Simulate quadrature encoder output without hardware

I am brand new to Labview and have not had any training other than youtube and this fine forum. I am a mechanic trying to solve a problem using labview. I am posting this new question because I don’t have any hardware so I can’t use the examples I’ve seen others pointing to.
I’m trying to simulate the output of a quadrature rotary encoder. Once I have done that I want to use Labview to program an instrument that reads that signal and makes mathematical calculations to it but I need the signal first. The encoder will attach to a shaft that will rotate clockwise and then counterclockwise at a rate of about 122 times a minute. The total shaft rotation will be between 0 - 18 degrees. It is important to me to know the direction of the shaft. The quadrature encoder will send out 2 square waves with one wave behind the other. The way I’ve tried to do this is by using 2 Simulate Signal modules each sending out a square wave at 2 Hz. I’ve connected a single knob controller to the both frequency inputs of the signal modules to simulate the speed the shaft rotates back and forth. I’ve done the exact same thing to the amplitude input to simulate the degrees the shaft turns before changing directions. My problem is the changing directions. I can delay the phase, which is what I want to do, but I can’t do it in real time and I can’t do it in a single 180 degree step. What I would like is a switch to change the B channel from +90 to -90 when it is toggled. If I could then toggle the switch when the amplitude reaches 18 degrees or less I will have an encoder signal. Thanks for any help you can provide.
steve
Attachments:
Rotory Encoder.vi ‏59 KB

Steve,
From what I understand, you want to make a 180 degree phase shift every N intervals? I modified your code to do this. Let me know if that gets at what you are doing.
Cheers,
Chris LS
National Instruments
Applications Engineer
Visit ni.com/gettingstarted for step-by-step help in setting up your system.
Attachments:
Rotory EncoderEdit.vi ‏61 KB

Similar Messages

Quadrature encoder

Hi,
I'm trying to make an position measurment with a quadrature encoder.
My hardware is a6031E card, and I 'm using DAQmx 7.4.0.
I read the AN84. So I connected Channel A to Ctrl0_src (PFI8) and
Channel B to ctrl0_up-down (Port0.6). I used the
"quad_encoder_with_E-series_(STC)-daqmx.vi".
It first didn't work : il was counting up and not down or the opposite whether I was couting rising or falling edge.
Then it worked (I cannot see what I changed, I think I did not change anything but it's impossible).
And now, it doesn't work anymore. Even when I create a global channel
and test it in MAX, it counts up good, but when irotate the shaft the
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Can somebody telle me where I made a mistake and what I forgot.
Thanks.

Merci de me répondre.
J'avais bien configuré mon compteur en "controllé de manière externe" mais ça ne marchait pas.
J'ai trouvé la réponse ce matin : mon codeur disposait de sorties
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How to simulate a DAQ device and use it for testing applications without hardware???

how do i simulate a DAQ device
in MAX and use it for testing applications without hardware???
If my application requires inputs
from external hardware to proceed how can I simulate a DAQ device in LabVEIW?
i need to simulate several Digital inputs and Outputs to test the software. currently i dont have the hardware and DAQ device here.
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Kudos always welcome for helpful posts
Solved!
Go to Solution.

Hi,
There is no option to simulate traditional device.You need hardware for that so i would suggest to simulate a PXI device which has similar configuration to PCI-6014 and to do a small modification to your application..

2-Bit Quadrature Encoder without counters

I've noticed that the internal help in LabVIEW only mentioned Quadrature Encoders in terms of reading them with the counter inputs of a device that supports that type of reading. In case your DAQ does not support those counter inputs, such as the NI USB-6008, here is a LabVIEW VI that reads the output of a 2-bit encoder such as the Grayhill 61C22-01-04-02 optical encoder, and also reads its pushbutton output. Note that this would be called an "X4 decoding" in LabVIEW terms when referring to the decoding operation that it implements.
Datasheet: http://eceserv0.ece.wisc.edu/~morrow/ECE315/ARM7-FPGA/datasheets/grayhill_61C.pdf
Wire the encoder up with the load resistors listed in second page of the datasheet, and tie one of the pushbutton pins to 5V.
The VI labels the physical channels that you should wire up to. Example:
DAQmx Device Name: Dev1
Encoder 5V Supply Channel: /port0/line0
Note that I delete the device name from the channel selector, so "Dev1/port0/line0" becomes "/port0/line0". I only break the Device and channel names into 2 selectors because I swap DAQs often and I prefer to write my programs to just take a single "DAQmx Device" input that I can change in one place, then leave all the other lines the same. Just a little quirk of mine I guess.
The "X4 Quadrature Encoder (SubVI).vi" and its subVIs are the ones doing the work, the parent VI is just an example of how to use them.
I hope this helps somebody.
Ryan R.
R&D
Attachments:
Rotary Encoder Example.llb ‏100 KB

This was very helpful actually, thanks!

