Schneider Electric VW3 A3 303 user manual Write Single Register

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8. Modbus protocol

8. 5. Write Single Register (6)

Request and response:

Slave no.

Word number

Value of word

CRC16

1 byte

2 bytes

Example: Write value 16#000D to logic address word 9001 (16#2329) on slave 2 (ACC = 13 s)

Request and response:

2329

000D

9270

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Contents Altivar Contents Before you begin Electric shock will result in death or serious injuryInstallation Manual Documentation structureProgramming Manual Communication Parameters ManualPresentation IntroductionNotation Hardware setup Installing the card in the driveReceipt Hardware descriptionChoosing polarization Switch codingCoding the address Address 1234Wiring recommendations Connecting to the busModbus RS485 standard Connection accessories Connection via RJ45 wiring systemConnection cables Connection cables for the master Type of master Master interface Description Catalog numberTWD XCA RJ030 TSX SCP CMConnection via junction boxes Description Catalog Number Subscriber socketRS485 double shielded twisted pair CablesTSX CSA500 TSX P ACCConfiguration Communication parametersControl Command Control via Modbus in I/O profileControl via Modbus or the terminals in I/O profile Parameter Value CommentControl via Modbus in Drivecom profile Control via Modbus or the terminals in Drivecom profileConfiguration Example of configuration via the graphic display terminal Communication scannerRDY NET COM. Scanner InputCommunication faults COM. Fault ManagementCONFIG. COMM. MAP Monitored parametersFormat Format Range Terminal displayDiagnostics Checking the addressLEDs Green RUN Red ERR Meaning Corrective actionRUN NET Communication MAPCOM. Scanner Input MAP COM Scan Output MAP CMD. Word ImageOutput variable Scanner parameter Input variable Scanner parameterCOM Scan Output MAP Communication fault Card faultPrinciple Modbus protocolSlave Slave j Slave k RTU mode Ascii modeModes Slave address Function code DataRead Holding/Input Registers 3/4 Modbus functions availableCode Modbus name Description Broadcast Size of data Write Single Register Diagnostics Get Comm Event Counter 11 = 16#0B Write Multiple Registers 16 = 16#10Read/Write Multiple Registers 23 = 16#17 Read Device Identification 43 = 16#2B MachineExample of positive response MEIInput variables Logic address Default assignment Output variables Logic address Default assignmentCode Modbus name Description Size of data Parameter Logic Read Input variable address Logic address Default valueParameter Logic Output control Parameter assignedInput monitoring Value Parameter assignedException responses Code Error codeResponse Read non-existent or protected parameters Logic address Parameter ValueAppendix RS485 standardModbus 2-wire standard schematic MasterModbus 4-wire standard schematic Uni-Telway schematic Wire Jbus schematic Type of trunk cable Cable with 1 shielded twisted pairDifferent scenarios Creating a Modbus bus using non-standard equipmentRecommendations Calculating the polarization ExampleRS485 schematic for the card Card connector pinoutContact no. Signal SUB-DAtv71ModbusJbusENV1 2005-05