Siemens SPC3 Specifications download pdf (Page 7)

Introduction To ProfiBus DP

___________________________________________________________________

_______________________________________________________________________________________

Acromag, Inc. Tel:248-624-1541 Fax:248-624-9234 Email:sales@acromag.com http://www.acromag.com

The following state machine helps illustrates how ProfiBus DP operates

with respect to the slaves.

Note the four main states:

Power ON/Reset,

Parameterization, I/O

Configuration, and Data

Exchange.

The master uses the following

general telegram sequence

during startup:

1. Request Diagnostics.

2. Change Station Address

(optional service, Class 2

Master only).

3. Parameterize the Slaves.

4. Configure the Slaves.

5. Request Diagnostics

again before data

exchange to ensure that

system startup was OK.

6. Data exchange.

7. Global Control (optional).

Power ON/Reset State

The power on/reset state is the initial state following power up for the

DP slave. In this state, the slave may receive a telegram from a class 2

master to change its station address. A slave will be held in this state if it

does not have a valid address from 0-125. After completion of its power-on

initialization routine and if the slave has a valid station address, the slave will

proceed to the Wait for Parameterization state.

Parameterization State

In this state, the DP slave awaits the parameterization telegram from

the master which identifies the slave’s master and the mode the slave is to

operate in. A slave in this state will reject all other telegrams except a

request telegram for diagnostics or configuration. After its parameters have

been set, the slave will proceed to the I/O Configuration State.

I/O Configuration State

In this state, the slave awaits a configuration telegram that specifies the

number of input and output bytes that are to be exchanged in each data

telegram cycle with the slave. The configuration telegram also causes the

slave to check the configuration which was sent against the stored

configuration. A slave in this state will accept a request telegram for

diagnostics or configuration, or a set parameters telegram.

PROFIBUS DP SLAVE

STATE MACHINE

Data_Exch

Data Exchange

Valid Address

Set_Slave_Add

Slave_Diag

Get_Cfg

Chk_Cfg

Not OK

Set_Prm

Not OK

Chk_Cfg

Not OK

Data_Exch OK

Rd_Inp

Rd_Out

Slave_Diag

Chk_Cfg OK

Set_Prm OK

Get_Cfg

(GC commands:

Sync, Freeze, etc.)

Slave_Diag

Set_Prm OK

Get_Cfg

Invalid

Address

Chk_Cfg OK

Wait_Prm

Parameterization

ProfiBus DP Slave State Machine

Wait_Cfg

I/O Configuration

Power ON/Reset

1 2 3 4 5 6 7 8 9 10 11 12 ... 37 38

Comments to this Manuals

No comments

Siemens SPC3 Specifications Page 7

Comments to this Manuals

Related products and manuals for Networking Siemens SPC3