FB_VN_ReadRegister_REAL

FB_VN_ReadRegister_REAL 1:

This FB reads a REAL register from the camera. Requires an open control channel (e.g. by calling FB_VN_GevCameraControl.OpenCamera() before)

Syntax

Definition:

FUNCTION_BLOCK FB_VN_ReadRegister_REAL
VAR_INPUT
    nAddress                 : GVCP_REGISTER_ADDRESS;
    nEndian                  : UINT;
    bRead                    : BOOL;
    nTimeout                 : TIME;
END_VAR
VAR_OUTPUT
    fValue                   : REAL;
    bBusy                    : BOOL;
    bError                   : BOOL;
    nErrorId                 : UDINT;
END_VAR
VAR
    oidITcVnGevImageProvider : OTCID;
END_VAR

FB_VN_ReadRegister_REAL 2: Inputs

Name

Type

Default

Description

nAddress

GVCP_REGISTER_ADDRESS

 

The address of the register that should be read

nEndian

UINT

 

OPTIONAL: The endianness of the register. 0 = Big, 1 = Little. Default: 0

bRead

BOOL

 

Reading the register is triggered by a rising edge at this input.

nTimeout

TIME

VISION_ADS_TIMEOUT

Indicates the time before the function is cancelled.

FB_VN_ReadRegister_REAL 3: Outputs

Name

Type

Description

fValue

REAL

The read value

bBusy

BOOL

This output remains TRUE until the function block has executed a command, but at the longest for the duration supplied to the 'nTimeout' input. While bBusy = TRUE, no new command will be accepted at the inputs.

bError

BOOL

This output is switched to TRUE as soon as an error occurs during the execution of a command. The command-specific error code is contained in ‘nErrorId’. If the function block has a timeout error, 'bError' is TRUE and 'nErrorId' is 1861 (hexadecimal 0x745). Is reset to FALSE by the execution of a command at the inputs.

nErrorId

UDINT

Contains the ADS error code or the command-specific error code of the last executed command. Is reset to 0 by the execution of a command at the inputs.

Further information

FB_VN_ReadRegister_REAL 4:

Open camera Control Channel needed!

The Control Channel of the GigE Vision camera must be open in order to be able to use this function block. In addition, some camera parameters can only be changed if the image acquisition is stopped. It is therefore recommended to place the camera in the state TCVN_CS_OPENED first.

Parameter

nAddress

The register address identifies the camera register to be addressed. It is of the type GVCP_REGISTER_ADDRESS, which is an alias of the type UDINT. Thus, all register addresses have a size of 4 bytes. The register address of a camera parameter can be seen at the respective point in the configuration tree of the GigE Vision camera instance:

FB_VN_ReadRegister_REAL 5:

nEndian

Endianess describes the order in which the bytes of a camera register are arranged. This does not need to be considered any further in terms of the application and can be adopted as a property of the respective parameter of the configuration tree of the GigE Vision camera instance:

FB_VN_ReadRegister_REAL 6:

A Big Endian is represented by nEndian := 0 and a Small Endian by nEndian := 1. Big Endian is the default.

Samples

Required License

TC3 Vision Base

System Requirements

Development environment

Target platform

PLC libraries to include

TwinCAT V3.1.4024.54 or later

PC or CX (x64) with PL50, e.g. Intel 4-core Atom CPU

Tc3_Vision