Post by ihatemaryfisher on Sorting array of any-sized structure ^{CODESYS Forge talk (Post)}
In my machine's operation, I need to display multiples tables containing arrays of structured variables. The arrays change during operation, and my supervisor has advised me to write a new bubble-sort for each array. I think I can make a function to sort an array of any data type. This was my own project, and I'm a relatively new coder. I want to know the weaknesses in my approach, and a better method, if one exists. As far as I can test, the function accepts an array of a structured variable of any size, and sort it by any VAR in that structure. But it relies heavily on pointers, which I've heard are bad practice? Function call: // SORT BY BYTE-SIZED VAR IF xDoIt[6] THEN FUNBubbleSortSansBuffer( IN_pbySourcePointer := ADR(astArray[1]), // address of first byte in first element of array IN_pbyComparePointer:= ADR(astArray[1].byCompByte), // points to first byte of the comparing variable (variable you sort by) IN_uiStructureSize := SIZEOF(TYPE_STRUCTURE), // size, in bytes, of the structured variable IN_uiCompareSize := SIZEOF(astArray[1].byCompByte), // size, in bytes, of the comparing variable (variable you sort by) diArrayElements := UPPER_BOUND(astArray,1), // number of elements in array IN_xSmallToLarge := xSortOrder // whether to sort by small2large or large2small ); END_IF Function: FUNCTION FUNBubbleSortSansBuffer : BOOL VAR_INPUT IN_pbySourcePointer : POINTER TO BYTE; // points to beginning of array (first byte of first element) IN_pbyComparePointer: POINTER TO BYTE; // points to first byte of the comparing variable (variable you sort by) IN_uiStructureSize : UINT; // size, in bytes, of the structured variable IN_uiCompareSize : UINT; // size, in bytes, of the comparing variable (variable you sort by) diArrayElements : DINT; // number of elements in array IN_xSmallToLarge : BOOL; // whether to sort by small2large or large2small END_VAR VAR j : DINT; // repeat iteration over array until array ends i : DINT; // iterarte over array, swapping when necesary k : DINT; // iterator from 1 to size of structure (stepping 'through' a single element in array) dwSize : DWORD; // internal var for use in MEMUtils.MemCpy(<size>) // FOR SORTING BY BYTE VAR pbySourcePointer : POINTER TO BYTE; pbySourcePointer2 : POINTER TO BYTE; pbyComparePointer : POINTER TO BYTE; pbyComparePointer2 : POINTER TO BYTE; pbyPointerToBuffer : POINTER TO BYTE; // pointer to single byte buffer byBufferByte : BYTE; // single byte buffer END_VAR dwSize := UINT_TO_DWORD(IN_uiStructureSize); // get structure size (number of bytes) pbyPointerToBuffer := ADR(byBufferByte); // assign pointer to address of buffer byte (because MEMUtils.MemCpy requires a pointer input) CASE IN_uiCompareSize OF // depending on the size of the VAR to sort by (current functionality for BYTE and WORD/INT 1: // BYTE (8 BIT) FOR j := 1 TO diArrayElements DO // for number of elements in array FOR i := 1 TO (diArrayElements-1) DO // same thing, but row[i+1] row is included in swap logic pbySourcePointer := IN_pbySourcePointer + dwSize*(i-1); // point at #1 byte in array element[i] pbySourcePointer2 := pbySourcePointer + dwSize; // point at #1 byte in array element[i+1] // NOTE: because of memory locations, each array element is offset from one another by a number of bytes equal to the size of the structure // We can "walk" from array[i] to array[i+1] via steps equal to the size of the structure // e.g., ADR(array[i+1]) == ADR(array[i]) + SIZEOF([array datatype]) pbyComparePointer := IN_pbyComparePointer + dwSize*(i-1); // point to sorting variable in array element[i] pbyComparePointer2 := pbyComparePointer + dwSize; // point to sorting variable in array element[i+1] // using sort order (small -> large/large -> small) IF SEL(IN_xSmallToLarge, (pbyComparePointer2^ > pbyComparePointer^),(pbyComparePointer2^ < pbyComparePointer^)) THEN // This is where it gets tricky. We've identified pointers for the starting bytes of aArray[i] and aArray[i+1] // and we know the size of aArray[i]. We are going to swap individual bytes, one at a time, from aArray[i] and aArray[i+1] // this allows us to use only a single byte var as a buffer or temporary data storage // e.g., consider a structure consisting of a word, a byte, and a string. it is stored like this // |------WORD-------| |--BYTE-| |STRING------...| // astArray[1] == 1000 0100 0010 0001 1100 0011 1010 1010.... etc // astArray[2] == 0001 0010 0100 1000 0011 1100 0101 0101.... etc // performing a single swap (copy into a buffer, etc.) of the first byte of each array element creates this // astArray[1] == 0001 0100 0010 0001 1100 0011 1010 1010.... etc // astArray[2] == 1000 0010 0100 1000 0011 1100 0101 0101.... etc // incrementing the pointer adresses for the swap by 1 and swapping again swaps the next byte in each array element // astArray[1] == 0001 0010 0010 0001 1100 0011 1010 1010.... etc // astArray[2] == 1000 0100 0100 1000 0011 1100 0101 0101.... etc // continuing this from k to SIZEOF(TYPE_STRUCTURE) results in a toally swapped row FOR k := 1 TO IN_uiStructureSize DO // copy single byte[k] of array element 1 to buffer MEMUtils.MemCpy(pbyDest := (pbyPointerToBuffer), pbySrc := (pbySourcePointer+k-1), dwSize := 1); // copy single byte[k] of array element 2 to 1 MEMUtils.MemCpy(pbyDest := pbySourcePointer+k-1, pbySrc := (pbySourcePointer2+k-1), dwSize := 1); // copy buffer to byte[k] array element 2 MEMUtils.MemCpy(pbyDest := (pbySourcePointer2+k-1), pbySrc := pbyPointerToBuffer, dwSize := 1); END_FOR END_IF END_FOR END_FOR
Last updated: 2023-08-17