Can I use the 'Export Signal Property Node' on a quadrature encoder?

Hi,
So I don't know which counter board I'd be using yet for this (it's used in conjunction with a PCI-6280--the PCI-6280's counter inputs are all taken and so I need another board), but assuming this is possible at all in DAQmx I wouldn't mind knowing whether, say, the PCI-6601 (or any other timer board for that matter) could do this. I'm programming this in LabVIEW 2010 by the way.
I want to have a counter which counts the number of pulses on one channel (I'll call this the 'clock' channel) between when another channel goes from low to high (which I'll call the trigger). It's basically a pulse width measurement, but I only care if there are more than n clock pulses between triggers. I need to have a hardware-timed digital signal which goes from low to high if there are ever more than n pulses between trigger changing state from low to high.
What I am planning to do is this:
Wire 'trigger' to the z-input of the quadrature encoder, and set the z-input value to some arbitrary large value such that, at the quadrature encoder counter task's settings, the counter reaches terminal count in n pulses.
Configure the quadrature encoder counter using DAQmx Export Signal Property Node (tutorial I was looking at is here: http://zone.ni.com/devzone/cda/tut/p/id/5387 ) to toggle a digital channel ('counter event output') from low to high if the counter reaches terminal count (ie, if the encoder reads n pulses).
If the encoder ever reads n pulses on 'clock' between two rising pulses on 'trigger', it sets counter event output high.
Is this possible? Reading through the manual of M series PCI-62xx devices, the index pulse loads the counter with a particular value so it seems like you could conceivably set the counter to the terminal count if you wanted. My only real problem is whether DAQmx Export Signal Property Node works on all counter tasks or just on edge counting tasks.
Thanks in advance for your help. If this isn't possible, I can reply with more details on the problem this is supposed to solve so that you can help me figure out an alternate method.
Solved!
Go to Solution.

There is probably a way to do it, but it it may be easier to use an X-series board for the job. They support a new counter capability for count reset on a digital edge without needing to be configured in encoder position mode. I am not sure exactly how that feature's been implemented however, so maybe it won't make things easier after all.
The plan based on the hoped-for behavior:
1. Configure an X-series counter for pulse generation based on "ticks" of your clock channel.
2. Set both initial delay and low time to the critical # of ticks.
3. Configure for count reset on a digital edge (if possible in pulse generation mode)
4. Configure the count reset value to be the critical # (or possibly 1 less, if possible in pulse generation mode)
5. If you want the output to remain high indefinitely, configure the counter task to use its own output as a
pause trigger, and pause while high.
The way pulse generation works is to preload a # of "low time" ticks into the count register. Then every source edge will decrement the count. When the count reaches terminal count (0), the counter's output is toggled (or can be configured to pulse). The register is then loaded with the # of "high time" ticks and the process continues.
You would be perpetually interrupting the count-down process as long as you got your triggers in time. The count would keep getting reset to the # of low counts, keep decrementing toward 0 without reaching it, and so on. If ever you did reach 0, the output state would toggle high, then the high state would prevent subsequent clock signals from decrementing the count.
You can conceivably do a similar thing with a 6601, but I'm pretty sure you'd need 2 counters working together to get it working.
-Kevin P

How can I use flex motion control VI without hardware?

I would like to try and simulate the motion control of my system before i hook up the motion control card. But when I use the VI in flex motion contro took kit it asks for address or something and gives me an error. Can't I just simulate without hardware?

Hello,
The only way you can use FlexMotion without any hardware is to set it up as Open Loop Stepper Control. Otherwise, you will get errors when no encoder signal is fed back to the controller.
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How do you simulate an encoder using a virtual channel?

I am trying to use MAX to simulate hardware so I can create a program before I purchase the hardware. I will be purchasing a USB-6211, TTL quadrature encoder, and LVDT.
I want to simulate a quadrature encoder and a LVDT. I have created a virtual channel for each and a virtual USB-6211.
The LVDT is simulated by creating a virtual analog input channel. This virtual channel works when I test the vi.
The encoder is simulated by creating a virtual angle counter. This virtual channel does not work when I test the vi.
How do I get this virtual angle counter to work?

