Post by smeitink on Timeout Error in Modbus Communication with WAGO PFC200 and iEM2050 Meter using 750-652 Module ^{CODESYS Forge talk (Post)}
Hi all, I'm looking for help with an issue I've come across while trying to facilitate Modbus communication between a WAGO PFC200 PLC using a 750-652 communication module and an iEM2050 Series Single Phase Energy Meter. I believe to have everything wired and setup correcty, but I keep running into a "Error time out" message, and by now I don't really know what else to try. My setup is as follows: A PFC200 Wago PLC, which has 2 750-652 Serial Interfaces extension modules connected to its field bus. I'm using one of these to talk to a Schneider iEM2050 - kWh-meter over modbus. I have connected terminal 23 (A) of the iEM2050 to connector 6 (A) on the 750-652. I have connected terminal 24 (B) of the iEM2050 to connector 2 (B) of the 750-652. I'm using 200mm of twisted together wires to connected them both, and I have placed a 120 ohm resistor between A and B at both ends. I've attached relevant pinout images to this post. I then wrote a simple program that configures the Mobus port, as per the datasheet of the iEM2050. You can find an image of the relavent page attached to this post too. This is my program: PROGRAM PLC_PRG VAR Master: FbMbMasterSerial; xIsConnected: BOOL; xError: BOOL; iIndex: INT := 1; xTrigger: BOOL; utQuery : typMbQuery := ( bUnitId := 1, // The Modbus unit or slave address bFunctionCode := 4, // Function code for reading input registers uiReadAddress := 1829, // adress for the Power on off counter uiReadQuantity := 1 // Quantity of registers to read ); iStep: INT; oStatusModbus: WagoSysErrorBase.FbResult; utResponseModbus: typMbResponse; xConnect: BOOL := FALSE; delayTimer: TON; END_VAR Master( xConnect:= xConnect, I_Port:= _750_652_24_1, udiBaudrate:= 9600, usiDataBits:= 8, eParity:= WagoTypesCom.eTTYParity.Even, eStopBits:= WagoTypesCom.eTTYStopBits.One, eHandshake:= WagoTypesCom.eTTYHandshake.None, ePhysical:= WagoTypesCom.eTTYPhysicalLayer.RS485_HalfDuplex, xIsConnected=> xIsConnected, xError=> xError, oStatus=> oStatusModbus, eFrameType:= WagoAppPlcModbus.eMbFrameType.RTU, tTimeOut:= T#5S, utQuery:= utQuery, xTrigger:= xTrigger, utResponse:= utResponseModbus); delayTimer(IN := TRUE, PT := T#3S); // Use the Q output of the timer to set xConnect after the delay IF delayTimer.Q THEN xConnect := TRUE; END_IF CASE iStep OF 0: //Wacht totdat de master de poort geopend heeft IF xIsConnected THEN iStep := 1; END_IF 1: //Stuur request naar de slave xTrigger := TRUE; iStep := 2; 2: //Wacht totdat de master klaar is met het afhandelen van de request IF NOT xTrigger THEN iStep := 3; END_IF END_CASE The TON delay before opening the port is due to a an error I encountered when opening it straight away. This seems to be a bug, as described here. However, the TON solved that particular issue. I tried reading multiple registers, but like I said, I still always end up with the "Error time out". What else can I test or try at this point?
Last updated: 2024-02-24

Post by struccc on Inheritence of struct, ^{CODESYS Forge talk (Post)}
Strangely reminds me to my struggles... Want to do something "Elegant", reusable, universal, practical... In CODESYS??? 🙃 First of all, before you get too deep into this: If you could find a way, to make a "universal" log entry object, containing the variable length data itself, you wouldn't be able to store them in an array, or access them like an array, or pass them by value as a type. (please correct me, if I'm wrong, incorrect, or not precise). Because... Basically you can't declare a type with variable memory footprint. This is a very deeply embedded characteristic of CODESYS, and all IEC 61131-3 systems, and it has many reasons behind. And yes, it is a very common trap / mistake, to forget about. So, with a log entry - I guess - it's pretty much the purpose: store data and metadata together, and then handle it in a uniform way. There are ways to handle this, really depends on what is the purpose. For example: 1. Entries with fixed length (Maybe it is not as evil as it looks for the first time. Depends on the situation, but definitely the fastest and easiest code) You can have your base object, with an internal, fixed length string or byte array variable. I would go with a string, and call it _Data.; And then you can make properties, like As_Bool, As_Int, As_Real... In the 'set' accessors, you can do like: pReal := ADR(_Data); // POINTER TO REAL As_Real := pReal^; In the 'get' accessors, evidently: pReal := ADR(_Data); // POINTER TO REAL pReal^ := AS_Real; Or, can use ANY type, if you are not obsessed with variable / property like access: 2. Fixed length, but nicer First, some disadvantage to any values: - You can only assign values with write access. No literals, constants, etc... - Can