SiePortal

The integrated platform for your product selection, buying and support workflow - bringing together Industry Mall and Online Support.

SiePortalDeutsch

Home
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menu temporary not available
- Menue temporary not available
- {{item.title}}

Products & Services
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Support Support
{{(apiData.Support | filter:{'rank':1}:true)[0].title}} Support
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
MySiePortal MySiePortal
{{(apiData.MySiePortal | filter:{'rank':1}:true)[0].title}} MySiePortal
- Menu temporary not available
- Menue temporary not available
- {{item.title}}
Cart ({{apiData.CartCount}})

Navigation

Request for Example of Variant Type in S7-1200 Programming

Created by: Captive Engineer at: 7/25/2011 10:59 PM (2 Replies)

Rating (0)

Thanks 0

3 Entries

7/25/2011 10:59 PM	Rate (0)
Captive Engineer Experienced Member Joined: 1/30/2006 Last visit: 1/8/2025 Posts: 104 Rating: (16)	Hello, TIA Portal experts and learners. Would anyone reading this be willing to show me an example of the use of the VARIANT data type supported by the S7-1200? According to the S7-1200 System Manual, "The data type Variant is can point to variables of different data types or parameters. The Variant pointer can point to structures and individual structural components. The Variant pointer does not occupy any space in memory." This description makes it sound a bit like a generic pointer, although that last bit about not occupying memory space sounds a bit unusual. It is unfortunate that no example is given in the manual. Regardless, since the data types POINTER and ANY seem to not be supported in the S7-1200 PLCs, the VARIANT type looks like the next plausible candidate. . . unless I've completely misunderstood the one paragraph that serves as the only description of this type. Interestingly, I find in programming that I can only declare VARIANT types on the INPUT and IN/OUT interfaces of function blocks. For functions, INPUT, IN/OUT, OUTPUT, and the Function's Return Value all support VARIANT declarations. I have found no such support in DBs, the PLC tags list, or the TEMP variable space provide in OBs. With these limits on using the VARIANT, I am looking for examples that help me understand the usefulness of having the VARIANT type. Chained to the PLC, The Captive Engineer

Suggestion To thank Quote Answer

7/26/2011 8:18 AM	Rate (0)
Cicero Gold Member Joined: 10/10/2005 Last visit: 1/29/2025 Posts: 1940 Rating: (138)	Hello Captive Engineer, regarding to your inquiry in refer to the example of VARIANT data type or example for the indirect addressing methode please find enclosed the example programs, which are created in STEP 7 V10.5. These FAQs should be also apply in STEP 7 TIA Portal V11. http://support.automation.siemens.com/WW/view/en/42603286 http://support.automation.siemens.com/WW/view/en/42603882 With best regards Cicero

Suggestion To thank Quote Answer

7/26/2011 5:02 PM	Rate (0)
Captive Engineer Experienced Member Joined: 1/30/2006 Last visit: 1/8/2025 Posts: 104 Rating: (16)	Cicero, Thank you for the examples you posted. The first example is of particular interest as it demonstrates that it is possible to use the non-symbolic ANY type notation to feed a VARIANT parameter. This notation allows me to select a certain size of data to be sent in the TSEND_C FB (good). However, since there does not appear to be a variable container for the ANY data type,I cannot adjust the data size nor can I change the area to which I want to point at runtime with this method (not so good). I wonder if it would be possible to create a UDT that could mimic the ANY data type. . . Perhaps I shall follow up with the results of that experiment. By the way, since I am utilizing TIA Portal V11, the option for deselecting "symbolic addressing only" is not available by that nomenclature. I mention it since the first example provided was created using V10.5. Kind regards, The Captive Engineer

Suggestion To thank Quote Answer

Share this page:

Share this page on...

SiePortal

Request for Example of Variant Type in S7-1200 Programming

Created by: Captive Engineer at: 7/25/2011 10:59 PM (2 Replies)

Rating (0) Thanks 0

3 Entries

Captive Engineer

Cicero

Captive Engineer

3 Entries

Follow us on

Rating (0)

Thanks 0