Inheritance diagram for VIB::Strobe:

Detailed Description

This class controls the LED Strobe Controller.

The LED strobe controller is designed as a current source. It allows generation of pulses with programmable duration and current value.

The following schematic shows a simplified strobe output:

VisionBox / VisionCam with integrated LED controller

For a detailed electrical specification please take a look into the hardware manual.

The typical workflow for programming the Strobe Unit with this API is as follows:

Initialize the Strobe Unit by using Init()
Use SetLimits() or SetFixedCurrent() to set the operating conditions
Set the strobe output parameters: SetCurrent() / SetOnTime()
Set the trigger mode to hardware or software trigger, using edge or level (copy) signals => SetTriggerMode()
When using hardware trigger, configure the trigger source with SetTriggerSource()
In edge triggered mode set the trigger delay with SetTriggerDelay()
In hardware triggered mode, the strobe unit is ready and can be used
In software triggered mode, the function SwTrigger() can be used to activate the output

Note: The strobe unit will be deactivated when closing the device object.

Example code

// open the Strobe device
VIB::Strobe strobe;
if (!strobe.Open(0))
    return -1;
 
//internal initialization, reset all strobe settings
if (!strobe.Init(true))
    goto error;
 
//set information about your light
int minOffTime;
if (!strobe.SetFixedCurrent(
    24,             // Supply voltage: 24 V
    20,             // Load voltage: 20 V
    300,            // Maximum ON time: 300 µs
    0,              // Minimum OFF time: allow steady ON state if possible
    1000,           // Current: 1 A
    minOffTime))    // the calculated minimum off time [us]
    return -1;
 
printf("Minimum OFF time: %d us\n", minOffTime);
 
//set duration time to 1 ms
if (!strobe.SetOnTime(1000))
    return -1;
 
//set the trigger mode to software (one)
int NewTriggerMode;
if (!strobe.SetTriggerMode(VIB::Strobe::STROBE_MODE_SOFTWARE_EDGE, NewTriggerMode))
    return -1;
 
// trigger strobe by software
if (!strobe.SwTrigger(1))
    return -1;
 
// ...

Operating conditions

The internal calculations of this API ensure that the hardware will not be damaged by overload. These calculations are based on the operating conditions given to SetLimits() or SetFixedCurrent():

Supply voltage for the Strobe Unit
Load voltage while the output is active with the maximum allowed current
Maximum ON-time to be used
Minimum allowed OFF-time between pulses
Maximum allowed output current for SetLimits() or fixed current for SetFixedCurrent()

Warning: In the case of wrong parameters the hardware can be damaged!

For VisionBox / VisionCam hardware with integrated LED controllers, the supply voltage for the strobe unit is equal to the power supply voltage used.

With the information provided to the functions, the library calculates the allowed parameters for maximum allowed output power. When using SetLimits(), the parameter LimitCurrent specifies if the API should limit the minimum allowed OFF-time between pulses, or if the current will be adjusted to avoid overload. SetFixedCurrent() will always limit the minimum OFF-time.

During operation, the FPGA ensures that the maximum ON-time is not exceeded and that the minimum OFF-time is not undercut. Trigger signals will be ignored under such conditions.

The following calculator can be used to estimate the results for SetFixedCurrent() and SetLimits() depending on the hardware and operating conditions:

Calculator

Hardware:
SupplyVoltage:	V
LoadVoltage:	V
MaxOnTime:	µs
MinOffTime:	µs (use 0 to allow steady ON state)
Current:	mA
SetFixedCurrent():	Min. OFF time:	Code: `SetFixedCurrent(...)`
SetLimits(0, ...):	Min. OFF time:	Code: `SetLimits(...)`
SetLimits(1, ...):	Max. current:	Code: `SetLimits(...)`

Maximizing output power

A lower difference between the supply voltage and the maximum load voltage reduces power losses. Make sure that the values given to SetLimits() are close to real values. If the difference between both values gets smaller than reality, the hardware can be damaged!
If the difference between the supply voltage and the load voltage is small, set a fixed operating point by using SetFixedCurrent() instead of using SetLimits().

