DriveParamRead

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Function Block A function block groups an algorithm and a set of private data. It has inputs and outputs. - Reads a drive parameter by sending an ASCII command to a drive.

Inputs

Input	Data Type	Range	Unit	Default	Description
Execute	BOOL	0, 1	N/A	No default	On the rising edge A rising edge is the transition of a digital signal from low to high. It is also called positive edge of Execute, a drive parameter is read. The function block processes only one request at a time. If Execute is toggled quickly so that another rising edge occurs before the function block has completed, the function block does not issue a second read command.
Drive	INT	No range	N/A	No default	The address of the drive where data is read. The first node usually has the value 1001. The second node usually has the value 1002. Alternately, use the members of the EtherCAT ***EtherCAT is an open, high-performance Ethernet-based fieldbus system. The development goal of EtherCAT was to apply Ethernet to automation applications which require short data update times (also called cycle times) with low communication jitter (for synchronization purposes) and low hardware costs structure to specify a drive's address to Create Variables.
Param	STRING	No range	N/A	No default	The parameter to read.

Input

Data Type

Range

Unit

Default

Description

Execute

BOOL

0, 1

N/A

No default

On the rising edge A rising edge is the transition of a digital signal from low to high. It is also called positive edge of Execute, a drive parameter is read.

The function block processes only one request at a time.
If Execute is toggled quickly so that another rising edge occurs before the function block has completed, the function block does not issue a second read command.

Drive

INT

No range

N/A

No default

The address of the drive where data is read.

The first node usually has the value 1001.
The second node usually has the value 1002.

Alternately, use the members of the EtherCAT ***EtherCAT is an open, high-performance Ethernet-based fieldbus system. The development goal of EtherCAT was to apply Ethernet to automation applications which require short data update times (also called cycle times) with low communication jitter (for synchronization purposes) and low hardware costs structure to specify a drive's address to Create Variables.

Param

STRING

No range

N/A

No default

The parameter to read.

Outputs

Output	Data Type	Range	Unit	Description
Done	BOOL	No range	N/A	Indicates whether this function block has completed without error.
Error	BOOL	No range	N/A	Indicates whether this function block call has completed with error.
ErrorID	DINT	No range	N/A	The DriveParamRead error result if Error is TRUE. Upon success, Error is set to 0 (zero). See the EtherCAT Error Codes for more information.
Value	LREAL	No range	N/A	The value of the drive parameter. Value is only set when the function block has successfully completed.
Units	STRING	No range	N/A	The value of the drive parameter. Value is only set when the function block has successfully completed.

Remarks

Use this function block to read drive parameters that are not supported by other function blocks.

Examples include:

Motor temperature

Drive bus voltage

Present drive limit settings

Present regeneration loading

Drive display

Fault history

It takes multiple cycles to complete this function block.
Typically only one DriveParamRead or DriveParamWrite function should be active for each axis at one time.
If executing this function block continuously or if multiple times is required, add code that waits for this function block to complete (Done bit = 1) before executing it again.
- See stats about the Execution Time.
See EtherCAT Function Blocks That Work With Drive Parameters for information about function blocks that are not supported by ML and MC function blocks.

Figure 7-187: DriveParamRead

This function block uses and reserves the EtherCAT SDO Channel.
The SDO Channel remains reserved until the done output is TRUE.
This FB should be called at each cycle until the done output is TRUE.
If it is not called at each cycle, the rest of SDO communication (e.g., the AKD GUI "Graphical User Interface" A GUI is a type of user interface which allows people to interact with a computer and computer-controlled devices Views) is blocked.
Using this FB in SFC "Sequential function chart" It can be used to program processes that can be split into steps. The main components of SFC are: - Steps with associated actions - Transitions with associated logic conditions - Directed links between steps and transitions P0 or P1 steps is not recommended because these steps are executed only once.
If this FB is used in P0 or P1, then it must be used in an SFC N step to ensure the FB completes.

