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Looping char Array in STL

Created by: Gediminas at: 5/8/2012 10:29 AM (5 Replies)

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5/8/2012 10:29 AM	Rate (0)
Gediminas Posts: 2 Rating: (0)	Hello, I'm new in PLC programming soI need a little help... I have an array of char(ARRAY[0..2047] of CHAR) in DataBlock and I need to scan that array for specific character or character combination... And i need to get adress of the result. Ex: Find the adress of the first char 'b' in the array (of random data). And find the adress of the char 'o' followed by char 'z'... Something like that. My try: In OB1 i have: CALL "Func" UID:="Block1".array1 in FC1 i have (from some example): (UID is sype ANY) TAR1 #_ar1 L P##UID LAR1 L W [AR1,P#0.0] T #_wPLC_Type L W [AR1,P#2.0] T #_iLen L W [AR1,P#4.0] T #_iDB L D [AR1,P#6.0] AD DW#16#FFFFFF SRD 3 T #_dwArea from this i get data type, length of the data, DB number, and start adress.. And then what? :) Is there a simple way to loop the array with like: L DB1.array1[n] where n is variable (like in C++, C#, pascal, etc..?). And not using pointers (which I'm not yet familiar with)
Gediminas Posts: 2 Rating: (0)	Last edited by: Gediminas at: 5/8/2012 10:32 AM
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5/8/2012 11:29 AM	Rate (0)
KayBee Posts: 241 Rating: (7)	You need to learn about Pointer & Loop to do this task. It should easy once you do. I gave a outline idea for you; this is not tested prgram just 'start up idea'; L P##Pointer //Load the integer constant (32 bit) into ACCU 1. T MD 20 //Transfer the contents from ACCU 1 into MD20 (initialization). L 5 //Loop //Load number of loop cycles into ACCU 1-L. NEXT: T MW 10 //Jump label = loop start / transfer ACCU 1-L to loop counter. L L#0 L L#0 L MD 20 // Check this statment, load data from Pointer MD20 L 'C' ==I //Equal JC GOT //Transfer the multiplication result to MD20. L MW 10 //Load contents of loop counter into ACCU 1. LOOP NEXT //Decrement the contents of ACCU 1 and jump to the NEXT jump label if ACCU 1-L > 0. NGOT: NOP 0 //Not found C //found until end GOT: NOP 0 //C fund
KayBee Posts: 241 Rating: (7)
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5/8/2012 11:38 AM	Rate (0)
hdhosseini Diamond Expert Joined: 1/28/2009 Last visit: 6/6/2023 Posts: 6804 Rating: (1346)	Gediminas Is there a simple way to loop the array with like: L DB1.array1[n] where n is variable (like in C++, C#, pascal, etc..?). And not using pointers (which I'm not yet familiar with) Hello Gediminas, "SCL optional package" is high level programming and it is somehow similar to PASCAL.Check the following clustered posts for assessing functionality. SCL Starting Point Best regards, Hamid Hosseini
	Demo Channel on Youtube
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5/8/2012 12:21 PM	Rate (0)
Darius Platinum Member Joined: 9/28/2005 Last visit: 5/2/2023 Posts: 2957 Rating: (242)	KayBee You need to learn about Pointer & Loop to do this task. It should easy once you do. I gave a outline idea for you; this is not tested prgram just 'start up idea'; L P##Pointer //Load the integer constant (32 bit) into ACCU 1. T MD 20 //Transfer the contents from ACCU 1 into MD20 (initialization). L 5 //Loop //Load number of loop cycles into ACCU 1-L. NEXT: T MW 10 //Jump label = loop start / transfer ACCU 1-L to loop counter. L L#0 L L#0 L MD 20 // Check this statment, load data from Pointer MD20 L 'C' ==I //Equal JC GOT //Transfer the multiplication result to MD20. L MW 10 //Load contents of loop counter into ACCU 1. LOOP NEXT //Decrement the contents of ACCU 1 and jump to the NEXT jump label if ACCU 1-L > 0. NGOT: NOP 0 //Not found C //found until end GOT: NOP 0 //C fund In addition I can say that making loops is not a very good idea especially for array of 2048 bytes. If it is not critical better is to make calculations every scan rather that make a loop. In wors case it will take 2048xscan time, but you can use some done bit to indicate that search throught array was finished. If you will use loop for 2048 array elements that it can increate scan time dramatically. Especially if you do it frequent then its not good. Also if you have some PID control on the same PLC then better is to refuse using loops.
	Best regards, Darius
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This contribution was helpful to 1 thankful Users KayBee

5/10/2012 7:59 AM	Rate (0)
Aret Posts: 2348 Rating: (259)	I totally agree with Darius. Maybe you can do required searching on filling this array?
Aret Posts: 2348 Rating: (259)
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This contribution was helpful to 1 thankful Users Darius

5/22/2012 9:26 AM	Rate (0)
Gediminas Posts: 2 Rating: (0)	OB1 code: CALL FB 1 , DB4 UID :="Blokas1".masyvas Find1 :="Data Block Var".Paieska.find1 Result:="Data Block Var".find1reznoloop CALL "Func" UID :="Blokas1".masyvas Find1 :="Data Block Var".Paieska.find1 RET_VAL:="Data Block Var".find1rez FC1 (Func) code: Network1: L L#-1 T #RET_VAL L P##UID LAR1 L W [AR1,P#4.0] T #iDB OPN DB [#iDB] L W [AR1,P#2.0] T #iLen L D [AR1,P#6.0] LAR1 L #iLen F: T #iLen L B [AR1,P#0.0] L #Find1 ==I JC fnd +AR1 P#1.0 L #iLen LOOP F JU exit fnd: TAR1 AD DW#16#FFFFF SRD 3 T #RET_VAL SET JU ex exit: CLR ex: SAVE With FC1 everything works fine, but it uses loops so it's not realy good... In FB1 i tried to do the same but without loops... Is this correct? FB1 code: Network1: L #_cLastFind1 L #Find1 ==I JC ex L L#-1 T #Result L P##UID LAR1 L W [AR1,P#4.0] T #iDB OPN DB [#iDB] L W [AR1,P#2.0] T #iLen L #_iScanNr >I JCN nfnd L D [AR1,P#6.0] LAR1 L #_iScanNr SLD 3 OD DW#16#84000000 LAR1 L B [AR1,P#0.0] L #Find1 ==I JC fnd JU exnf nfnd: NOP 0 L #Find1 T #_cLastFind1 L 0 T #_iScanNr JU exit fnd: TAR1 AD DW#16#FFFFF SRD 3 T #Result SET JU exf ex: NOP 0 L 0 T #_iScanNr JU exit exf: SAVE L B [AR1,P#0.0] T #_cLastFind1 L 0 T #_iScanNr JU exit exnf: NOP 0 L #_iScanNr + 1 T #_iScanNr exit: NOP 0
Gediminas Posts: 2 Rating: (0)
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