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Created by: Cimsengineer at: 6/3/2014 4:31 AM (4 Replies)

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6/3/2014 4:31 AM	Rate (0)
Cimsengineer Member Joined: 2/21/2014 Last visit: 10/10/2024 Posts: 2 Rating: (0)	all, I am using a db of 300 bool "lines" Can someone help me build a pointer to indirectly address say line 150?

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6/3/2014 4:53 AM	Rate (0)
hdhosseini Diamond Expert Joined: 1/28/2009 Last visit: 10/26/2024 Posts: 6852 Rating: (1365)	Cimsengineer all, I am using a db of 300 bool "lines" Can someone help me build a pointer to indirectly address say line 150? Good Morning World, Please, provide more information regarding type of controller you are using.Generally ,It is possible to make a solution in STL for S7-300/400.For STL,You need to formulate how line 150 related to physical address in DB.You need to know how build pointer for an specefic byte address and bit address and manipulate address registers. Hopefully,SCL for S7-300/400 provides more ease to access memory area with indirect addressing.For that,I think you should use array.(DB_Name.Name_of_array[i]) I hope these comments help you! Hamid Hosseini
	Last edited by: hdhosseini at: 6/3/2014 4:55 AM Demo Channel on Youtube
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6/3/2014 8:36 AM	Rate (0)
Jens_app Gold Member Joined: 1/5/2011 Last visit: 6/15/2024 Posts: 815 Rating: (123)	Cimsengineer all, I am using a db of 300 bool "lines" Can someone help me build a pointer to indirectly address say line 150? Dear Cimsengineer, like hdhosseini inquired it is useful for us to know what controller you are working with and what the intent of your program is. The reason for that is because there is more than one solution to your problem. For instance you can either use SCL or STLfor indirect addressing. In my eyes STL has greater possibilities for indirect addressing than SCL, but the SCL language is easier and faster the write anda must if you wantto address symbolic addresses and array components. Now before anyone contradicts this, I will give an example; for instance, try to indirect-address local variables with SCL, possible? I think not. While in STL you can, not advisable... but you can (greater possiblities). And now try to address a component in a array with STL, ok it is possible, you could point to the array and use the offset to access the components, but what if the datatype in your array changes and suddenly one component takes up a byte instead of a bit? You would have to adjust your code. While in SCL you could use an index to point to the component and it wouldn't matter if the datatypes changed, you would still be able to access that component. Ok, that's it for STL or SCL, conclusion; the choise is up to you and entirely application dependant. So my advice,tell us which controller you are using and what the intent of your program is, then we can offer better advice. Kind regards, Jens
	Keep it simple and on-topic. A simple straight-to-the-point answer is often of more quality than a complicated one.
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6/3/2014 1:32 PM	Rate (0)
Cimsengineer Member Joined: 2/21/2014 Last visit: 10/10/2024 Posts: 2 Rating: (0)	Thanks for your reply, I am using TIA with a 300 processor so all languages are available. The intent woult be to use a pointer that is built from an integer to examine a bit. For instance use the integer 17 to build a pointer to examine db36.dbx2.0

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6/3/2014 1:56 PM	Rate (0)
hdhosseini Diamond Expert Joined: 1/28/2009 Last visit: 10/26/2024 Posts: 6852 Rating: (1365)	Cimsengineer Thanks for your reply, I am using TIA with a 300 processor so all languages are available. The intent woult be to use a pointer that is built from an integer to examine a bit. For instance use the integer 17 to build a pointer to examine db36.dbx2.0 It is easier to develop a set code in SCL and reach to a result.In STL,it is possible but it requires higher level of programming to perform the task.As you can see in the followings, you have option of using a constant INT or a variable one #ty to access to a point in DB. If you still instersted to physical address, it is not difficult to find "dbx2.0" is referring to which cell inside an array. "Data_block_1".test[5]:= 1; "Data_block_1".test[#ty]:= 1; To compare both solutions, read 2nd discussion here: Selection of proper programming Language I hope this helps, Hamid Hosseini
	Last edited by: hdhosseini at: 6/3/2014 1:57 PM Demo Channel on Youtube
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