1st bit of the status word.

NoName

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• Dec 21, 2003

• #1

Hello.

What I need is to transfer the first bit(it's the indicator that the position has been reached) of the status word 2 to an output bit so that I could use it elsewhere in the program.How could I achive this?

The second status word is located on PIW270 to 272 in the hardware manager.So basicly I would need only a PIW270.0, but the program doesn't allow that kind of addressing.

Thank you
>Ales<

 

Terry Woods

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• Dec 21, 2003

• #2

So... are you saying that status word is supposed to give positional status to the program? And that you can't READ that Status Word?

Is this "hardware manager" a motion control card?

If so, are you running it in Open-Loop?

 

paraffin power

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• Dec 21, 2003

• #3

Hi

L PIW270 //peripheral input word
T MW200 //scratch

A M201.0 //bit 0
= #what_you_want

 

NoName

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• Dec 21, 2003

• #4

Exactly what i want and need. I'll try this tomorow.Thank you for your help!!!

 

RRobbins

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• Dec 21, 2003

• #5

Terry the PIW you used and the MW you used is off by a byte. You would use m200.0 to match PIW270.0. Another way to do it, if you want just the LSB (Least Significant Bit) is needed, ignoring the rest.


L PIW270
L W#16#1 // IF MSB is needed change to 8000
AW // And Word
T MW270
NOP 0


L M 271.0 // for LSB or M270.7 for MSB
= Q 0.0 // What ever output

 

paraffin power

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• Dec 21, 2003

• #6

RRobins - it wasn't Terry - it was me; and I'm not off by a byte. The first bit is bit 0 which will be PIW271.0 i.e. M201.0

 

NoName

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• Dec 22, 2003

• #7

RRobbins said:

Terry the PIW you used and the MW you used is off by a byte. You would use m200.0 to match PIW270.0. Another way to do it, if you want just the LSB (Least Significant Bit) is needed, ignoring the rest.


L PIW270
L W#16#1 // IF MSB is needed change to 8000
AW // And Word
T MW270
NOP 0


L M 271.0 // for LSB or M270.7 for MSB
= Q 0.0 // What ever output

Click to expand...

When I try to load this, the PLC gives me an error msg.
And this line is red so I deleted it in my program and then loaded it to the plc.Is this the couse of the error???
L M 271.0 // for LSB or M270.7 for MSB

 

Bratt

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• Dec 22, 2003

• #8

Replace
L M271.0 With
A M271.0 Then Q0.0 will be 1 if M271.0 is 1.
If you write somthing that Step7 dosent approv of the syntax will be red and if you look at the lower left corner you will see the reason in this case you cant load a bit into accu 1 it has to be atlest a byte

 

NoName

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• Dec 22, 2003

• #9

I changed it to A M270. 1instead of M.And it still doens't work.Now the PLC gives me this error msg.
Event ID:16# 6539 Ilegal command in block (detected by compiler)

What could be wrong??

 

Bratt

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• Dec 22, 2003

• #10

What type of module/card are you trying to adress??? Is it a Profibus module???? It would be great if you posted a copy of the program.

 

RRobbins

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• Dec 22, 2003

• #11

Use an M word below 126. I didn't see where you said which PLC you were using. Some of the smaller S7-300's only use 0-126. Sorry.

 

NoName

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• Dec 22, 2003

• #12

I work in FBD by the way, So if I understand correctly this will then enable the output let's say q125.4 when the PIW270(first bit is 1) and W#16#1 are the same.Right???

 

RRobbins

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• Dec 22, 2003

• #13

I am assuming you are using the LSB or the right most bit. Type this in EXACTLY and you will be able to toggle FDB to STL and FDB and it will display in FDB.

A(
L IW270
L W#16#1
AW
T LW 0

SET
SAVE
CLR
A BR
)
A L 1.0
= Q 125.4

 

Bratt

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• Dec 22, 2003

• #14

I see no reason to filter this. The memorybyte is occupied by the instruction anyway. Just load the Peripihal inputbyte into a memorybyte. This way you can use the rest of the status bits in Pib270 aswell.

L PIB 271
T MB 100

A M100.0 (Pib271.0)
= Q125.4

When M100.0 (Pib271.0) turns 1 memorybit Q125.4 will be 1.

Or if you could adress the input directly

A I271.0
= Q125.4

This might also work

L PIB 271
T IB271

A I271.0
= Q125.4

Try and see its all depending on what card or module you are using if it is a profibus module/card then this might not be enough you then have to use Systemfunctions to transfer the Pib!

 

Last edited: Dec 22, 2003

NoName

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• Dec 22, 2003

• #15

RRobbins said:

I am assuming you are using the LSB or the right most bit. Type this in EXACTLY and you will be able to toggle FDB to STL and FDB and it will display in FDB.

A(
L IW270
L W#16#1
AW
T LW 0

SET
SAVE
CLR
A BR
)
A L 1.0
= Q 125.4

Click to expand...

This works just like I want it to work thank you very much RRobbins!!