Profibus-DP

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111 Appendix11.1 Profibus-DP network operationA Profibus-DP network uses a single EIA RS485 shielded twisted pair, and linksto nodes in a daisy chain type connection. All nodes are connected to thesame twisted pair, and network termination must be provided at each endof the network.The Object Dictionary must be set-up within the master PLC for each nodeon the network. This gives the node type, node address, number of datawords and data type for that particular node, and is usually set up using theGSD file supplied. Each node must then be configured to have a unique nodeaddress on the network.When communicating with a slave node, the master transmits theconfiguration data to it. This is the configuration data for that particularnode, as set-up in the Object Directory in the master PLC. The slavecompares this data with the its own internal set-up data. (NOTE: theconfiguration data is fixed internally for the Control Techniques Profibus-DPinterfaces.) If both sets of data match, the slave replies to the master PLCand enters data mode.Once the slave acknowledges that the configuration data is correct, themaster transmits the Request frame, consisting of a header, the OUT dataand a trailer. The OUT data consists of four 16 bit data words: 3 cyclic datachannels and 1 non-cyclic channel. The slave node will respond with a similarmessage, transmitting the IN data back to the PLC. The IN data format is alsofour 16 bit words, with 3 cyclic channels and 1 non-cyclic channel.Mapping information for each cyclic data channel is stored locally within theFLASH memory on the UD70, and is controlled by the UD70 operating system,IBSPROFI.SYS. This requires no addressing data to be sent by the controllingPLC, thus reducing the network transmission overheads.When data transmission is complete, the slave relinquishes control of thecomms line, and the master addresses the next node on the network. Onceall nodes have been addressed, OUT data transferred and IN data read, thecontroller has completed a network cycle. The IN data array is now availablewithin the PLC for re-calculating set-points for the process. Once all thesecalculations have been performed, the new set-points can be transferred tothe OUT data array. The network cycle can be run again, and new datatransferred to each node.11.2 Error detectionOnce data has been transmitted, the validity of the data is checked usingthe error code, which is also transmitted with the data words. If the data isvalid, then it is written to the destination parameter. Error correctioninformation is not transmitted, as data passing through the cyclic channelshas a very limited lifetime (1 network cycle), and error correction data wouldtake up additional network bandwidth. If the data is corrupted, it is nottransferred to the Drive.38Profibus–DPIssue code: pbnu2
12 Quick reference12.1 Set-up and mapping parametersFunctionUnidrive(Default)Mentor II(Default)Node Address #20.05 #14.01IN Channel 1 Mapping #20.07(Status word)#11.01(Status word)IN Channel 2 Mapping #20.03 (#2.01) #11.02 (#3.02)IN Channel 3 Mapping #20.04 (#4.02) #11.03 (#5.01)OUT Channel 1 Mapping #20.06(Control word)#11.04(Control word)OUT Channel 2 Mapping #20.01 (#1.21) #11.05 (#1.18)OUT Channel 3 Mapping #20.02 (#4.08) #11.06 (#4.08)12.2 General Drive functionsAction Unidrive Mentor IIActivate mappingchangesSave and activatemapping changesSet #MM.00 to 1070 andpress the RESET button.Set #17.19 to 1.Press RESET button whenthe Drive is disabled.Set #MM.00 to 1 and pressRESET.Remote Drive reset Set #10.38 to 100. Set bit 11 of the controlword to 1.Profibus–DPIssue code: pbnu2 39
Page 4: Contents1 Introduction 11.1 Using t
Page 8 and 9: 1.3 Mentor II - MD24The MD24 Profib
Page 11: 3 Electrical installation3.1 Profib
Page 14 and 15: 3.5 Network limitationsThe maximum
Page 16 and 17: 4.5 Network interruptionsIf a Unidr
Page 18 and 19: IN DataProfibus-DPMasterOUT DataNon
Page 20 and 21: 5.5 Mapping conflictsWhen the mappi
Page 22 and 23: 5.8 Saving Mentor II parametersTo i
Page 24 and 25: Example Mentor II control word valu
Page 26 and 27: Status word mappingUnidrive - UD73M
Page 28 and 29: 6.3 Reading parametersTelegram 1Tel
Page 30 and 31: Telegram 4The fourth telegram from
Page 32 and 33: Telegram 4The fourth telegram from
Page 34 and 35: 8 Diagnostics8.1 Determining if net
Page 36 and 37: 9 General information9.1 Option mod
Page 38 and 39: 9.5 System propagation delaysThe wo
Page 40 and 41: Unidrive 3 is the master Drive in t
Page 42 and 43: 10.3 OUT cyclic dataNode Device Cha
Page 46 and 47: 12.3 Control wordsUnidrive - UD73Me
Page 48: 42Profibus-DPIssue code: pbnu2

Profibus-DP

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