Спецификация протокола Profibus

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b) FMA1/2 services:

- Reset FMA1/2

- Set Value FMA1/2

- Read Value FMA1/2

- Event FMA1/2

- SAP Activate FMA1/2

- RSAP Activate FMA1/2

- SAP Deactivate FMA1/2

The mapping of the DDLM functions to layer 2 and the associated Service Access

Points (SAP) are shown in table 45:

Table 45. Assignment of FDL parameters to the primitives

at master-slave communication

+-------------------------------+-----+-----+----------+---------+

!DDLM_Primitive !SSAP !DSAP !Layer 2 !Serv_ !

! ! ! !Service !class !

+-------------------------------+-----+-----+----------+---------+

! ! ! ! ! !

!DDLM_Data_Exchange.req/.ind !NIL !NIL ! SRD !high !

!DDLM_Data_Exchange.con ! ! ! !low/high !

!DDLM_Data_Exchange_Upd.req ! ! ! !low/high !

! ! ! ! ! !

!DDLM_Chk_Cfg.req/.ind !62 !62 ! SRD !high !

!DDLM_Chk_Cfg.con ! ! ! ! !

! ! ! ! ! !

!DDLM_Set_Prm.req/.ind !62 !61 ! SRD !high !

!DDLM_Set_Prm.con ! ! ! ! !

! ! ! ! ! !

!DDLM_Slave_Diag.req/.ind !62 !60 ! SRD !high !

!DDLM_Slave_Diag.con ! ! ! !low !

!DDLM_Slave_Diag_Upd.req ! ! ! !low !

! ! ! ! ! !

!DDLM_Get_Cfg.req !62 !59 ! SRD !high !

!DDLM_Get_Cfg.con ! ! ! !low !

!DDLM_Get_Cfg_Upd.req ! ! ! !low !

! ! ! ! ! !

!DDLM_Global_Control.req/.ind !62 !58 ! SDN !high !

! ! ! ! ! !

!DDLM_RD_Outp.req !62 !57 ! SRD !high !

!DDLM_RD_Outp.con ! ! ! !low !

!DDLM_RD_Outp_Upd.req ! ! ! !low !

! ! ! ! ! !

!DDLM_RD_Inp.req !62 !56 ! SRD !high !

!DDLM_RD_Inp.con ! ! ! !low !

!DDLM_RD_Inp_Upd.req ! ! ! !low !

! ! ! ! ! !

!DDLM_Set_Slave_Add.req/.ind !62 !55 ! SRD !high !

!DDLM_Set_Slave_Add.con ! ! ! ! !

! ! ! ! ! !

+-------------------------------+-----+-----+----------+---------+

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Table 46. Assignment of FDL parameters to the primitives

at master-master communication

+-------------------------------+-----+-----+----------+---------+

!DDLM_Primitive !SSAP !DSAP !Layer 2 !Serv_ !

! ! ! !Service !class !

+-------------------------------+-----+-----+----------+---------+

! ! ! ! ! !

!DDLM_xxx.req/.ind !54 !54 ! SRD !low !

!DDLM_xxx.con ! ! ! !low !

!DDLM_xxx_Upd.req ! ! ! !low !

! ! ! ! ! !

!DDLM_Act_Para_Brct.req/.ind !54 !54 ! SDN !low !

!DDLM_Act_Para_Brct.con ! ! ! ! !

! ! ! ! ! !

+-------------------------------+-----+-----+----------+---------+

The functions for master-master communication in the requester and also in the

responder operate all at the Service Access Point 54 (Master-Master-SAP).

12.3 Communication between DP-Master and DP-Slave

The communication between DP-Master and DP-Slave is described in figures 7 to 10

(see section "Master-Slave Communication").

If the DP-Master wants to communicate with a DP-Slave, the DP-Master requests

the Diag_Data of the DP-Slave, in order to check the readiness for operation of

the DP-Slave.

This function request (DDLM_Slave_Diag) will be repeated until the DP-Slave

responds with the requested data.