addressin an array of byte containing bits of type bool ^{CODESYS Forge talk (Thread)}
addressin an array of byte containing bits of type bool
Last updated: 2018-11-14

Is it possible for a byte to have a negative sign? ^{CODESYS Forge talk (Thread)}
Is it possible for a byte to have a negative sign?
Last updated: 2019-10-31

Post by smartcoco on Bit / Bool data types in function parameters ^{CODESYS Forge talk (Post)}
Memory addressing is measured in bytes, with BOOL occupying one byte. BIT is quite unique as it occupies one bit. So, try not to use BIT in the program. You can use the Unpack function to solve your problem.
Last updated: 2024-01-18

Post by chirag on About byte swap and convert into 16 bits ^{CODESYS Forge talk (Post)}
Hello, I have %QB0 8 high bits and %QB1 8 low bits . How can i swap bits %QB0 and %QB1 for requirment positions in a 16-bit value ? after that i need %QB0 and %QB1 in to 16bits . For that, i need help. Please see attached pictures for your reference. Thanks in advance.
Last updated: 2023-12-04

Post by bjarne-pagaard on Codesys v3.5 Sint to byte ^{CODESYS Forge talk (Post)}
Hi A SINT is a short (signed) integer. It is already only 1 byte - so you should have no problem casting it to a byte like so: bMyByte := TO_BYTE(sintMyShortInt); If you have a regular INT you want to put in 2 bytes - there are a lot of ways you can do this. A Union is certainly one of them. You could have a union with 2 memebers: An array of 2 bytes as one member, and an integer value as another member. Another way would be to look at MEMCPY to put the value into your CAN-message. .. or create a function to take your input value as input, and giving you 2 individual bytes as output. This could be handy if you need to change the byte-order. Integer data types: https://help.codesys.com/webapp/_cds_datatype_integer;product=codesys;version=3.5.17.0 -Bjarne
Last updated: 2024-04-24

