Skip to Content

Register Login

Industry Online Support

Technical Forum

Navigation

Help on STL....

Created by: ivan_euler at: 12/27/2009 12:20 AM (5 Replies)

Rating (0)

Thanks 1

6 Entries

12/27/2009 12:20 AM	Rate (0)
ivan_euler Posts: 54 Rating: (0)	This is a code given to mee by one of the expert here... When i try to run the code in simulation mode the cpu fail........System failure..... When i try to run M 100,0 the plc goes to stop mode.... I try to analyse it and i think the problems lies in the pointer creation...Any help will be highly appreciated.. This is used for history archiving..... AM100.0//positiveedgesignaloffinishedproccess JCN_00x TAR1MD110//saveregisterAR1inmemory TAR2MD114//saveregisterAR2inmemory LMD102//loadindexvalueintomemory LL#1//subtract1fromindexvaluetogetcorrectpointer(DBstartsfrom0) -D LL#2//multiplyvalueby2incaseifourproccessvaluesare2byteslong *D SLD3//moveby3placestoleft(needforpointerconstruction,lookhelpforfurtherinfo) LAR1P#DBX0.0//makepointertoDB +AR1 OPNDB50//openDBwhereyoustoreproccessvalues LW[AR1,P#0.0]//ifindexis1thenloadDB50.DBW0 TW[AR1,P#2.0]//transfervaluetoDB50.DBW2 LPIW256//loadcurrectproccessvalue(PIW256isanexample) TW[AR1,P#0.0]//transfernewvaluetoDB50.DBW0 LAR1MD110//restoreregisterAR1 LAR2MD114//restoreregisterAR2 LMD102//loadindexvalue LL#1//load1 +D//incrementindexby1 TMD102//transferindexvalueback L5//load5 <=D//checkifindexvalueislessorequalof5 JC_00y LL#1//ifequalrestartindexfrom1again TMD102//transfer1toindexvalue _00y:NOP0 _00x:NOP0
ivan_euler Posts: 54 Rating: (0)
Suggestion To thank Quote Answer

12/27/2009 1:22 AM	Rate (0)
Sydney Gold Member Joined: 1/4/2008 Last visit: 3/8/2023 Posts: 703 Rating: (96)	Hello, for the first sight the code isn't optimal, but this thread is not about an optimalization. The reason of a CPU stop is written in the Diagnostic Buffer. You can find it inthe Module information - Ctrl+D or menu PLC->Module Information in the STL editor or rightclick in Simatic Manager. My tip is that you haven't initialised the counter (MD 102) to 1 so forthe first time there is a zero, in thecode it's decremented by one and used as a pointer so it access the non existing address in the DB. Regards Sydney

Suggestion To thank Quote Answer

1/3/2010 1:17 AM	Rate (0)
ivan_euler Posts: 54 Rating: (0)	hello guys happy new year.... Im still having a problem even though i iniatialized the index variable to 1.....Still it seems a problem......anybody ?Kindly help me out AM100.1 //positiveedgesignaloffinishedproccess FP M 100.0// positive edge detection JCN_00x TAR1MD110//saveregisterAR1inmemory TAR2MD114//saveregisterAR2inmemory LMD102//loadindexvalueintomemory LL#1//subtract1fromindexvaluetogetcorrectpointer(DBstartsfrom0) -D LL#2//multiplyvalueby2incaseifourproccessvaluesare2byteslong *D SLD3//moveby3placestoleft(needforpointerconstruction,lookhelpforfurtherinfo) LAR1P#DBX0.0//makepointertoDB +AR1 OPNDB50//openDBwhereyoustoreproccessvalues LW[AR1,P#0.0]//ifindexis1thenloadDB50.DBW0 TW[AR1,P#2.0]//transfervaluetoDB50.DBW2 LPIW256//loadcurrectproccessvalue(PIW256isanexample) TW[AR1,P#0.0]//transfernewvaluetoDB50.DBW0 LAR1MD110//restoreregisterAR1 LAR2MD114//restoreregisterAR2 LMD102//loadindexvalue LL#1//load1 +D//incrementindexby1 TMD102//transferindexvalueback L5//load5 <=D//checkifindexvalueislessorequalof5 JC_00y LL#1//ifequalrestartindexfrom1again TMD102//transfer1toindexvalue _00y:NOP0 _00x:NOP0
ivan_euler Posts: 54 Rating: (0)
Suggestion To thank Quote Answer

1/3/2010 4:20 PM	Rate (0)
dchartier Grandmaster-Expert Joined: 9/27/2006 Last visit: 6/6/2023 Posts: 12036 Rating: (2595)	Hello Ivan; Sydney Hello, ...The reason of a CPU stop is written in the Diagnostic Buffer. You can find it inthe Module information - Ctrl+D or menu PLC->Module Information in the STL editor or rightclick in Simatic Manager.... Regards Sydney Could you please use the fundamental tip provided by Sydney and tell us what is written to the diagnostic buffer once the CPU goes to STOP mode? This is the first step in diagnostics for a S7-300 CPU. Hope this helps, Daniel Chartier

Suggestion To thank Quote Answer
This contribution was helpful to 1 thankful Users Sydney

1/4/2010 3:04 PM	Rate (0)
Sydney Gold Member Joined: 1/4/2008 Last visit: 3/8/2023 Posts: 703 Rating: (96)	Hello, as addition:when a CPU goes to stop mode, in mentioned Module Information you canopen the Stacks tab, where can be found the actual data in accumulators, registers and interrupted block - if you click on the Open Block button it will show you directly on which line in STL it ends program execution... Regards Sydney

Suggestion To thank Quote Answer

1/5/2010 2:11 PM	Rate (0)
fritz Diamond Expert Joined: 10/7/2005 Last visit: 6/6/2023 Posts: 2966 Rating: (1025)	Hello ivan_euler as Sydney quite rightly already said, the code implementation isn't "optimal" but will work IF MD102has a valid a value in it (in your case this meanseither 1, 2, 3, 4 or 5). The other conditions that need to be fullfiled are: - DB50 MUST exist in the PLC and MUST be at least 12 Bytes long. - PIW256 must "exist". Assuming the above conditions are met your code will work without problems (note though that MD102 will be reset to zero after a PLC restart unless it is part of the retentive memory bytes area). Having said the above, I'm not too sure about the intent/desired functionality of your code. The logic does sort of create ringbuffer (last 5 AI values are buffered in DB50.DBW0 to DB50.DBW8 except for the one that is "spat out" in DB50.DBW10) and every 5th AI value is "spat out" (or 'sampled") in DB50.DBW10. I hope this helps
	Cheers fritz The advice and opinion given in this thread is that of the author and does not necessarily reflect the views of I S Systems Pty Limited. To find out how I S Systems can help you with your automation needs please visit www.issystems.com.au.
Suggestion To thank Quote Answer

|

Share this page:

Share this page on...

Follow us on