Kristen,
I do not get an error. The problem is that I do not get any action from the virtual channel.
For
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Simulation Problem.vi ‏124 KB

How to route Quadrature Encoder signal to CC1 using PCIe 1429 + IO extension card

Hi there,
i am currently trying to interface the Basler L304kc to the NI PCIe 1429 + Cameralink IO extension board
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Hi Alex,
I posted the following (similar) text to the support center but I think it is of common interest:
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There is also a SMB connector corresponding to the ext. channel 0.
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* imgSessionLineTrigSource2 -> what is this good for then? All your manuals are saying that this is done in MAX or the camera file by defining what signal drives the correspondung CC ine?? On the other side there is an example in CVI that does not work ("Trigger Each Line From Encoder") (at least it does not work with the PCIe1430).
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* imgSessionLineTrigSource2
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* imgSessionLineTrigSource2(iLS_ZK1_SessionID, IMG_SIGNAL_SCALED_ENCODER, 0, IMG_TRIG_POLAR_ACTIVEH, 0);
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* imgEncoderResetPosition(SessionID);
AND only in positive counting direction!
If I just run though the zero position without a position reset I do not get ExSync on CC1????
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F) now if in addition to E) i use
* imgSessionTriggerDrive2(iLS_ZK1_SessionID, IMG_SIGNAL_EXTERNAL, 0, IMG_TRIG_POLAR_ACTIVEH, IMG_TRIG_DRIVE_SCALED_ENCODER);
to drive ext. 0 (SMB connector) I can see exactly this behavior on the scope. No signal until I reset the encoder counter. Then I get signals as long as the image sequence is running. After the recording the signal disappears.
kind regards, Holger h.baur(at)ivisso.com

How to calibrate Quadrature Encoder signal

I have PCI-6601 and CB68-LP connector. How can I use these to interpret quadrature signals coming off an optical encoder (to sense the angular position of an-observatory dome). The encoder is 16-bit(don't know what this means in terms of PPR). I want to have a display in Labview that will show me the position of the dome in a fraction of 360 degrees with some reference(true north?), the dome rotation controlled by a three way switch(clockwise-off-anti-clockwise). I don't have much experience with labview and any help will be appreciated.

If the encoder is 16 bit then it would seem that: -
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1) Hardware interfacing.
2) Software read out.
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1.2 How are the signals conditioned for output to an external device.
The software is classic:
2.1 Input
2.2 Process
2.3 Output
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Good Luck

How do I use a quadrature encoder as an external clock (PCI 6229)