Using sequences of pulses

Consider the following sequence of output pulses:

When using the original firmware, a pause of MinOffTime is required after each pulse. The timing parameters have to be adjusted as follows:

MaxOnTime: 1 ms
MinOffTime: 1 ms

This results in a duty cycle of 0.5. The calculated power losses do not account for the longer pause time for each period.

With newer firmware versions it is possible to add up both parameters across multiple pulses. In the example above, we can use the sum for one time period between position 2 ms and 10 ms:

MaxOnTime: 2 ms
MinOffTime: 6 ms

The resulting duty cycle is now 0.25, which allows the use of higher output currents under the same conditions. The user could also decide to add up the values for multiple periods. But please note that higher absolute time values will also reduce the maximum output current.

Note: This feature requires firmware version ≥ 1.0.0.22.

Public Types
enum	STROBE_MODE
	Mode definitions for the strobe unit, used by SetTriggerMode() More...

enum	STROBE_OUTPUT_TYPE
	Type definitions for setting the output channel of the Strobe unit, used by SetOutputType() More...

enum	STROBE_SOURCE
	Trigger source definitions for the strobe unit, used by SetTriggerSource() More...

Public Member Functions
bool	Calibrate (char LogText[20 *1024])
	Calibrates the strobe unit More...

bool	GetCurrent (int &Current)
	Gets the current value of the strobe output. More...

bool	GetLimits (unsigned int &MaxOnTime, unsigned int &MinOffTime, unsigned int &MaxCurrent)
	Returns the power related limits currently used. More...

bool	GetOnTime (int &OnTime)
	Returns the ON-time of the strobe output. More...

bool	GetOutputType (STROBE_OUTPUT_TYPE &OutputType)
	Return the OutputType of the Strobe unit. More...

bool	GetTemp (unsigned short &Temp)
	Reads temperature of the FlashBox Strobe unit. More...

bool	GetTriggerDelay (int &TriggerDelay)
	Returns the trigger delay. More...

bool	GetTriggerMode (int &TriggerMode)
	Returns the trigger mode. More...

bool	GetTriggerSource (STROBE_SOURCE &TriggerSource, int &InvertTrigger)
	Returns the trigger source. More...

bool	GetVoltage (int &Voltage)
	Returns the voltage value of the strobe output. More...

bool	Init (bool ResetParameter=true)
	Initializes the Strobe unit. More...

bool	SetCurrent (int Current, int Validate=0)
	Sets the current value of the strobe output. More...

bool	SetFixedCurrent (int SupplyVoltage, int LoadVoltage, unsigned int MaxOnTime, unsigned int MinOffTime, unsigned int Current, int &Result)
	Sets a fixed operating point for the strobe output. More...

bool	SetLimits (int LimitCurrent, int MaxSupplyVoltage, int MaxLoadVoltage, unsigned int MaxOnTime, unsigned int MinOffTime, unsigned int MaxCurrent, int &Result)
	Calculates the minimum permitted OFF-time or the maximum permitted current. More...

bool	SetOnTime (unsigned int OnTime)
	Sets the ON-time of the strobe output for edge triggered modes. More...

bool	SetOutputType (STROBE_OUTPUT_TYPE OutputType)
	Selects the output channel for the Strobe unit. More...

bool	SetTriggerDelay (unsigned int TriggerDelay)
	Sets the trigger delay. More...

bool	SetTriggerMode (STROBE_MODE TriggerMode, int &Result)
	Sets the trigger mode. More...

bool	SetTriggerSource (STROBE_SOURCE TriggerSource, int InvertTrigger)
	Sets the trigger source for hardware triggered modes. More...

	Strobe ()
	Default constructor for the device object More...

bool	SwTrigger (int Value)
	Sets the trigger signal for software triggered and manual mode. More...

