IOF_LB_ParityCheck

IOF_LB_ParityCheck 1:

The IOF_LB_ParityCheck function block reads the parity error counters of the Beckhoff Lightbus modules (e.g. BK2000). In contrast to the IOF_LB_ParityCheckWithReset function block, the counter values are not reset. The master maintains an 8-bit error counter for each module. These counters work without overflow. A maximum of 256 bytes of data, and therefore 256 counters, can be read. The number of error counters to be read is specified by the input variables: LEN and DESTADDR. If, for instance, there are only 5 modules in the ring, then the DESTADDR parameter can be supplied with the address of a data buffer of 5 bytes, and the LEN parameter can be supplied with the value 5.

Inputs

VAR_INPUT
    NETID     : T_AmsNetId;
    DEVICEID  : UDINT;
    LEN       : UDINT;
    DESTADDR  : PVOID;
    START     : BOOL;
    TMOUT     : TIME := DEFAULT_ADS_TIMEOUT;
END_VAR

Name	Type	Description
NETID	T_AmsNetId	The network address of the TwinCAT computer on which the ADS command is to be executed can be specified here. For the local computer an empty string may be specified.
DEVICEID	UDINT	DeviceId specifies the I/O device on which the function is to be executed. The device IDs are specified by the TwinCAT system during the hardware configuration.
LEN	UINT	Length in bytes of the data to be read.
DESTADDR	PVOID	The address of the data buffer into which the parity data is to be written.
START	BOOL	The function block is enabled by a positive edge at this input.
TMOUT	TIME	Specifies the time-out period that must not be exceeded when the command is executed.

Outputs

VAR_OUTPUT
    BUSY    : BOOL;
    ERR     : BOOL;
    ERRID   : UDINT;
END_VAR

Name	Type	Description
BUSY	BOOL	When the function block is enabled, this output is set and remains set until a feedback is received.
ERR	BOOL	If an error should occur during the transfer of the command, then this output is set once the BUSY output was reset.
ERRID	UDINT	Returns the ADS error number when the ERR output is set.

Sample:

PROGRAM MAIN
VAR
    IOF_LB_ParityCheck1 : IOF_LB_ParityCheck;
    ParityData          : ARRAY[1..256] OF BYTE;
    StartParityCheck    : BOOL;
    ParityCheck_Busy    : BOOL;
    ParityCheck_Err     : BOOL;
    ParityCheck_ErrId   : UDINT;
END_VAR

Requirements

Development environment	Target platform	IO hardware	PLC libraries to be integrated (category group)
TwinCAT v3.1.0	None. This functionality is not supported by TwinCAT 3 at present!	Beckhoff Lightbus Master: C1220 ISA; FC200x PCI	Tc2_IoFunctions (IO)