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Date and time. Again and again I think.

Created by: NewG at: 4/21/2009 5:51 PM (10 Replies)

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4/21/2009 5:51 PM	Rate (0)
NewG Posts: 5 Rating: (0)	Hello all. I have a block SFC1 in ladderand a DB30 block. (read system clock). CDT is pointing toa DATE AND TIME in DB30. Thats all thats in the DB block by the way. DATE AND TIMEhas left a space of 8 bytes below for year......etc So my question is how do I address each of the bytes in the DB30.Syntax.Ladder if that makes any odds. I amnot very new to this!!!. Just no good.... So go easy with me please... Geoff.
NewG Posts: 5 Rating: (0)
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4/21/2009 7:01 PM	Rate (0)
dchartier Grandmaster-Expert Joined: 9/27/2006 Last visit: 9/28/2023 Posts: 12153 Rating: (2624)	Hello Geoff; Here is a description of the Date and Time datatype format, and how it relates to your program: BYTE ContentsBCD Code Limits Address in your program 0 Year90-99h (19__) DB30.DBB0 00-89h (20__) 1 Month 01-12hDB30.DBB1 2 Day01-31h DB30.DBB2 3Hour 00-23h DB30.DBB3 4 Minute 00-59hDB30.DBB4 5 Second 00-59h DB30.DBB5 6 MSEC(high) 7 MSEC (low) 000-999h DB30.DBW6 8 Day of Week 1=Sunday DB30.DBB8 2=Monday ,,,,,,,, 7=Saturday Try opening a VAT table and looking at the addresses I have show above. Try to understand how the program fills the 8 bytes of the Date and Time variable once SFC1 has been called. You can then start using the different byte values in your program, in compare instructions for example. Hope this helps, Daniel Chartier
	Last edited by: dchartier at: 4/21/2009 7:03 PM
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4/21/2009 7:57 PM	Rate (0)
NewG Posts: 5 Rating: (0)	Ok Thanks. To explain further my problem:- Can you give a quick example of the address syntax for reaching those bytes on a compare block.What the actualline looks like that address those bytes in the table. Errrrr. How to do index addressingfor a DB.. I'm sure it's very simple but I don't know how towrite it.Something like P#db30[1..8]Byte??????. Geoff.
NewG Posts: 5 Rating: (0)
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4/21/2009 11:09 PM	Rate (0)
H-H Platinum Member Joined: 7/2/2008 Last visit: 9/27/2023 Posts: 928 Rating: (303)	dchartier You can then start using the different byte values in your program, in compare instructions for example. Hope this helps, Daniel Chartier As Mr. Daniel said, you can just use compare instructions. I don't know an SFC or SFB that compares date and time one shot. I hope someone knows better. I've attached an example where comparisons of individual bytes take place in OB1. You might just have faced a problem regarding type check of address. The comparison instructions in LADDER starts with INT comparisons where you have to compare word(size) by word(size) not byte with word or byte with byte. If you do so, you will have a message telling you Actual data type BYTE doesn't fit the formal type INT of the formal parameter. To overcome such a problem, you should do any of the following, 1- Write these simple lines in STL from the beginning. 2- In program editor go in Options>Customize>LAD/FBD and remove the check mark behind Type Check of Address (Check the PDF in zip file) I don't recommend to remove this check mark but if you don't want to write STL, just remove it and write your code in LADDER and when you finish testing your code check the box again and save, your code (comparisons part) will be automatically switched to STL. Best regards. H-H Attachment Date and time folder.zip (529 Downloads)