Public Member Functions inherited from VIB::iDevice
bool	Close ()
	Closes a device More...

	iDevice (const iDevice &device)
	The copy constructor makes a copy of the existing device object More...

bool	isOpen (bool &state)
	Returns the open state of a device object More...

bool	Open (unsigned int Index=0)
	Opens a device More...

iDevice &	operator= (const iDevice &device)
	The assignment operator makes a copy of the existing device object More...

virtual	~iDevice ()
	Deletes the device object More...

Member Enumeration Documentation

◆ STROBE_MODE

enum VIB::Strobe::STROBE_MODE

Mode definitions for the strobe unit, used by SetTriggerMode()

Enumerator
STROBE_MODE_SOFTWARE_EDGE	Software triggered.
STROBE_MODE_SOFTWARE_COPY	Manual ON/OFF by Software.
STROBE_MODE_HARDWARE_EDGE	Hardware triggered by edge.
STROBE_MODE_HARDWARE_COPY	Hardware triggered by level.

◆ STROBE_OUTPUT_TYPE

enum VIB::Strobe::STROBE_OUTPUT_TYPE

Type definitions for setting the output channel of the Strobe unit, used by SetOutputType()

Enumerator
STROBE_OUTPUT_TYPE_OFF	The LED voltage is disconnected.
STROBE_OUTPUT_TYPE_DEFAULT	Sets the default value.
STROBE_OUTPUT_TYPE_EXTERNAL	External connectors are used (default)
STROBE_OUTPUT_TYPE_INTERNAL	The internal ring light is used (only valid for the VisionCam XM)

◆ STROBE_SOURCE

enum VIB::Strobe::STROBE_SOURCE

Trigger source definitions for the strobe unit, used by SetTriggerSource()

Note: The VisionBox AGE-X1 doesn't have a Multiplexer and therefore uses different source signals than new hardware generations.

Enumerator
STROBE_SOURCE_MUX_OUT0	Multiplexer Output 0.
STROBE_SOURCE_MUX_OUT1	Multiplexer Output 1.
STROBE_SOURCE_MUX_OUT2	Multiplexer Output 2.
STROBE_SOURCE_MUX_OUT3	Multiplexer Output 3.
STROBE_SOURCE_MUX_OUT4	Multiplexer Output 4.
STROBE_SOURCE_MUX_OUT5	Multiplexer Output 5.
STROBE_SOURCE_MUX_OUT6	Multiplexer Output 6.
STROBE_SOURCE_MUX_OUT7	Multiplexer Output 7.
STROBE_SOURCE_MUX_OUT8	Multiplexer Output 8.
STROBE_SOURCE_MUX_OUT9	Multiplexer Output 9.
STROBE_SOURCE_MUX_OUT10	Multiplexer Output 10.
STROBE_SOURCE_MUX_OUT11	Multiplexer Output 11.
STROBE_SOURCE_MUX_OUT12	Multiplexer Output 12.
STROBE_SOURCE_MUX_OUT13	Multiplexer Output 13.
STROBE_SOURCE_MUX_OUT14	Multiplexer Output 14.
STROBE_SOURCE_MUX_OUT15	Multiplexer Output 15.
STROBE_SOURCE_MUX_OUT16	Multiplexer Output 16.
STROBE_SOURCE_MUX_OUT17	Multiplexer Output 17.
STROBE_SOURCE_MUX_OUT18	Multiplexer Output 18.
STROBE_SOURCE_MUX_OUT19	Multiplexer Output 19.
STROBE_SOURCE_MUX_OUT20	Multiplexer Output 20.
STROBE_SOURCE_MUX_OUT21	Multiplexer Output 21.
STROBE_SOURCE_MUX_OUT22	Multiplexer Output 22.
STROBE_SOURCE_MUX_OUT23	Multiplexer Output 23.
STROBE_SOURCE_DIG_IN0	Digital input 0 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN1	Digital input 1 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN2	Digital input 2 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN3	Digital input 3 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN4	Digital input 4 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN5	Digital input 5 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN6	Digital input 6 (VisionBox AGE-X1 only)
STROBE_SOURCE_DIG_IN7	Digital input 7 (VisionBox AGE-X1 only)
STROBE_SOURCE_RS422_IN0	RS422 input 0 (VisionBox AGE-X1 only)
STROBE_SOURCE_RS422_IN1	RS422 input 1 (VisionBox AGE-X1 only)
STROBE_SOURCE_RS422_IN2	RS422 input 2 (VisionBox AGE-X1 only)
STROBE_SOURCE_TRIGGEN_OUT0	Trigger Generator output 0 (VisionBox AGE-X1 only)
STROBE_SOURCE_TRIGGEN_OUT1	Trigger Generator output 1 (VisionBox AGE-X1 only)
STROBE_SOURCE_TRIGGEN_OUT2	Trigger Generator output 2 (VisionBox AGE-X1 only)
STROBE_SOURCE_TRIGGEN_OUT3	Trigger Generator output 3 (VisionBox AGE-X1 only)

