How to Read the max/min position error record

20200325 by advan

Description

TwinCAT NC provide max/min position error value . The record will start after axis controller enable , Reset record after axes reset(MC_Reset)

ADS Address

Port 501

Index Group = 0x4100 + AxisID

Index Offset = 0x00n0 0000 , n: element index start from 0

Len

TC2 (112 byte)

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TC3 (256 byte)

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TC2 "Index offset" specification for axis state (Index group 0x4100 + ID)

Index offset (Hex)	Access	Axis type	Data type	Phys. unit	Definition range	Description	Note
0x00n00000 n = Axis element index like second encoder , drive , control First element n = 0 Second element n = 1	Read	every (online structure for axis data)	{			AXIS ONLINE STRUCTURE (NC/CNC)	Cannot be traced by oscilloscope! (NCAXISSTATE_ ONLINESTRUCT)
			INT32	1		Error state
			REAL64	e.g. mm		Actual position
			REAL64	e.g. degree		Modulo actual position
			REAL64	e.g. mm		Set position
			REAL64	e.g. degree		Modulo set position
			REAL64	e.g. mm/s		Optional: actual velocity
			REAL64	e.g. mm/s		Set velocity
			UINT32	%	0...1000000	Speed override (1000000 == 100%)
			REAL64	e.g. mm		Following error position
			REAL64	e.g. mm		PeakHold value for max. negative following error (pos.)
			REAL64	e.g. mm		PeakHold value for max. positive following error (pos.)
			REAL64	%		Controller output in percent
			REAL64	%		Total output in percent
			UINT32	1	≥ 0	Axis-Status-DWord
			UINT32	1	≥ 0	Axis-Control-DWord
			UINT32	1	≥ 0	Slave coupling state (state)
			UINT32	1	0; 1,2,3...	Axis control loop index
			}			112 bytes

TC3 "Index offset" specification for Axis state (Index group 0x4100 + ID)

Index offset ( Hex )	Access	Axis type	Data type	Phys. unit	Definition range	Description	Note
0x00n00000 n = Axis element index like second encoder , drive , control First element n = 0 Second element n = 1	Read	every (online structure for axis data)	{			AXIS ONLINE STRUCTURE (NC/CNC)	Changed from TC3, not oscilloscopeable! (NCAXISSTATE_ONLINESTRUCT)
			INT32	1		Error state
			INT32			Reserved
			REAL64	e.g. mm		Actual position
			REAL64	e.g. degree		Modulo actual position
			REAL64	e.g. mm		Set position
			REAL64	e.g. degree		Modulo set position
			REAL64	e.g. mm/s		Optional: actual velocity
			REAL64	e.g. mm/s		Set velocity
			UINT32	%	0...1000000	speed override (1000000 == 100%)
			UINT32			Reserved
			REAL64	e.g. mm		Following error position
			REAL64	e.g. mm		PeakHold value for max. neg. position lag (pos.)
			REAL64	e.g. mm		Peak hold value for max. pos. following error. (pos.)
			REAL64	%		Controller output in percent
			REAL64	%		Total output in percent
			UINT32	1	≥ 0	Axis status double word
			UINT32	1	≥ 0	Axis control double word
			UINT32	1	≥ 0	Slave coupling state (state)
			UINT32	1	0; 1,2,3...	Axis control loop index
			REAL64	e.g. mm/s^2		Actual acceleration
			REAL64	e.g. mm/s^2		Set acceleration
			REAL64	e.g. mm/s^3		Set jerk (new from TC3.1 B4013)
			REAL64	e.g. 100% = 1000		Set torque or set force (reserved, not implemented)
			REAL64	e.g. 100% = 1000		Actual torque or actual force (new from TC3.1 B4013)
			}			256 byte

PLC Sample Code (TC3)

Define a struct same as memory layout & fulfill data size 256 bytes & define pack mode continuously(TC3)

{attribute 'pack_mode' := '1'}

TYPE TC3_NCAXISSTATE_ONLINESTRUCT :

STRUCT

Error_State : DWORD;

Dummy_0004 : DWORD;

Actual_Position : LREAL;

Modulo_Actual_Position : LREAL;

Set_Position : LREAL;

Modulo_Set_Position : LREAL;

Actual_Velocity : LREAL;

Set_Velocity : LREAL;

Speed_Override : UDINT; (* 1000000 == 100% *)

Dummy_0052 : DWORD;

Position_Lag : LREAL;

PeakHold_Max_Neg_Position_Lag : LREAL;

PeakHold_Max_Pos_Position_Lag : LREAL;

Controller_Output_In_Percent : LREAL;

Total_Output_In_Percent : LREAL;

Axis_Status_Dword : DWORD;

Axis_Control_Dword : DWORD;

Slave_Coupling_State : DWORD;

Axis_Control_Loop_Index : DINT;

Actual_Acceleration : LREAL;

Set_Acceleration : LREAL;

Set_Jerk : LREAL;

Set_Torque : LREAL; (* or force *)

Actual_Torque : LREAL; (* or force *)

Dummy_0160 : ARRAY[0..95] OF BYTE;

END_STRUCT

END_TYPE

PROGRAM MAIN

VAR

stTC3AxisData : TC3_NCAXISSTATE_ONLINESTRUCT;

FB_AdsRead : ADSREAD;

END_VAR

FB_AdsRead(NETID:= , (* Assign target *)

PORT:= 501,

IDXGRP:= 16#4101, (* 16#4100 + Axis ID *)

IDXOFFS:= , (* most case = 0 *)

LEN:= SIZEOF(stTC3AxisData),

DESTADDR:= ADR(stTC3AxisData),

READ:= ,

TMOUT:= ,

BUSY=> ,

ERR=> ,

ERRID=> );

PLC Sample Code (TC2)