• Thread starter srinivasan soundararajan
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srinivasan soundararajan

Dear list,
Could anyone tell me the difference between profibus-DP & profibus-DPV1. I had one of my suppliers' catalogue stating their device supports profibus-DPV1.

Srinivasan Soundararajan
Engineer - Projects
Eurotherm Del India Ltd.

John Coppini

dpv1 is an extension of dp. dpv1 is acyclic; data transfers between master and slave have a specified format of the data (dp simply transfers unformated buffers).

also on the way is dpv2, which deals with motion control profiles.

Adrian Chesney

DPVI stands for DP version 1. There have been subsequent extensions since the specification was released. These extensions can be found in a single document by contacting your local
PROFIBUS office. Regards
Adrian Chesney The PROFIBUS GROUP (PNO UK)

Kai Atle Myrvang

This was a bit too simplified,

Classic DP is a cyclic protocol where all information has to be coded into the cyclic transfer, which can be as fast as once every mS.

Some clever guys found that this was a waste of bandwith for configuration and status telegram etc. So there was given space for one timeslot for each cycle where one acyclic telegram could be sent. This is used by PROFIBUS-PA.

BUT.....any classic DP master can read/write the cyclic data to/from a PA device (DP-V1 slave). They just cannot parameterize etc. the device.

One caveat....keep in mind that the PA instruments work with real float. IE the variable is presented as a mantissa and exponent.

Kai Atle Myrvang
PROFIBUS i Norge (PROFIBUS in Norway)