only be used as input variable of function or function_block - Therefore, stg you could reach: LogEntry.Initialize (stVariable|rVariable|iVariable|xVariable); Just a quick example (it's funny to play with ANY): Be careful it was not tested. I'm sure can be done better, please feel free to comment FUNCTION_BLOCK FB_LogEntry VAR_INPUT MsgClass : UDINT; // Like DEBUG, WARN, ERR... MsgCode : UDINT; // Like Errors.ERR_FAILED MsgTS : DT; // The timestamp END_VAR VAR _Data : STRING(80); // Our data container... _Descr : __SYSTEM.AnyType; // A standard descriptor for our data, containing TYPE_CLASS, address and size END_VAR METHOD SET_Value : BOOL VAR_INPUT anyValue : ANY; END_VAR VAR I : DINT; diSize : DINT; pStr : POINTER TO STRING; END_VAR // Check what did we receive in anyValue. diSize := anyValue.diSize; // We use constant __SYSTEM.TYPE_CLASS to identify the received data type CASE anyValue.TypeClass OF // Maybe we don't want to store references, pointers... and who knows what else... __SYSTEM.TYPE_CLASS.TYPE_REFERENCE, __SYSTEM.TYPE_CLASS.TYPE_POINTER : SET_Value := FALSE; // For the planned types we will be just fine. TYPE_CLASS.TYPE_BOOL, TYPE_CLASS.TYPE_INT, TYPE_CLASS.TYPE_REAL : SET_Value := TRUE; // Optionally string can be handled separately, maybe we have received STRING(255), but practically it is shorter than 80 bytes... TYPE_CLASS.TYPE_STRING : pStr := anyValue.pValue; diSize := MIN(anyValue.diSize, LEN(pStr^) + 1); // Get the actual size, and rewrite the received structure member diSize := MIN(SIZEOF(_Data), diSize); // Can chop down the received string to our length... SET_Value := TRUE; // Maybe want to play a little bit more here, to narrow down or convert datatypes, etc... // Or just reject any other datatype ELSE SET_Value := FALSE; RETURN; END_CASE // Fail, if the received value is still larger than our container... IF diSize > SIZEOF(_Data) THEN SET_Value := FALSE; END_IF // Here we should be ok, just set up the _DataType structure, and copy store the data IF SET_Value THEN THIS^._Descr.TypeClass := anyValue.TypeClass; // The typeclass is already filtered THIS^._Descr.diSize := diSize; // Set the (adjusted) size THIS^._Descr.pValue := ADR(_Data); // This will not change, just to be sure {IF defined (pou:SysMem.SysMemCpy)} SysMem.SysMemCpy(_DataType.pValue, anyValue.pValue, TO_UDINT(anyValue.diSize)); {ELSE} // An ugly replacement MemCpy FOR I:=0 TO diSize - 1 DO _Descr.pValue[I] := anyValue.pValue[i]; END_FOR {END_IF} // Otherwise, in case of failure maybe better set an empty value (overwrite the former data descriptor) ELSE THIS^._Descr.TypeClass := TYPE_CLASS.TYPE_NONE; THIS^._Descr.pValue := ADR(_Data); THIS^._Descr.diSize := 0; END_IF METHOD GET_Value : BOOL VAR_INPUT anyValue : ANY; END_VAR VAR I : DINT; END_VAR // We just have to serve the data, using the __System.AnyType structure received // Roughly we can say: IF anyValue.TypeClass = _Descr.TypeClass AND anyValue.pValue <> 0 // This should not be possible, already taken care of by Codesys (?) THEN {IF defined (pou:SysMem.SysMemCpy)} SysMem.SysMemCpy(anyValue.pValue, _DataType.pValue, TO_UDINT(MIN(anyValue.diSize, _Descr.diSize))); {ELSE} // An ugly replacement MemCpy FOR I:=0 TO MIN(anyValue.diSize -1, _Descr.diSize - 1) DO anyValue.pValue[I] := _Descr.pValue[I]; END_FOR {END_IF} // Just to make sure, that our string is terminated... IF anyValue.TypeClass = TYPE_CLASS.TYPE_STRING THEN anyValue.pValue[anyValue.diSize -1] := 0; END_IF GET_Value := TRUE; RETURN; END_IF // ... But can play more CASE anyValue.TypeClass OF TYPE_CLASS.TYPE_WSTRING : ; // Could do conversion TYPE_CLASS.TYPE_XSTRING : ; // Wow, I have to figure this out TYPE_CLASS.TYPE_PARAMS : ; // BTW, what is this, how to use? TYPE_CLASS.TYPE_ANYNUM : ; // ... END_CASE Be careful it was not tested. I'm sure can be done better, please feel free to comment 3. If you really want to do entries with variable size In a standard environment, it would be similar to the previous, except you dont have the container variable _Data, just use a pointer, practically _Descr.pValue At Initialize (SET_Value), you have to allocate the memory, would be easy with SysMem.SysMemAlloc - nowadays with SysMem.SysMemAllocData -, and you make sure to release it after use with SysMem.SysMemFreeData... SysMemAlloc was already hidden. The problem with this, that sooner or later your application will totally fragment the dynamic memory, and fail... So should look for some form of dynMaybe MemUtils.MemoryManager (I am not sure what is the status and the future of it). 4. You will end up by a LogEntry Factory ... 5. You could still have a look at this IEC Snippets BTW, Standard Codesys Logger is not a bad choice either. If you are really interested, I share some more code / library.
Last updated: 2025-03-09

Sort by relevance or date