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Communication between two S-300 cpu's over profibus
Created by: jweichler at: 3/21/2013 12:42 PM (7 Replies)
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| 3/21/2013 12:42 PM | |
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Posts: 25 Rating:
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Hi All I have 1 x s7-315F 2PN/DP cpu and 1 s7-315 2DP cpu. I am using step 7 5.5 I wish to transfer data between the two over profibus. I have installed a profibus cable with the termination resistors switch on at either end of the run. I have configured the 315F as the slave (address 2)and the 315 2DP as the master (address 4)in step 7. I have configured two bytes to transfer between the processors (see attached image) When I downloaded the hardware config to both cpu's they both displayed a fault and the diagnostic buffer was looking for OB82. I have added this block to both cpu's. The cpu's now run without a fault. If I turn one cpu off, the other recognises this and shows a BF However, I am unable to transfer data between them.I have written a simple program in STL which runs on the slave: L MB 100 //loads memory byte 100 T QB 102 //transfer to output byte 102 On the masterI run this program: L IB 103 //loadsinout byte 103 T MB 104 //transfer tomemory byte 104 I can watch the slavePLC and the valve of MB100 and QB102 is 0100_0000 (for example). However, the masterPLC just reads 0000_0000. Are the CPU's looking for OB82 because of an issue with my configuration? Any help here would be great. I have been referring to this guide written for Step 7 5.3 http://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&lang=en&objid=6518822&caller=view best regards John |
Last edited by: jweichler at: 3/21/2013 12:47 PMLast edited by: jweichler at: 3/21/2013 12:47 PMLast edited by: jweichler at: 3/21/2013 12:47 PM |
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| 3/21/2013 12:48 PM | |
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Posts: 25 Rating:
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slave hw config attached |
| 3/21/2013 12:48 PM | |
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Posts: 25 Rating:
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master hw config attached |
| 3/21/2013 12:53 PM | |
Joined: 3/21/2006 Last visit: 3/17/2025 Posts: 10239 Rating:
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Hello, Press F1 above marked OB82 for more info about needs of that block. Also therehttp://support.automation.siemens.com/WW/view/en/18458895 In both CPUs BF is OFF, isn't it? Best regards, Hristo Mihalev
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| 3/21/2013 1:02 PM | |
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Posts: 25 Rating:
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Thanks. I'll have a read. Yes, the BF led in both plc's is off. J |
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