Constructor & Destructor Documentation

◆ Strobe()

VIB::Strobe::Strobe ( )

Default constructor for the device object

The device must be opened with Open() before it can be used.

Member Function Documentation

◆ Calibrate()

bool VIB::Strobe::Calibrate ( char LogText[20 *1024] )

Calibrates the strobe unit

Calibration of the strobe unit is normally not required because the hardware is delivered calibrated.

Connect a zero Ohm bridge between the LED+ and LED- terminals before calling this function.
After success, the calibration values are stored permanently.

Returns: Text containing the calibration result data

Parameters

LogText Text containing the calibration result data

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetCurrent()

bool VIB::Strobe::GetCurrent ( int & Current )

Gets the current value of the strobe output.

Parameters

Current ≥ 0: Current in mA
< 0: Error

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetLimits()

bool VIB::Strobe::GetLimits	(	unsigned int &	MaxOnTime,
		unsigned int &	MinOffTime,
		unsigned int &	MaxCurrent
	)

Returns the power related limits currently used.

Parameters

MaxOnTime	Maximum allowed ON-time (µs)
MinOffTime	Minimum allowed OFF-time (µs)
MaxCurrent	Maximum allowed current (mA)

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetOnTime()

bool VIB::Strobe::GetOnTime ( int & OnTime )

Returns the ON-time of the strobe output.

Parameters

OnTime > 0: ON-time in µs
< 0: Error

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetOutputType()

bool VIB::Strobe::GetOutputType ( STROBE_OUTPUT_TYPE & OutputType )

Return the OutputType of the Strobe unit.

Parameters

OutputType The current used sink type

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetTemp()

bool VIB::Strobe::GetTemp ( unsigned short & Temp )

Reads temperature of the FlashBox Strobe unit.

Parameters

Temp	Temperature in °C

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetTriggerDelay()

bool VIB::Strobe::GetTriggerDelay ( int & TriggerDelay )

Returns the trigger delay.

Parameters

TriggerDelay ≥ 0: Trigger delay in µs
< 0: Error

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetTriggerMode()

bool VIB::Strobe::GetTriggerMode ( int & TriggerMode )

Returns the trigger mode.

Parameters

TriggerMode ≥ 0: Trigger mode (see STROBE_MODE)
< 0: Error

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetTriggerSource()

bool VIB::Strobe::GetTriggerSource	(	STROBE_SOURCE &	TriggerSource,
		int &	InvertTrigger
	)

Returns the trigger source.

Parameters

TriggerSource	Trigger source
InvertTrigger	Polarity of the trigger signal

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ GetVoltage()

bool VIB::Strobe::GetVoltage ( int & Voltage )

Returns the voltage value of the strobe output.