Hello, ( a similar post has been placed on DAQ forum apologies as I did not know best place)
I have a PCI 6229 M Series data acquisition card. I want to use a quadrature encoder to be the external clock driving the acquisition of a number of signals. I have set up reading 24 signals each time a clock pulse is received using the DAQ assistant and set my external clock to pin pfi8 (I think) this is then connected to an encoder output. This works well enough until the encoder is run too fast when it appears I am either missing pulses or getting bounce.
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Runtime Errors         OBJECTS_OBJREF_NOT_ASSIGNED_NO
Exception              CX_SY_REF_IS_INITIAL
Date and Time          09/09/2008 08:19:16
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Error in the ABAP Application Program
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Note down which actions and inputs caused the error.
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An exception occurred that is explained in detail below.
The exception, which is assigned to class 'CX_SY_REF_IS_INITIAL', was not
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after the short dump. Then choose "System->List->Save->Local File
(Unconverted)".
3. If the problem occurs in a problem of your own or a modified SAP
program: The source code of the program
In the editor, choose "Utilities->More
Utilities->Upload/Download->Download".
4. Details about the conditions under which the error occurred or which
actions and input led to the error.
The exception must either be prevented, caught within proedure
"HRXSS_PER_CLEANUP" "(FUNCTION)", or its possible occurrence must be declared
in the
RAISING clause of the procedure.
To prevent the exception, note the following:
System environment
SAP-Release 700
Application server... "ERPDEV01"
Network address...... "10.88.1.6"
Operating system..... "Windows NT"
Release.............. "5.2"
Hardware type........ "4x AMD64 Level"
Character length.... 16 Bits
Pointer length....... 64 Bits
Work process number.. 0
Shortdump setting.... "full"
Database server... "ERPDEV01"
Database type..... "MSSQL"
Database name..... "DE1"
Database user ID.. "de1"
Char.set.... "C"
SAP kernel....... 700
created (date)... "Oct 23 2007 00:33:51"
create on........ "NT 5.2 3790 Service Pack 1 x86 MS VC++ 14.00"
Database version. "SQL_Server_8.00 "
Patch level. 133
Patch text.. " "
Database............. "MSSQL 7.00.699 or higher, MSSQL 8.00.194"
SAP database version. 700
Operating system..... "Windows NT 5.0, Windows NT 5.1, Windows NT 5.2, Windows
NT 6.0"
Memory consumption
Roll.... 16192
EM...... 4189840
Heap.... 0
Page.... 0
MM Used. 1229856
MM Free. 2957360
User and Transaction
Client.............. 210
User................ 937048
Language Key........ "E"
Transaction......... " "
Transactions ID..... "68211f907e6911ddbfef005056833439"
Program............. "SAPLHRXSS_PER_MAC"
Screen.............. "SAPMSSY1 3004"
Screen Line......... 2
Information on caller of Remote Function Call (RFC):
System.............. "########"
Database Release.... 645
Kernel Release...... 645
Connection Type..... "E" (2=R/2, 3=ABAP System, E=Ext., R=Reg. Ext.)
Call Type........... "synchron and non-transactional (emode 0, imode 0)"
Inbound TID.........." "
Inbound Queue Name..." "
Outbound TID........." "
Outbound Queue Name.." "
Client.............. "###"
User................ "############"
Transaction......... " "
Call Program........." "
Function Module..... "HRXSS_PER_CLEANUP"
Call Destination.... "<unknown>"
Source Server....... "ERPDEV04"
Source IP Address... "10.88.1.9"
Additional information on RFC logon:
Trusted Relationship " "
Logon Return Code... 0
Trusted Return Code. 0
Note: For releases < 4.0, information on the RFC caller are often
only partially available.
Information on where terminated
Termination occurred in the ABAP program "SAPLHRXSS_PER_MAC" - in
"HRXSS_PER_CLEANUP".
The main program was "SAPMSSY1 ".
In the source code you have the termination point in line 13
of the (Include) program "LHRXSS_PER_MACU04".
The termination is caused because exception "CX_SY_REF_IS_INITIAL" occurred in
procedure "HRXSS_PER_CLEANUP" "(FUNCTION)", but it was neither handled locally
nor declared
in the RAISING clause of its signature.
The procedure is in program "SAPLHRXSS_PER_MAC "; its source code begins in
line
1 of the (Include program "LHRXSS_PER_MACU04 ".
Source Code Extract
Line
SourceCde
1
FUNCTION hrxss_per_cleanup.
2
3
""Local interface:
4
*" EXPORTING
5
*"     VALUE(MESSAGES) TYPE BAPIRETTAB
6
7
8
CALL METHOD mac_adapter->cleanup
9
   IMPORTING
10
     messages = messages.
11
12
TRY.
>>>>>
CALL METHOD xss_adapter->cleanup
14
15
CATCH CX_HRPA_VIOLATED_ASSERTION .
16
ENDTRY.
17
18
ENDFUNCTION.
Contents of system fields
Name
Val.
SY-SUBRC
0
SY-INDEX
2
SY-TABIX
0
SY-DBCNT
0
SY-FDPOS
0
SY-LSIND
0
SY-PAGNO
0
SY-LINNO
1
SY-COLNO
1
SY-PFKEY
SY-UCOMM
SY-TITLE
CPIC and RFC Control
SY-MSGTY
SY-MSGID
SY-MSGNO
000
SY-MSGV1
SY-MSGV2
SY-MSGV3
SY-MSGV4
SY-MODNO
0
SY-DATUM
20080909
SY-UZEIT
081916
SY-XPROG
SAPLHRXSS_PER_MAC
SY-XFORM
HRXSS_PER_CLEANUP
Active Calls/Events
No.   Ty.          Program                             Include                             Line
