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Area length error when writing

Created by: Ayzetina at: 7/29/2013 8:41 PM (5 Replies)

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7/29/2013 8:41 PM	Rate (0)
Ayzetina Posts: 14 Rating: (0)	Hi dear experts. I need your experience on something, I'm working with a 319-3 PN/DP PLC and a CP341 RS485 MODBUS, but right now I'm having a problem with this PLC, it works normally, but after a while (the time is not constant, two, three, or maybe four hours) it stop the communication, and it send the next message on the Diagnostics buffer: Area length error when writing Global DB, double-word access, Access address: 180 Requested OB: Programming error OB (OB 121) Priority class: 1 And I don't really know why is this happening, because the program don't show exactly where is the problem. Can you help me with this??? Thanks and regards.
Ayzetina Posts: 14 Rating: (0)
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7/29/2013 10:12 PM	Rate (0)
yy1 Gold Member Joined: 3/24/2009 Last visit: 7/9/2024 Posts: 535 Rating: (112)	Dear Ayzetina, you can find the code, which causes the problem, when you check the call-stack. I guess, that you have an indirect DB-access, where the DB-adress gets over the size of the block. You should check if the requested DB is loaded to the CPU and the block has the required length (at least 184 byte) If the problem still persists you can post the code, which causes the stop. Best regards, yy1

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7/29/2013 10:21 PM	Rate (0)
Ayzetina Posts: 14 Rating: (0)	Hi, thanks for your answer, but I must say that I'm working with TIA PORTAL V11, do you know where can I find the call stack?? Thanks
Ayzetina Posts: 14 Rating: (0)
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7/30/2013 4:58 AM	Rate (0)
BhaPraJ Silver Member Joined: 1/28/2012 Last visit: 7/23/2024 Posts: 519 Rating: (83)	Ayzetina Hi dear experts.I need your experience on something, I'm working with a 319-3 PN/DP PLC and a CP341 RS485 MODBUS, but right now I'm having a problem with this PLC, it works normally, but after a while (the time is not constant, two, three, or maybe four hours) it stop the communication, and it send the next message on the Diagnostics buffer:Area length error when writingGlobal DB, double-word access, Access address: 180 Requested OB: Programming error OB (OB 121)Priority class: 1And I don't really know why is this happening, because the program don't show exactly where is the problem. Can you help me with this???Thanks and regards. Try to update your Program Global DB. .
	Regards, BhaPraJ
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7/30/2013 6:46 AM	Rate (0)
yy1 Gold Member Joined: 3/24/2009 Last visit: 7/9/2024 Posts: 535 Rating: (112)	Dear Ayzetina, in TIA Portal V11 you can use the "Open in editor"-button in the "Diagnostics buffer" window to open the block, which causes the stop. In this block you can use the monitoring function and have a look at the PLC registers and the call hierarchy. Best regards, yy1
	Last edited by: yy1 at: 7/30/2013 6:53 AM added call hierarchy
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7/30/2013 7:48 PM	Rate (0)
Ayzetina Posts: 14 Rating: (0)	Hi everyone, I've discovered something very interesting. My programm is just stopping my communication, but it didn't show any error on the diagnostic buffer, it just stops sending information, right now I'm working with Modbus telegrams, and I have an special record call (indice) which determinates the node from which the Modbus communication is asking for data. But somehow in some moment the counter just stops and there is no way that i can make it work again, I have to reinitiate the PLC, I really don't know what is wrong with this, any guess???
Ayzetina Posts: 14 Rating: (0)
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