Siemens S7-300 Help!

[pasteleiro]

Hey

I come before you to ask your help about a problem I'm having with a program for S7-300.

Any ideas how to change the first bit of a word (or double word) to "1", then rotate it left until it reaches bit 15, then send that bit to another word, rotate, send and so on?

The idea is that the "1" goes through a series of words till it reaches a specific bit inside a specific word.

My questions: How do I adress a single bit inside a word? To write and read from it? How to rotate through a "n" number of words?


I'm new to Siemens so plz excuse me if I'm not seeing this right

Thank you all in advance

 

[L D[AR2P#0.0]]

Use the Help in the block editor, e.g.

 

[PeterW]

MD = 4 bytes, therefore MD4 = byte 4,5,6 and 7.

To set the left/right hand bits

A "ON" // Any true condition
= M 7.0 // Sets the most right hand bit
= M 4.7 // Sets the most left hand bit.

L MD4
SLD = shift all 32 bits left.



MW = 2 bytes, therefore Mw4 = byte 4 and 5.

To set the left/right hand bits

A "ON" // Any true condition
= M 5.0 // Sets the most right hand bit
= M 4.7 // Sets the most left hand bit.

L MW4
SLW = shift all 16 bits left.




Another note, CC 1 is set to 1 if the bit drops out at the end.

 

[pasteleiro]

thank you, i knew how to rotate and stuff, my problem was adressing the specific bits inside each dw or w

just another question..i know its possible to create an array of variables, in this case DW..is there anyway to rotate that array? if yes, how to do it?

ty all =D

MD = 4 bytes, therefore MD4 = byte 4,5,6 and 7.

To set the left/right hand bits

A "ON" // Any true condition
= M 7.0 // Sets the most right hand bit
= M 4.7 // Sets the most left hand bit.

L MD4
SLD = shift all 32 bits left.



MW = 2 bytes, therefore Mw4 = byte 4 and 5.

To set the left/right hand bits

A "ON" // Any true condition
= M 5.0 // Sets the most right hand bit
= M 4.7 // Sets the most left hand bit.

L MW4
SLW = shift all 16 bits left.




Another note, CC 1 is set to 1 if the bit drops out at the end.

 

[KalleOlsen]

You will have to make a load - transfer loop.
Here is a simple example:

 

[L D[AR2P#0.0]]

Here is a simple example:

...that shifts words, not bits.

 

[TurpoUrpo]

...that shifts words, not bits.

Kalle most likely answered to this:

thank you, i knew how to rotate and stuff, my problem was adressing the specific bits inside each dw or w

just another question..i know its possible to create an array of variables, in this case DW..is there anyway to rotate that array? if yes, how to do it?

ty all =D

 

[pasteleiro]

thank you all for your help, you guys are life savers

i'll be learning a bit more about PLCs and i hope in the future i can contribute more to the forum

cheers

J