Name
4 FUNCTION     SAPLHRXSS_PER_MAC                   LHRXSS_PER_MACU04                      13
HRXSS_PER_CLEANUP
3 FORM         SAPLHRXSS_PER_MAC                   LHRXSS_PER_MACU04                       1
HRXSS_PER_CLEANUP
2 FORM         SAPMSSY1                            SAPMSSY1                               85
REMOTE_FUNCTION_CALL
1 MODULE (PBO) SAPMSSY1                            SAPMSSY1                               30
%_RFC_START
Chosen variables
Name
Val.
No.       4 Ty.          FUNCTION
Name HRXSS_PER_CLEANUP
MESSAGES
Table[initial]
%_DUMMY$$
2222
0000
0000
0000
No.       3 Ty.          FORM
Name HRXSS_PER_CLEANUP
SYST-REPID
SAPLHRXSS_PER_MAC
5454455555545544422222222222222222222222
310C82833F052FD1300000000000000000000000
0000000000000000000000000000000000000000
0000000000000000000000000000000000000000
%_%_MESSAGES
Table[initial]
No.       2 Ty.          FORM
Name REMOTE_FUNCTION_CALL
%_DUMMY$$
2222
0000
0000
0000
SY-REPID
SAPMSSY1
5454555322222222222222222222222222222222
310D339100000000000000000000000000000000
0000000000000000000000000000000000000000
0000000000000000000000000000000000000000
SYST-REPID
SAPMSSY1
5454555322222222222222222222222222222222
310D339100000000000000000000000000000000
0000000000000000000000000000000000000000
0000000000000000000000000000000000000000
HEADER
000000000000
000000000000
TYPE
3
0000
3000
SY-XPROG
SAPLHRXSS_PER_MAC
5454455555545544422222222222222222222222
310C82833F052FD1300000000000000000000000
0000000000000000000000000000000000000000
0000000000000000000000000000000000000000
RC
0
0000
0000
SY-XFORM
HRXSS_PER_CLEANUP
455555545544444552222222222222
82833F052F3C51E500000000000000
000000000000000000000000000000
000000000000000000000000000000
%_SPACE
2
0
0
0
No.       1 Ty.          MODULE (PBO)
Name %_RFC_START
%_PRINT
000                                                                                0###
2222333222222222222222222222222222222222222222222222222222222222222222222222222222222222223000
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
RFCTYPE_INTERNAL
3
0000
3000
Internal notes
The termination was triggered in function "method_call_iref"
of the SAP kernel, in line 2207 of the module
"//bas/700_REL/src/krn/runt/abmethod.c#8".
The internal operation just processed is "METH".
Internal mode was started at 20080909081916.
Active Calls in SAP Kernel
Lines of C Stack in Kernel (Structure Differs on Each Platform)
SAP (R) - R/3(TM) Callstack, Version 1.0
Copyright (C) SAP AG. All rights reserved.
Callstack without Exception:
App       : disp+work.EXE (pid=3864)
When      : 9/9/2008 8:19:16.162
Threads   : 2
Computer Name       : ERPDEV01
User Name           : SAPServiceDE1
Number of Processors: 4
Processor Type: AMD64 Family 15 Model 65 Stepping 2
Windows Version     : 5.2 Current Build: 3790
State Dump for Thread Id d90
FramePtr         ReturnAd         Param#1          Function Name
0000000007d1bb20 0000000077d704bf 000000003879a800 ntdll!ZwWaitForSingleObject
0000000007d1bbc0 0000000001722981 0000000000000180 kernel32!WaitForSingleObjectEx
0000000007d1be10 00000000006110c5 0000000000000001 disp+work!NTDebugProcess [ntstcdbg.c (501)]
0000000007d1be40 0000000000af8e9c 0000000000000001 disp+work!CTrcStack [dptstack.c (182)]
0000000007d1be90 0000000000afe0c0 0000000000000001 disp+work!rabax_CStackSave [abrabax.c (7091)]
0000000007d1c870 000000000081768a 0000000001adae28 disp+work!ab_rabax [abrabax.c (1231)]
0000000007d1c8d0 0000000000830b12 0000000000000000 disp+work!method_call_iref [abmethod.c (2215)]
0000000007d1ca50 0000000000a0bac7 0000000000000008 disp+work!ab_extri [abextri.c (554)]
0000000007d1caa0 0000000000ac830c 0000000000000008 disp+work!ab_xevent [abrunt1.c (281)]
0000000007d1cb30 000000000066f348 0000000000000008 disp+work!ab_dstep [abdynpro.c (492)]
0000000007d1ccb0 0000000000672f1d 000007fe571fc890 disp+work!dynpmcal [dymainstp.c (2403)]
0000000007d1cd40 000000000067291a 000007fe571414a0 disp+work!dynppbo0 [dymainstp.c (543)]
0000000007d1cdf0 00000000006320d5 0000000000000000 disp+work!dynprctl [dymainstp.c (360)]
0000000007d1fc30 00000000004d7393 0000000000000003 disp+work!dynpen00 [dymain.c (1629)]
0000000007d1feb0 000000000042d5a6 000000000a595080 disp+work!TskhLoop [thxxhead.c (4470)]
0000000007d1fee0 000000000040108d ffffffff00000003 disp+work!DpMain [dpxxdisp.c (1121)]
0000000007d1ff10 00000000019c7dd1 0000000000000000 disp+work!nlsui_main [thxxanf.c (84)]
0000000007d1ff70 0000000077d5964c 0000000000000000 disp+work!wmainCRTStartup [crtexe.c (498)]
0000000007d1ffa0 0000000000000000 00000000019c7c60 kernel32!BaseProcessStart
State Dump for Thread Id 1e0c
FramePtr         ReturnAd         Param#1          Function Name
000000000edffe40 0000000077d5f691 0000000007d86460 ntdll!NtFsControlFile
000000000edffeb0 00000000018ae00f 0000000000000000 kernel32!ConnectNamedPipe
000000000edfff40 000007ff7fc411c4 0000000000000000 disp+work!SigIMsgFunc [signt.c (679)]
000000000edfff70 0000000077d6b6da 0000000077d6b6a0 msvcrt!endthreadex
000000000edfffa0 0000000000000000 0000000000000000 kernel32!BaseThreadStart
List of ABAP programs affected
Index
Typ
Program
Group
Date
Time
Size
Lang.
0
Prg
SAPMSSY1
0
04/11/2005
09:27:15
22528
E
1
Prg