Parameters

Voltage ≥ 0: Voltage in mV
< 0: Error

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ Init()

bool VIB::Strobe::Init ( bool ResetParameter = true )

Initializes the Strobe unit.

Parameters

ResetParameter The parameter is ignored, the strobe unit is always reset to default settings

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetCurrent()

bool VIB::Strobe::SetCurrent	(	int	Current,
		int	Validate = `0`
	)

Sets the current value of the strobe output.

If the Validate parameter is set to 0, the characteristics value of the analog strobe circuit stored within an EEPROM is used without validation.
The Validate parameter can be set to 1 in order to measure and adjust the current. The deviation of the desired current can be minimized in this mode. If the deviation is too high, this function will return with an error. The strobe output is activated multiple times for 200 µs at the given current when calling this function. Please note that the Max. ON-time parameter must be 200 µs or more in this mode.

Parameters

Current	Desired current in mA
Validate	0: Don't validate current 1: Validate current

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetFixedCurrent()

bool VIB::Strobe::SetFixedCurrent	(	int	SupplyVoltage,
		int	LoadVoltage,
		unsigned int	MaxOnTime,
		unsigned int	MinOffTime,
		unsigned int	Current,
		int &	Result
	)

Sets a fixed operating point for the strobe output.

This function can be used as an alternative to SetLimits() and SetCurrent(). It allows for higher output power, if the difference between SupplyVoltage and LoadVoltage is small.

The output current will be set to the specified value and this function returns the calculated minimum OFF-time. The current can't be changed with SetCurrent() after calling this function. But SetCurrent() can still be used with the same current value in order to validate the actual current.

Background: SetLimits() assumes a resistive load characteristic, which can lead to higher internal power losses at lower currents. Because the current can be decreased by the user, SetLimits() will calculate the limits based on the worst-case current.

Parameters

SupplyVoltage

Supply voltage used for the strobe output:

Value	Effect
12...30	The actual power supply voltage used.

LoadVoltage The voltage across the load when the output current is equal to Current

MaxOnTime Maximum allowed ON-time in µs (max. ~ 4s)

MinOffTime Minimum allowed OFF-time in µs (max. ~ 4s, use 0 to allow steady ON state)

Current Output current in mA

Result ≥ 0: Minimum allowed OFF-time (µs)
< 0: Error

Warning: In the case of wrong parameters the hardware can be damaged!

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

Note: This function was introduced with library version 1.5.2.0.

◆ SetLimits()

bool VIB::Strobe::SetLimits	(	int	LimitCurrent,
		int	SupplyVoltage,
		int	LoadVoltage,
		unsigned int	MaxOnTime,
		unsigned int	MinOffTime,
		unsigned int	Current,
		int &	Result
	)

Calculates the minimum permitted OFF-time or the maximum permitted current.

The operating parameters for the strobe output can be limited by the strobe unit or by the lighting hardware connected to the output. This function is be used to calculate and limit these parameters.

The MaxOnTime, MinOffTime and Current parameters should first be chosen by the user in a way, that the limits of the lighting unit are not exceeded.
Based on these parameters, this function ensures that the limits of the strobe unit are not exceeded. The parameter LimitCurrent controls whether the minimum OFF-time or the maximum current will be reduced.

If the strobe active time exceeds the maximum ON-time, the output will be turned off by the FPGA, until the inactive time reaches the minimum OFF-time.

Parameters

LimitCurrent 0: Calculate the minimum allowed OFF-time
1: Calculate the maximum allowed current

SupplyVoltage

Supply voltage used for the strobe output:

Value	Effect
12...30	The actual power supply voltage used.
-1	The worst case supply voltage is assumed to calculate the limits (30 V).

LoadVoltage The load voltage when the output current is equal to Current (set to -1 to use worst-case value)

MaxOnTime Maximum allowed ON-time in µs (max. ~ 4 s; set MinOffTime to 0 to allow steady ON state)

MinOffTime Minimum allowed OFF-time in µs (max. ~ 4 s)

Current Maximum allowed output current in mA

Result LimitCurrent = 0: New minimum allowed OFF-time (µs)
LimitCurrent = 1: New maximum allowed current (mA)

Warning: In the case of wrong parameters the hardware can be damaged!

