CP340 or CP 341 communication processor

aprilchu

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• Sep 8, 2004

• #1

As i know , a communication processor and modbus frive can implement Modbus on CPU 314 .
Then what is a difference between CP341 serial communication processor and CP340 communication processor??

Thx.

 

fijo

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• Sep 9, 2004

• #2

CP 341 supports Modbus as Master and Slave, CP 340 does not.

 

aprilchu

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• Sep 9, 2004

• #3

still asking CP 314 and CP 340

Does it mean that CP341 can be a Master AND Slave at the same mod. ?

But, CP 340 just be either Master or Slave ?


Moreover, I found that Siemens has a product (6ES7 870-1AA01-0YA0).
Its description is Simatic S7, Modbus master v3.1 .
Does it mean that it just be a Master ???


Thx~~

 

fijo

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• Sep 9, 2004

• #4

Hi,

I mean CP 340 does not support Modbus at all.
CP 341 can be used as Master or Slave.
6ES7 870-1AA01-0YA0 - master driver
6ES7 870-1AB01-0YA0 - slave driver
- it also supports DF1

Does it surffice?

 

jasper007

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• Aug 9, 2015

• #5

Why CP340 don't need to write a read command？

HI!
I have a program made a serial port communication CP340 and peripheral equipment, discovery and DP different is that it does not need to send to READ instructions, called directly READ FROM CP340 can READ data, who can tell me why?

 

boneless

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• Aug 10, 2015

• #6

You might want to create a new thread. Piggybacking on a 11 year old thread seems a little bit silly.

While you are at it, try to elaborate your question. It does not make much sense to me.