SAPLSYST
1
02/13/2005
17:31:56
35840
E
2
Prg
SAPLHRXSS_PER_MAC
2
07/03/2008
12:14:05
58368
E
3
Prg
CX_SY_REF_IS_INITIAL==========CP
3
07/05/2005
13:10:16
10240
E
4
Typ
SCX_SRCPOS
0
05/18/2004
14:07:11
2048
5
Prg
CX_DYNAMIC_CHECK==============CP
5
07/05/2005
13:10:16
10240
E
6
Prg
CX_ROOT=======================CP
6
02/06/2008
15:43:48
11264
E
7
Prg
CX_NO_CHECK===================CP
7
07/05/2005
13:10:16
10240
E
8
Prg
CX_SY_NO_HANDLER==============CP
8
07/05/2005
13:10:16
10240
E
9
Typ
SYST
0
09/09/2004
14:18:12
31744
Directory of Application Tables
Name                                     Date       Time       Lngth
Val.
Program SAPMSSY1
SYST                                       / /       : :     00004612
\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\x0001\0\0
ABAP Control Blocks (CONT)
Index
Name
Fl
PAR0
PAR1
PAR2
PAR3
PAR4
PAR5
PAR6
Source Code
Line
243
FUNC
03
001F
LHRXSS_PER_MACU03
1
244
PAR2
02
0000
001F
C000
LHRXSS_PER_MACU03
1
246
FUNC
13
0003
LHRXSS_PER_MACU03
1
247
PAR2
01
0000
0014
C001
LHRXSS_PER_MACU03
1
249
FUNC
FF
0000
LHRXSS_PER_MACU03
1
250
ENDF
00
0000
LHRXSS_PER_MACU03
1
251
00
0000
LHRXSS_PER_MACU03
1
252
STCK
02
C001
LHRXSS_PER_MACU03
1
253
CPOP
00
0000
LHRXSS_PER_MACU03
1
254
00
0000
LHRXSS_PER_MACU03
1
255
FUNP
3E
0000
0014
8000
0000
8000
0000
0000
LHRXSS_PER_MACU04
1
259
FUNP
80
0000
0000
0000
0000
0000
0000
0000
LHRXSS_PER_MACU04
1
>>>>>
METH
03
0000
0000
8006
0000
0000
0000
0000
LHRXSS_PER_MACU04
13
267
PAR2
00
0000
0001
0000
LHRXSS_PER_MACU04
13
269
FUNE
00
0000
LHRXSS_PER_MACU04
18
270
00
0000
LHRXSS_PER_MACU04
18
271
PERP
00
0000
LHRXSS_PER_MACU04
1
272
FUNC
03
E844
LHRXSS_PER_MACU04
1
273
FUNC
03
0020
LHRXSS_PER_MACU04
1
274
FUNC
13
0003
LHRXSS_PER_MACU04
1
Second Dump
Runtime Errors         DYNPRO_SEND_IN_BACKGROUND
Date and Time          09/09/2008 08:19:15
Short text
Screen output without connection to user.
What happened?
Error in the ABAP Application Program
The current ABAP program "SAPLSTRD" had to be terminated because it has
come across a statement that unfortunately cannot be executed.
What can you do?
Note down which actions and inputs caused the error.
To process the problem further, contact you SAP system
administrator.
Using Transaction ST22 for ABAP Dump Analysis, you can look
at and manage termination messages, and you can also
keep them for a long time.
Error analysis
During background processing, the system attempted to send a
screen to a user.
Current screen: "SAPLSTRD " 0351.
How to correct the error
If the error occurred in your own ABAP program or in an SAP
program you modified, try to remove the error.
If the error occures in a non-modified SAP program, you may be able to
find an interim solution in an SAP Note.
If you have access to SAP Notes, carry out a search with the following
keywords:
"DYNPRO_SEND_IN_BACKGROUND" " "
"SAPLSTRD" or " "
"SYSTEM-EXIT"
If you cannot solve the problem yourself and want to send an error
notification to SAP, include the following information:
1. The description of the current problem (short dump)
To save the description, choose "System->List->Save->Local File
(Unconverted)".
2. Corresponding system log
Display the system log by calling transaction SM21.
Restrict the time interval to 10 minutes before and five minutes
after the short dump. Then choose "System->List->Save->Local File
(Unconverted)".
3. If the problem occurs in a problem of your own or a modified SAP
program: The source code of the program
In the editor, choose "Utilities->More
Utilities->Upload/Download->Download".
4. Details about the conditions under which the error occurred or which
actions and input led to the error.
System environment
SAP-Release 700
Application server... "ERPDEV01"
Network address...... "10.88.1.6"
Operating system..... "Windows NT"
Release.............. "5.2"
Hardware type........ "4x AMD64 Level"
Character length.... 16 Bits
Pointer length....... 64 Bits
Work process number.. 1
Shortdump setting.... "full"
Database server... "ERPDEV01"
Database type..... "MSSQL"
Database name..... "DE1"
Database user ID.. "de1"
Char.set.... "C"
SAP kernel....... 700
created (date)... "Oct 23 2007 00:33:51"
create on........ "NT 5.2 3790 Service Pack 1 x86 MS VC++ 14.00"
Database version. "SQL_Server_8.00 "
Patch level. 133
Patch text.. " "
Database............. "MSSQL 7.00.699 or higher, MSSQL 8.00.194"
SAP database version. 700
Operating system..... "Windows NT 5.0, Windows NT 5.1, Windows NT 5.2, Windows
NT 6.0"
Memory consumption
Roll.... 16192
EM...... 12569520
Heap.... 0
Page.... 131072
MM Used. 8307376
MM Free. 4259072
User and Transaction
Client.............. 210
User................ 937048
Language Key........ "E"
Transaction......... " "
Transactions ID..... "68211f907e6911ddbfef005056833439"
Program............. "SAPLSTRD"
Screen.............. "SAPLSTRD 0351"
Screen Line......... 0
Information on caller of Remote Function Call (RFC):
System.............. "########"
Database Release.... 645
Kernel Release...... 700
Connection Type..... "E" (2=R/2, 3=ABAP System, E=Ext., R=Reg. Ext.)
Call Type........... "synchron and non-transactional (emode 0, imode 0)"
Inbound TID.........." "
Inbound Queue Name..." "
Outbound TID........." "
Outbound Queue Nam