If the DP-Slave responds with the requested diagnostic information, the DP-

Master checks whether another DP-Master occupies this DP-Slave. If this is not

the case, the DP-Slave will be initialized and configured

(DDLM_Set_Prm/DDLM_Chk_Cfg).

Subsequently the DP-Master requests again the diagnostic data from the DP-Slave.

The following messages can occur:

a) parametrization and configuration error

b) The DP-Slave is occupied by another DP-Master

c) Static user diagnostics, so normal data transfer makes no sense

(for Example: external power supply for the outputs is missing)

d) DP-Slave is not ready for operation

In the cases a) and b) the DP-Master returns to the starting state and checks

again the readiness for operation of the DP-Slave.

In the cases c) and d) the DP-Master requests the diagnostic information from

the DP-Slave until the mentioned messages disappear.

If no error messages occur the DP-Master starts the user data exchange to the

DP-Slave. The input and output data will be transferred to and from the DP-

Slave. The DP-Master (class 1) indicates his own operation mode to the DP-Slaves

for the first time.

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FDL_DATA_REPLY.req

DDLM _Sla ve_Di ag.req

Responder (Slave)Requester (Master)

FMA1/2_SAP _ACT.req

SRD_REQ_PDU

DDLM_Slave_Init.req

FDL _DAT A_RE PLY. req

DDLM_Set_Prm.con (OK)

SRD_REQ_PDU

S RD_RES_P DU ( Low)

( No_Data)

( PRM_Data) (P RM_Data)

(NR)FDL_DATA_REPLY.con

D DLM_Set_P rm.re q

(PR M_D ata)

FDL_DATA_REPLY.ind

(P RM_Data)

D DLM_ Set_ Prm .i nd

(P RM_Data)

FMA1/2_Set_Value.req

(minTSDR)

FMA1/2_Set_Value.con

DDLM _Set_m inTSDR

(minTSDR)

R eal_Id ent = Exp_Iden t

FD L_DA TA_REPLY.req

DDLM _Ch g_Cfg .con (OK)

SRD_REQ_PDU

SRD_RES_PDU

(C fg_Data)

(Cfg_Data)

DDLM_Chk_Cfg.ind

FDL_DATA_REPLY.in d

(Cfg _D ata)

(C fg_Da ta)

(NR)

FDL_DATA_REPLY.con

( No_Data)

DDLM_Ch k_Cfg .req

(Cfg_ Data)

R eal_C fg = C fg_D ata

FM A1/2 _SAP_ ACT .req

(NIL, 56, 57, 58)

FM A1/2 _SAP _Act.con

DDLM_Enter.req

FDL_REPLY_UPD.req

FDL_REPLY_UPD.con

DDLM _RD_Outp_ Upd. req

DDLM_RD_Inp_Upd.req

DDLM_Data_Exchange.req

DD LM_S lave _ Diag.req

F MA1/ 2_SAP _AC T.con

(55,59,60,61,62)

FDL_R EPLY _UPD ATE.c on

FD L_REPLY_UPDA TE.c on

DDL M_Sl ave_D iag_ Upd.req

F DL_ REPLY_UP DATE.req

(D iag_Data)

FDL_REPLY_UPDATE.con

(Input_Data)

FDL_DATA_REPLY.ind

FDL_DATA_REPLY.req

(O utput_Dat a = 0)

FDL_DATA_REPLY.con

(Output_Data = 0)

(Output_Data =0)

SRD_REQ _PDU

S RD_R ES_P DU

( In p u t_Da ta)

(Ou tput_D ata = 0)

FDL_DATA_REPLY.req

D DLM_Slav e_Dia g.ind

FDL_DATA_REPLY.in d

FDL_REPLY_UPDATE.req

(Inpu t_Data)

DDL M_

Data_Exchang e_Up d.req

(Input_D ata)

FDL_DATA_REPLY.req

(Dia g_Dat a, Low )

FDL_DATA_REPLY.co n

DDLM _Slave_Diag.req

FDL_DATA_REPLY.ind

D DLM _Slav e_D iag. ind

SRD_REQ_PDU

SR D_RES_PD U (Low)

( Diag_Data)

SRD_REQ_PDU

S RD_R ES_P DU (Low)