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4/22/2009 8:46 AM	Rate (0)
NewG Posts: 5 Rating: (0)	Ok thank you for that. I will take a look at the example later at work. Can you mix ladder and STL in a OB? Some networks STL while others are LADDER? I think in the distant past I haveused function blocks written in STL and used them in LADDER later. I don't get many S7 projects so I get very rusty on them. Geoff.
NewG Posts: 5 Rating: (0)
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4/22/2009 9:38 AM	Rate (0)
Ayman Elotaify Platinum Expert Joined: 5/28/2008 Last visit: 9/26/2023 Posts: 4477 Rating: (830)	Hello, Siemens hasmany functions that compares the content of two variables in the data type DATE_AND_TIME. Here's under these functions with short description for each one of them. Function FC9: EQ_DT The function FC9 compares the contents of two variables in the data type format DATE_AND_TIME to find out if they are equal and outputs the result of the comparison as a return value. Function FC12: GE_DT The function FC12 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is greater or equal to the other and outputs the result of the comparison as a return value. Function FC14: GT_DT The function FC14 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is greater than the other and outputs the result of the comparison as a return value. Function FC18: LE_DT The function FC18 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is smaller than or equal to the other and outputs the result of the comparison as a return value. Function FC23: LT_DT The function FC23 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is smaller than the other and outputs the result of the comparison as a return value. Function FC28: NE_DT The function FC28 compares the contents of two variables in the data type format DATE_AND_TIME to find out if they are unequal and outputs the result of the comparison as a return value. _____________________________________________________________________ And regarding to NewG's last question that if we can write a function / OB, some networks of it with LAD, and the other with STL? The answer is : YES. With best regards,
	Last edited by: Ayman Elotaify at: 4/22/2009 9:39 AM Ayman Elotaify
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This contribution was helpful to 1 thankful Users Borrina

5/24/2012 8:15 AM	Rate (0)
chin_ceptual Posts: 18 Rating: (0)	hi! this article was really very useful. Now i am able to fetch Date and time. I am having some queries. 1) why is it showing me Current Date 21 , Current Month - 04 and Year-1997. How can i sync it with the PC date & time? Adios
chin_ceptual Posts: 18 Rating: (0)
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5/24/2012 8:22 AM	Rate (0)
playerslight Posts: 1064 Rating: (72)	in program manager highlight your plc ,click on plc in tool bar ,click diagnostic and settings, click set time and date. in the new window that opens click apply
playerslight Posts: 1064 Rating: (72)	Last edited by: playerslight at: 5/24/2012 8:23 AM
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11/23/2013 2:33 AM	Rate (0)
BachTrans Posts: 10 Rating: (0)	Ayman Elotaify Hello, Siemens hasmany functions that compares the content of two variables in the data type DATE_AND_TIME. Here's under these functions with short description for each one of them. Function FC9: EQ_DT The function FC9 compares the contents of two variables in the data type format DATE_AND_TIME to find out if they are equal and outputs the result of the comparison as a return value. Function FC12: GE_DT The function FC12 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is greater or equal to the other and outputs the result of the comparison as a return value. Function FC14: GT_DT The function FC14 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is greater than the other and outputs the result of the comparison as a return value. Function FC18: LE_DT The function FC18 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is smaller than or equal to the other and outputs the result of the comparison as a return value. Function FC23: LT_DT The function FC23 compares the contents of two variables in the data type format DATE_AND_TIME to find out if one is smaller than the other and outputs the result of the comparison as a return value. Function FC28: NE_DT The function FC28 compares the contents of two variables in the data type format DATE_AND_TIME to find out if they are unequal and outputs the result of the comparison as a return value. _____________________________________________________________________ And regarding to NewG's last question that if we can write a function / OB, some networks of it with LAD, and the other with STL? The answer is : YES. With best regards, ----------------------------------------- Dear Ayman Elotaify, Can you show me how to use FC9, 12, 14, 18, 24, 28 to compare the time? Thank you, Bach
BachTrans Posts: 10 Rating: (0)
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8/29/2014 10:47 AM	Rate (0)
CS Moderator Moderator Joined: 9/1/2005 Last visit: 8/24/2023 Posts: 4102 Rating: (193)	new question published by boycementois split to a seperate thread with the subject Date and time - EQ_DT block. Best regards CS Moderator
	My Forum is the place to personalize your profile, track your topics, and maintain content that interests you. Best regards CS Moderator
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