Hello Abhiram,
Please i request weather you have assign 0105 - Communication infotype to ESSuser and
check the following JCos has been configured.
SAP_R3_Financials
SAP_R3_Financials_Metadata
SAP_R3_HumanResources
SAP_R3_HumanResources_MetaData
SAP_R3_SelfServiceGenerics
SAP_R3_SelfServiceGenerics_MetaData
SAP_R3_Travel
SAP_R3_Travel_MetaData
SAP_R3_SelfServiceGenerics_MetaDataFIN
SAP_R3_SelfServiceGenericsFIN
let me know this
points if problem solved
please close thread if problem solved
thanksyou,
regards
Vijai

Speeding up quadrature encoder read out

Hi,
I`m using a quadrature encoder together with a 6259 DAQ Card and BNC2110 Terminal Block.
I managed to have it working with the DAQ-Assistent at 80Mhz using the Counters and reading one value at a time. Before the DAQ-Assistent I used a DAQmx command to connect PFI10 and PFI9 as the BNC2110 Terminal only outputs PFI0-9. This works but it is really slow, the distance between each measurement point is around 6 us. The VI is in the attachement (AquadB_one_value.vi)
So I thought I might use the n-values version with the DAQ-Assistent but this does not work and I dont see any reason why, it is complaining about that connection between PFI10 and PFI9 which it didnt do before in the one-value-version. The VI is also in the attachement (AquadB_n_values.vi)
I also tried another method using a VI I was given some time ago and modified it but here the distance between each measurement point is also around 6us. This VI is also in the attachement (Counter - Read Encoder.vi)
Or am I missunderstanding something? The minimum achievable time distance between measurement points should be 1/80.000.000 s where of course the value can only differ 1/0/-1 because it has only calculated one new change in the A and B Signals right? I thought with using the n-values it is storing all the calculated values in the memory and I am transferring them afterwards for doing all the "post-processing"?
If I am wrong, how can I spped up the read-out of the calculated values any other way?
Best regards
Attachments:
AquadB_n_values.vi ‏56 KB
AquadB_one_value.vi ‏49 KB
Counter - Read Encoder.vi ‏98 KB

Hi Dani_munich,
I just realized that you asked the same question in our Service request. In the service request, I was missing out more information which I found them here by chance . I will further assist you in the SRQ you have created. I also sent you an email.
Regard
Anoj
Anoj Mubarak
National Instruments