( Diag_ Data)

D DLM _Get _Cfg_Upd.req

(C fg_Data)

FDL_REPLY_UPDATE.req

(Cf g_D a ta)

F DL_R EPLY_U PD ATE. con

D DLM_Slav e_Dia g.ind

(Diag_ Data, Low)

DD LM_Slave _Diag .req

FDL _DATA_REPLY.req

FD L_DATA_REPLY.con

SRD_REQ_PDU

SRD_RE S_P DU (L ow)

( D iag_D ata)

FDL_DATA_REPLY.ind

FDL_R EPL Y_UP DATE .req

(Diag_Data)

D DLM _Slav e_Dia g_Upd.req

(Station_Not_Ready = False)

D DLM _D ata _Exch ang e. ind

(Ou tput_Data = 0)

DD LM_S lave_ Diag.c on

(Diag_D ata, Low

Sta tion_Not_R eady = Tru e)

DD LM_S lave_Diag.con

(Dia g_Da ta, Lo w

Station_Not_R eady = Fals e)

(Input_Data)

DDLM_Data_Exchange.con

(S tation_Not _Read y = Tru e)

Slave not yet ready for operation

DD LM_Slave _Diag .con

(Diag _D ata, Low

Station_ Not_R eady = Tru e)

DD LM_D ata_Exchange.req

D DLM _Data _Exc hang e.ind

FD L_D ATA_REPL Y.ind

FDL_DATA_REPLY.req

(Output_Data)

FDL_DATA_REPLY.con

(Out put_D ata)

( Output_Da ta)

(Output_Data)

SRD_REQ _PDU

SRD_RES_PDU

( In pu t_D ata)

(O utpu t_D ata)

(Input_Data)

DDLM_Data_Exchange.con

DDLM_ Global_Control.req

FDL _DAT A.ind

FDL _DAT A.req

SDN_REQ_PDU

FDL_DATA _REP LY.con (N A)

DD LM_S lave_ Diag .con (NA )

FDL_DATA.con

DD LM_ Globa l_C ontrol. con

FD L_REPLY _UPD ATE.re q

(In put_D ata)

FD L_RE PLY_U PDA TE.c on

Store

Data

(In pu t_Data)

(Diag_Data, Low)

FDL_DATA_REPLY.con

User-Interface

DDLM FDL Bus FDL DDLM U ser-Interface

Store

Dia g_

Dat a

Store

Cfg_

Dat a

Stor e

Inp_

Data

Sto re

Diag _

Dat a

DD L M_ G lob al_Co nt rol .ind

DD LM _

Data _Exc hange _U pd .req

Figure 29. Sequence of the communication between DP-Master and DP-Slave

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12.4 Communication between DP-Master and DP-Master

The communication between DP-Master (class 2) and DP-Master (class 1) is handled

in a fixed way (see figure 30) with one exception.

This exception is the function DDLM_Act_Para_Brct, which is transferred as a

multicast from the DP-Master (class 2) to the corresponding DP-Master (class 1).

Communication is always initiated by the DP-Master (class 2). The DP-Master

(class 2) sends a request to the DP-Master (class 1) and waits for the response.

The service is processed by the DDLM of the DP-Master (class 2). After the

receipt of the response the DP-Master (class 2) can make a new request.

At one point of time the DP-Master (class 1) can only communicate with one DP-

Master (class 2).

The DP-Master communication is initiated by a DDLM_xxx.req (see also section

"DP-Master - DP-Master Functions") from the DP-Master (class 2). The DDLM passes

this request to layer 2 and checks the SRD_RES_PDU after receipt of the

response. If the response status is NR (no reply data) it will retry once more

with a new SRD with no L_sdu to get response data. This procedure will be

repeated by the DP-Master (class 2) until

- an erroneous SRD_RES_PDU

- or a SRD_RES_PDU with response data is received,

- or the watchdog T1 expires.

The result will then be passed to the User of the DP-Master (class 2) by means

of a corresponding DDLM_xxx.con.

