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SCADA addresses of VM mapped values

Created by: InternationalTaxAnz at: 5/23/2022 10:02 PM (8 Replies)

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5/23/2022 10:02 PM	Rate (0)
InternationalTaxAnz Member Joined: 5/16/2022 Last visit: 6/16/2023 Posts: 5 Rating: (0)	Hi everyone! I recently started PLC programming and now i'm working with this amazing PLC. The programming itself is going good but now i need to expose some data coming from my Analog Inputs to the corporate SCADA. Let's say I have a PT1000 sensor in AI1 connected to an analog threshold trigger [B001]. The output of this trigger is mapped in my software as a Word with absolute(?) address VW4. Meanwhile the SCADA connection is managed through S7 drivers and in the LOGO I already set up the server connection with proper TSAP and it is working as expected. In fact i can easily read bits from digital inputs. What I'm not able to do is to reading the output value from VW4 that I VM mapped and I don't understand why. What physical address should I use in the SCADA tag to correctly "read" VM mapped values as in my scenario? Sorry for the newbie question and sorry if I was not clear in any part of the post but as I said I'm pretty new to this world Thanks in advance to everyone that will help me!

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5/24/2022 2:48 AM	Rate (1)
ixo65 Grandmaster-Expert Joined: 12/18/2014 Last visit: 12/1/2023 Posts: 31530 Rating: (3916)	There are no special "SCADA" addresses in the VM memory area. You can take any free address in the VM memory space. However, you should know how the memory area is structured so that there are no overlapping accesses. The memory area that can be used freely by the user is 851 bytes, byte 0 up to and including byte 850. The addressing is byte-oriented. Bit: Vx.y. x is the byte address, y is the bit address within byte x. Example: V0.0 Bytes: VBx. x is the address of the byte. A byte consists of 8 bits. Example: VB0 = V0.0 to V0.7 Word = VWx. A word consists of 2 bytes. Example: VW0 = VB0 + VB1 = V0.0 to V0.7 + V1.0 to V1.7. DWord = VDx. A DWord consists of 2 words. VD0 = VW0 + VW2 = VB0 + VB1 + VB2 + VB3 = V0.0 to V0.7 + V1.0 to V1.7 + V2.0 to V2.7 + V3.0 to V3.7. Attachment LOGO! Bit, Byte, Word and DWord.pdf (291 Downloads)

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This contribution was helpful to 1 thankful Users InternationalTaxAnz

5/24/2022 9:13 AM	Rate (0)
InternationalTaxAnz Member Joined: 5/16/2022 Last visit: 6/16/2023 Posts: 5 Rating: (0)	Hi ixo65, Thanks for your answer, I already read your PDF attached in some other topic around the forum and it is was very helpful! That's why I don't understand why I cannot see any output into my SCADA. Attached you will find a portion of the software I'm working on with Q1 that I used to verify the connection between SCADA and LOGO! that is linked in the SCADA with the I/O physical address Q0.0 For this and for what you wrote in your PDF I was expecting that the I/O physical address for my B002 was VW4 but it does not show anything. Attachment PT1000 sensor.zip (249 Downloads)

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5/24/2022 9:29 AM	Rate (0)
ixo65 Grandmaster-Expert Joined: 12/18/2014 Last visit: 12/1/2023 Posts: 31530 Rating: (3916)	In your program is all correct, no overlapping. You know that the value in VW4 is a integer (Int) value? What "SCADA" have you?

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5/24/2022 9:33 AM	Rate (0)
InternationalTaxAnz Member Joined: 5/16/2022 Last visit: 6/16/2023 Posts: 5 Rating: (0)	Correct me if I'm wrong: Should I be able to see any value of the Word that I mapped, exploring it bit by bit right? I mean "looking" in the bits from V4.0 to V4.7 and from V5.0 to V5.7, should I be able to see boolean values corresponding to the Word I mapped?

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5/24/2022 9:53 AM	Rate (0)
ixo65 Grandmaster-Expert Joined: 12/18/2014 Last visit: 12/1/2023 Posts: 31530 Rating: (3916)	In the Parameter-VM-Mapping, the "word" does not refer to the data format, but to the data width, namely 16 bits. Byte = 8 bits. Word = 16 bits. DWord = 32 bits.

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5/24/2022 11:17 AM	Rate (0)
InternationalTaxAnz Member Joined: 5/16/2022 Last visit: 6/16/2023 Posts: 5 Rating: (0)	Yes sure, it was clear. So I was expecting to "browse" the word mapped exploring it bit by bit from V5.0 to V4.7. Anyway I just solved the issue! The correct way to link the tag with my SCADA is with this address DB1.DBW4 Thank you for the support!

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5/24/2022 12:34 PM	Rate (0)
ixo65 Grandmaster-Expert Joined: 12/18/2014 Last visit: 12/1/2023 Posts: 31530 Rating: (3916)	InternationalTaxAnz Yes sure, it was clear. So I was expecting to "browse" the word mapped exploring it bit by bit from V5.0 to V4.7. Anyway I just solved the issue! The correct way to link the tag with my SCADA is with this address DB1.DBW4 Thank you for the support! I have ask you which SCADA but you didn't answer to this.

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5/24/2022 2:22 PM	Rate (0)
InternationalTaxAnz Member Joined: 5/16/2022 Last visit: 6/16/2023 Posts: 5 Rating: (0)	ixo65 InternationalTaxAnz Yes sure, it was clear. So I was expecting to "browse" the word mapped exploring it bit by bit from V5.0 to V4.7. Anyway I just solved the issue! The correct way to link the tag with my SCADA is with this address DB1.DBW4 Thank you for the support! I have ask you which SCADA but you didn't answer to this. You're right, sorry! Meanwhile we were discussing I found out how to properly access the memory. Anyway I'm using a Movicon Next 3.4 Thanks again for your support!

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