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetOnTime()

bool VIB::Strobe::SetOnTime ( unsigned int OnTime )

Sets the ON-time of the strobe output for edge triggered modes.

Parameters

OnTime On time in µs

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetOutputType()

bool VIB::Strobe::SetOutputType ( STROBE_OUTPUT_TYPE OutputType )

Selects the output channel for the Strobe unit.

This function is primarily used by the VisionCam XM which can provide the LED current to the supply and I/O connector, or to the internal ring light (default).

Parameters

OutputType The desired channel

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetTriggerDelay()

bool VIB::Strobe::SetTriggerDelay ( unsigned int TriggerDelay )

Sets the trigger delay.

The trigger delay is only used in software triggered and edged triggered hardware mode.

Parameters

TriggerDelay Delay in µs (max. ~4s)

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetTriggerMode()

bool VIB::Strobe::SetTriggerMode	(	STROBE_MODE	TriggerMode,
		int &	Result
	)

Sets the trigger mode.

The strobe output can be triggered using four different modes:

Software triggered (STROBE_MODE_SOFTWARE_EDGE):
The strobe output is activated by calling SwTrigger(1). The output will be reset after the ON-time has expired.
Manual Software (STROBE_MODE_SOFTWARE_COPY):
The strobe output is set to ON/OFF by calling SwTrigger(1) / SwTrigger(0). If the minimum OFF-time is greater than 0, the mode will be set to software triggered instead.
Hardware by edge (STROBE_MODE_HARDWARE_EDGE):
The strobe output is activated on rising (non-inverted) or falling (inverted) edge of the selected trigger signal. Polarity can be changed with SetTriggerSource(). The strobe output will be reset after the ON-time has expired.
Hardware by level (STROBE_MODE_HARDWARE_COPY):
The strobe output is activated by the level of the external trigger input. If the minimum OFF-time is greater than 0, the trigger mode will be set to hardware by edge instead.

Parameters

TriggerMode	Desired trigger mode
Result	≥ 0: New trigger mode < 0: Error

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SetTriggerSource()

bool VIB::Strobe::SetTriggerSource	(	STROBE_SOURCE	TriggerSource,
		int	InvertTrigger
	)

Sets the trigger source for hardware triggered modes.

Hardware triggered mode must be selected first with SetTriggerMode().

Parameters

TriggerSource	Select the signal used as trigger source
InvertTrigger	Polarity of the trigger signal

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

◆ SwTrigger()

bool VIB::Strobe::SwTrigger ( int Value )

Sets the trigger signal for software triggered and manual mode.

Parameters

Value 1: Activates the strobe output
0: Deactivates the strobe output (only used in level/copy mode)

Returns: true for success, use VIBSystem::GetLastErrorString() for an error description

Detailed Description

Operating conditions

Maximizing output power

Using sequences of pulses

Public Types

Public Member Functions

Member Enumeration Documentation

◆ STROBE_MODE

◆ STROBE_OUTPUT_TYPE

◆ STROBE_SOURCE

Constructor & Destructor Documentation

◆ Strobe()

Member Function Documentation

◆ Calibrate()

◆ GetCurrent()

◆ GetLimits()

◆ GetOnTime()

◆ GetOutputType()

◆ GetTemp()

◆ GetTriggerDelay()

◆ GetTriggerMode()

◆ GetTriggerSource()

◆ GetVoltage()

◆ Init()

◆ SetCurrent()

◆ SetFixedCurrent()

◆ SetLimits()

◆ SetOnTime()

◆ SetOutputType()

◆ SetTriggerDelay()

◆ SetTriggerMode()

◆ SetTriggerSource()

◆ SwTrigger()