The timer T1 will be started after receipt of the DDLM_xxx.req in the DDLM of

the DP-Master (class 2) and will be stopped after release of the DDLM_xxx.con.

The value loaded in the timer T1 depends on the FDL parameter and the

performance of the DP-Master (class 1).

The responder (DP-Master (class 1)) waits after a reset for a request. If the

DDLM of the DP-Master (class 1) receives a valid request, this request is passed

to the user by the corresponding DDLM_xxx.ind. At this point of time an access

protection was set to the local service access point (SAP) for the communication

with the DP-Master (class 2). This is necessary to make sure that the response

data will be sent to the right DP-Master (class 2).

After receipt of the response from the user (DDLM_xxx.res) the response data

will be passed with a FDL_REPLY_UPDATE.req to layer 2. Additionally, a timer

will be started which controls the request for the response. If this timer

expires and the response data are still not fetched by the DP-Master (class 2),

the DDLM deletes the response data because the DDLM presumes that the DP-Master

(class 2) is no longer available. In this case the access protection for the DP-

Master (class 2) will be cancelled. This will also be done in the case of a

single transaction if a FDL_DATA_REPLY.ind indicates that the response data are

fetched by the DP-Master (class 2). The value loaded in the timer of the DP-

Master (class 1) depends on the FDL parameter and the performance of the DP-

Master (class 2).

In case of master-master communication a sequence of requests can put into

parentheses. Therefore the access protection will be set by the "DDLM_Start_Seq"

and released by the "DDLM_End_Seq". To avoid errors the time between two

requests will be supervised. The value for the time supervision is added to the

DDLM_Start_Seq request. With the DDLM_Start_Seq.req the user can additionally

send an areacode. By means of this areacode at the beginning of a sequence an

area can be reserved at the user in the DP-Master (class 1).

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DDLM_Function.req

FDL_DATA_REPLY.ind

Responder (DP-Master (Class 1))Requester (DP-Master (Class 2))

FDL_DATA_REPLY.req

(Function.ind)

FDL_DATA_REPLY.con

(no Data)

(Function_REQ_PDU)

SRD_REQ_PDU

SRD_RES_PDU

( no Data)

(Function.res)

DDLM_Function.con

(Data)

Store

Data

FMA1/2_RSAP_ACT.req

(Access = All)

FMA1/2_RSAP_ACT.con

DDLM_Function.res

(Data)

FDL_REPLY_UPD.req

(Data)

FDL_REPLY_UPD.con

FMA1/2_RSAP_ACT.req

(Access = Rem_add)

FMA1/2_RSAP_ACT.con

DDLM_Function.ind

FDL_DATA_REPLY.ind

SRD_REQ_PDU

(no Data)

SRD_RES_PDU

(Function.res)

FDL_DATA_REPLY.req

(no Data)

FDL_DATA_REPLY.con

FDL_DATA_REPLY.req

(no Data)

FDL_DATA_REPLY.con

(no Data)

SRD_REQ_PDU

SRD_RES_PDU

(no Data)

(Function.req)

User DDLM FDL Bus FDL DDLM User

The following cycle will be repeated depending on

the time for reaction of the responder 0 ...n -times

Control time (T1) in the

DDLM of the Responder

for the Requester

Control time (T1) in the

DDLM at the Requester

Control time (T1) in the

DDLM of the Responder

for the User

Time for reaction

at the Responder

Figure 30. Sequence of communication between DP-Master (class˚2)

and DP-Master (class˚1)

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13 Formal Description of State Machines

13.1 General

The formal description is based upon a model. This model describes the DP

protocol with the help of state machines (represented by state diagrams). The

protocol sequences are described by different states (represented by ellipses

with the name of the state) and transitions between states (represented by lines

with arrows). State changes are caused by events (for Example time out) combined

with conditions. The state changes in turn lead to actions or reactions.

The formal description follows the description of the LLI state machines in the

PROFIBUS Specification. This description is based on an abstract model and it is

not the intention of the model to prescribe the translation in a concrete

realization.