RPM Measurement using Quadrature Encoder and PXI 6602 counter

Hi,
I am on a project at work where I need to verify the speed (in RPM) of an unloaded motor which can operate up to 1400 rpm. After doing some research, i determined that a quadrature encoder could be used to make the measurement. I am looking at this encoder http://sine.ni.com/nips/cds/view/p/lang/en/nid/205321.
I have a PXI 6602 counter/timer module in which I would like to interface to the quadrature encoder. I would like to create a VI that allows me to calculate the speed using the encoder. Can someone provide me with details of what needs to be in the VI or an example which can do this? At the most basic level, i want to calculate the speed on demand. After doing this, i would like to figure out how to quickly calculate the speed so that i can determine response time of the speed changing within sub-millisecond resolution (1 ms resolution max).
Further, i created a VI that allows me to change the pulse width of a 100 Hz pulse train at run-time which tells the motor controller the desired speed. I would like to be able to use this VI to change the speed of the motor and the first VI (that I am seeking help about) to calculate the response time (time between the initial speed and settling at the new setpoint).
I am familiar with the NI example finder, but have not been able to find an example that I can use.
Thanks,
Gary

Hey Gary,
I think for you setup, you should try using the Meas Dig Frequency - Low Freq 1 ctr. You can find it by searching example finder with 'low freq'. This vi tells you the frequency of a digital signal by sampling between two pulses and inverting the time between pulses. If you hook up your encoder to a counter and have that counter specified in the vi, it will be able to give you on demand readings of frequency (you can do some multiplication to get the rpm value, freq*60/pulses per revolution of encoder). A simple way to take continuous readings is to put a while loop around the daqmx read and the data output of the read. You can also replace the numeric indicator to a waveform chart to graphically display the change of frequency or rpm readings over time.
You should be able to integrate this as two separate tasks with the pulse train vi you created earlier.
Hope this helps
Luke W

Quadrature encoder synchronize sample

Using a USB-6251 to measure a quadrature encoder, i would like to determine the angle that an external discrete changes state. I tried connecting the discrete to a DIO input and using CVI PC code to read the encoder angle when the change of state occurs. The problem is the latency of the PC code which adds up to 4 degrees (with variability) to the measured angle. An ideal solution might be to trigger a measurement into a buffer within the USB-6251 when the discrete changes state, then read the value into the PC at a later time. Is this possible with the USB-6251?
Solved!
Go to Solution.

Thanks Adam,
I solved my problem using that idea with the addition of using buffered sampling and the discrete as a trigger. Committing the task to hardware also seems like a good idea but may not be required.
The setup code looks like this:
   // Start an Encoder channel on counter 1 to monitor the angle of label detector PNP edges
      status = DAQmxCreateTask("PNP Rising Edges",&pnpTaskHandle);
      strcpy (chanString, devName);
      strcat (chanString, "/ctr1");
      status = DAQmxCreateCIAngEncoderChan (pnpTaskHandle, chanString, "", DAQmx_Val_X4, 1, 0, DAQmx_Val_AHighBHigh,
                                                                              DAQmx_Val_Degrees, 4096, 0.0, "");
      sprintf (chanString, "/");
      strcat (chanString, devName);
      strcat (chanString, "/PFI1");
      status = DAQmxCfgSampClkTiming (pnpTaskHandle, chanString, 1000000, DAQmx_Val_Rising, DAQmx_Val_ContSamps, 10
                                      0000);
      if (status < 0)
      DAQmxGetErrorString (status, errString, 1000);
      DAQmxTaskControl (pnpTaskHandle, DAQmx_Val_Task_Commit);
      // Start the task
      status = DAQmxStartTask(pnpTaskHandle);
      angleTaskStarted = 1;
Reading the value looks like this:
      status = DAQmxReadCounterF64 (npnTaskHandle, DAQmx_Val_Auto, 0, npnEdgeArray, 1000, &npnSampsRead, 0);

Quadrature encoder with a non-NI board

I am attempting use an encoder with a non-NI board (Measurement Computing) and I am unsure how to interface the encoder output from the board with LabView. I have the VIs for the board which allow the board to interface with LabView,. I essentially need a VI to decode the quadrature, the ones in the tutorials were not very helpful or insightful.

Hello Mystery,
Take a look at the section “Velocity and Acceleration Calculations” in this devzone. While the article itself applies to CompactRIO, the equations used in the above section can help you determine how to convert the counter output into a velocity measurement.
Does the counter value increase when you rotate the encoder in one direction and decrease when you rotate in the other direction? This is essentially position measurement. By knowing the number of ticks per revolution as well as the starting position of the encoder, you can determine the current rotation position. For velocity, there is a little more to the measurement. The concept relies on taking a counter measurement in a periodic manner. Then you can use the number of encoder pulses that have occurred over that period of time to calculate velocity. The document I linked about shows how to convert the number of encoder pulses over a fixed period of time into RPM which can be later converted into angular velocity. Hope this helps.
Regards,
Browning G
FlexRIO R&D

Simulate quadrature encoder output without hardware

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