Übertragen von Symbolnamen in Steuerkonfiguartion in ... ^{CODESYS Forge talk (Thread)}
Übertragen von Symbolnamen in Steuerkonfiguartion in ...
Last updated: 2011-05-15

No packages in IP in Codesys ^{CODESYS Forge talk (Thread)}
No packages in IP in Codesys
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sprung in bestimmten schritt in AS ^{CODESYS Forge talk (Thread)}
sprung in bestimmten schritt in AS
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Post by dhumphries on Not able to see input data coming from eip adapter on codesys ^{CODESYS Forge talk (Post)}
The green icon with an ! next to the device is concerning. Is the data type correct for the input, you are using a byte input but the description says string. Is there anything useful in the status tab?
Last updated: 2024-03-06

Post by abjha1998 on Codesys v3.5 Sint to byte ^{CODESYS Forge talk (Post)}
Hi everyone, I have been doing a project where I have to send CAN messages from WAGO plc pf200 in BYtes. The signed integer needs to be unpacked into two bytes. so far I have tried Union but that has not worked with me
Last updated: 2024-04-22

Post by ph0010421 on How to manage variable types larger than 64 bits - Ethernet/IP ^{CODESYS Forge talk (Post)}
So it's currently mapped to an array of BYTES? Can you create a UNION? TYPE sBytesString : UNION AsBytes: ARRAY[0..127] OF BYTE; AsString: STRING(128); END_UNION END_TYPE Map it to the bytes, read it in the STRING!
Last updated: 2024-09-23

Post by struccc on Bibliothek: floatingpointutils ^{CODESYS Forge talk (Post)}
The issue s the byte order typically in this case. Can be especially problematic with floating point numbers - even more tricky if transferred with a word based protocol. It is a peasant way to try out the alternatives, dword order can be a-b-c-d, b-a-d-c, c-d-a-b, d-c-b-a where a is the most significant, d is the least significant byte. So all you need is to swap the bytes in your dword, until you get the expected result. If you don't want to mess writing code for this, I'd recommend CAA_Memory library for that: MEM.ReverseBYTEsInDWORD and MEM.ReverseWORDsInDWORD functions would definitively do the trick. Otherwise, can do like this: VAR dwIn : DWORD := 16#11223344; dwOut : DWORD; rOut : REAL; pIN : POINTER TO BYTE; pOUT : POINTER TO BYTE; END_VAR pIN := ADR(dwIn); //pOUt := ADR(dwOut); pOUt := ADR(rOut); pOut[0] := pIN[3]; pOut[1] := pIN[2]; pOut[2] := pIN[1]; pOut[3] := pIN[0]; Ugly, but does the job...
Last updated: 1 day ago

Variables $placeholders$ in visualisations, like in v.2.x ? ^{CODESYS Forge talk (Thread)}
Variables $placeholders$ in visualisations, like in v.2.x ?
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Defining two variable in one rectangle box in Visualization ^{CODESYS Forge talk (Thread)}
Defining two variable in one rectangle box in Visualization
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Compilerdefines works in application properties but not in POU properties ^{CODESYS Forge talk (Thread)}
Compilerdefines works in application properties but not in POU properties
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Eingabe in die Visualisierung in ein Array ^{CODESYS Forge talk (Thread)}
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Device related functions - in library or in Main Program ? ^{CODESYS Forge talk (Thread)}
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use globals in multiple actions in SFC ^{CODESYS Forge talk (Thread)}
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How to use retentive option in timer in codesys v3.5? ^{CODESYS Forge talk (Thread)}
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I need help in SCF - Beginner in Codesys ^{CODESYS Forge talk (Thread)}
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where is my IN working in CFC macro ^{CODESYS Forge talk (Thread)}
where is my IN working in CFC macro
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Tabelle in einer Visu in einem Lib-Projekt ^{CODESYS Forge talk (Thread)}
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Unbekanntes Symbol in der Netzwerk Darstellung in Codesys ^{CODESYS Forge talk (Thread)}
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error in device modbus in update sp19 ^{CODESYS Forge talk (Thread)}
error in device modbus in update sp19
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