EtherCAT Error Codes

List of EtherCAT Error Codes
Error Code	Value dec (hex)	Description
ECERR_OK	0	The SDO call succeeded
ECERR_DEVICE_ERROR	1792 (0x700)	EtherCAT device is not accessible
ECERR_DEVICE_INVALIDCMD	1794 (0x702)	Invalid mailbox command
ECERR_DEVICE_INVALIDINDEX	1795 (0x703)	An invalid value for the Index input was specified
ECERR_DEVICE_INVALIDACCESS	1796 (0x704)	Reading of the variable is not permitted
ECERR_DEVICE_INVALIDSIZE	1797 (0x705)	An invalid size for the parameter was specified
ECERR_DEVICE_INVALIDDATA	1798 (0x706)	Invalid parameter value(s) in SDO index and/or sub-index
ECERR_DEVICE_NOTREADY	1799 (0x707)	Device is not in a ready state, network is not in operational
ECERR_DEVICE_BUSY	1800 (0x708)	Device is not available to respond
ECERR_DEVICE_INVALIDCONTEXT	1801 (0x709)	Device responded with an illegal error code, indicating the command is not allowed under the present conditions
ECERR_DEVICE_NOMEMORY	1802 (0x70A)	EtherCAT mailbox is out of memory or device is out of disk space
ECERR_DEVICE_INVALIDPARM	1803 (0x70B)	EtherCAT mailbox request was not valid
ECERR_DEVICE_NOTFOUND	1804 (0x70C)	EtherCAT device not found
ECERR_DEVICE_SYNTAX	1805 (0x70D)	An unexpected error occurred
ECERR_DEVICE_INVALIDSTATE	1810 (0x712)	The EtherCAT device is in an invalid state
ECERR_DEVICE_TIMEOUT	1817 (0x719)	The EtherCAT device failed to respond, timing out
ECERR_DEVICE_INSERTMAILBOX	1826 (0x722)	Error while inserting the mailbox command into internal FIFO
ECERR_DEVICE_INVALIDOFFSET	1827 (0x723)	An invalid value for the SubIndex input was specified
ECERR_DEVICE_UNKNOWNMAILBOXCMD	1828 (0x724)	The master sent an unknown mailbox command to the slave
ECERR_DEVICE_ACCESSDENIED	1829 (0x725)	Device responded with an invalid access error code, indicating the command is not allowed
ECERR_DEVICE_INVALIDADDR	1832 (0x728)	Can’t send a mailbox command to the specified slave
ECERR_DEVICE_NOT_A_FSOE_MASTER	1836 (0x72c)	Device is not a FSoE master.
ECERR_DEVICE_PARAM_ACCESS_ERROR	1920 (0x780)	Unknown error occurred while accessing parameter
ECERR_DEVICE_PARAM_NOT_FOUND	1921 (0x781)	Parameter was not found
ECERR_DEVICE_PARAM_NOT_INTEGER	1922 (0x782)	Parameter is a floating-point value. Integer value required.
ECERR_DEVICE_VALUE_IS_NEGATIVE	1923 (0x783)	No negative values allowed. Value specified was negative.
ECERR_DEVICE_VALUE_OUT_OF_RANGE	1924 (0x784)	Value is out of data-range
ECERR_DEVICE_VALUE_GREATER_THAN_MAX	1925 (0x785)	Value bigger than maximum
ECERR_DEVICE_VALUE_LOWER_THAN_MIN	1926 (0x786)	Value lower than minimum
ECERR_CLIENT_ERROR	2048 (0x800)	Error in Mailbox response to a previously sent mailbox command
ECERR_CLIENT_TIMEOUT	2049 (0x801)	The SDO command timed out
ECERR_CLIENT_ INVALIDPARM	2050 (0x802)	An invalid value was specified
ECERR_CLIENT_ INVALIDSIZE	2051 (0x803)	An invalid value for the size input was specified

FBD Language

FFLD Language

IL Language

Not available.

ST Language

(* Read PL.KP on first AKD Drive on EtherCAT network *)
      
(* The code continually calls the FB (without re-executing it) until the first execution is done, then reads the returned value from the drive and reset the FB *)
      
IF ReadPropGain then
   Inst_DriveParamRead1( 1, 1001, 'PL.KP' );
End_If;

On Inst_DriveParamRead1.Done do
   Inst_DriveParamRead1( 0, 1001, 'PL.KP' );
   PositionProportionalGain := Inst_DriveParamRead1.Value; (* Reads the returned value from the drive *)
   ReadPropGain := 0; (* Reset the FB *)
End_DO;