.

Parameters

[in]	Index	Index into list of available controller channels. The index must be in the range of 0 - (LCC_GetNoOfControlChannels() - 1)
[out]	pChanHdl	Returns handle to control channel or 0 if the given index is out of range

Return values

-ERR_PARAM_RANGE	If the given device index is out of range
ERR_NOERR	indicates success

Examples:

capi_qmixqplus_test.cpp.

long LCC_GetNoOfControlChannels

(

)

Query number of available controller channels.

Return values

>=	0 Number of available control channels
<	0 Error code

Examples:

capi_qmixqplus_test.cpp.

long LCC_LookupChanByName	(	const char *	pChannelName,
		dev_hdl *	pChanHdl
	)

Lookup for a controller channel by its name.

Parameters

[in]	pChannelName	The name to assign with this channel
[out]	pChanHdl	Handle to controller channel handle if the channel was sucessfully opened

Return values

-ERR_NODEV	No device with the given name found
ERR_NOERR	indicates success

Returns

Error code - ERR_NOERR indicates success

Examples:

capi_qmixqplus_test.cpp.