13.2 Communication Model of DP-Master (Class 1)

13.2.1 General

The DP-Master (class 1) is subdivided in 4 instances:

1. layer 1/2, Subset of PROFIBUS (FDL and FMA1/2)

2. Direct-Data-Link-Mapper (DDLM)

3. User-Interface

4. User

An overview of the interactions between the individual instances is given in

figure 31.

13.2.2 FDL and FMA1/2

The layer 2 has to handle at least the FDL services SRD and SDN. In addition to

the services Reset FMA1/2 and Event FMA1/2 the service SAP Activate FMA1/2 is

also mandatory. To enable the communication with a DP-Master (class 2), it is

necessary to additionally implement the SRD-/SDN-responder functions and the

service RSAP Activate FMA1/2. In this case layer 2 must be able to handle SAP

access protection and Reply-Update-Mode = single.

Additional hints are given in the sections "Transmission Technology" and "Medium

Access and Transmission Protocol".

13.2.3 Direct-Data-Link-Mapper

The DDLM contains a mapping of the DDLM functions onto the layer 2 services.

For the DDLM of the DP-Master (class 1) the following local functions are

mandatory:

-DDLM_Master_Init

-DDLM_Responder_Init

-DDLM_Fault

-DDLM_Event

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Additionally the following data transmission functions are also mandatory:

-DDLM_Slave_Diag

-DDLM_Set_Prm

-DDLM_Chk_Cfg

-DDLM_Data_Exchange

-DDLM_Global_Control

With these functions the User-Interface carries out the data exchange with the

DP-Slaves.

In case of communication between a DP-Master (class 2) and a DP-Master (class 1)

the DDLM works transaction oriented. The DP-Master (class 1) can at one point of

time communicate with at most one DP-Master (class 2). It is not allowed to have

parallel services active.

The DP-Master (class 2) initiates these functions for the master-master

communication. It is not necessary for the DP-Master (class 1) to confirm these

functions with an immediate response. In this case the DP-Master (class 2) polls

the DP-Master (class 1) until the DP-Master (class 1) provides the response data

(see figure 30).

For the DDLM of the DP-Master (class 1) the following function is mandatory:

-DDLM_Get_Master_Diag

The DDLM provides optionally the following functions for the master- master

communication:

-DDLM_Start_Seq

-DDLM_End_Seq

-DDLM_Upload

-DDLM_Download

-DDLM_Act_Para_Brct

-DDLM_Act_Param

13.2.4 User-Interface

The User-Interface communicates with the DDLM using the functions as described

in the sections before.

The interface to the user is formed as a data and service interface. The

interface between user and User-Interface of the DP-Master (class 1) is

described in detail in section "DP-Master (class 1)".

The User-Interface consists of three function blocks:

- Slave-Handler

- Scheduler

- Service-Handler

The state machine of the Slave-Handler takes over the control of exactly one DP-

Slave. The management of each DP-Slave is made independently. The state machines

for each DP-Slave react individually depending on the state of the DP-Slave.

The DP-Slaves are processed following a fixed sequence. At each call the

corresponding Slave-Handler will make only one DDLM request. The Scheduler

determines the sequence of the calls of the corresponding Slave-Handlers (and

therefore the sequence of telegrams on the network). A given period of time

between two slave poll cycles has to be secured by the Scheduler. This period of

time (Min_Slave_Interval) is stored in the master parameter set. This time

depends on the performance of the used DP-Slaves in a given system.

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The Scheduler additionally has to initialize the DDLM and to reset the Slave-

Handlers at power up. Locally generated events and errors from FDL and DDLM are

evaluated by the Scheduler, too.

The Scheduler also controls the global state transitions:

- Offline:

The User-Interface carries out no actions, DDLM functions are

suspended.

- Stop:

The Slave-Handlers are locked, DDLM functions for master- master

communication (e. g. to load the parameters) are handled.

- Clear:

The Slave-Handlers are active, output data equal to zero are

transferred to the DP-Slaves.

- Operate:

The Slave-Handlers are active, the output data from the user are

transferred to the DP-Slaves.

The User-Interface takes over protective functions (Auto-Clear), if a DP-Slave

breaks down during operation. The Scheduler clears the outputs of the DP-Slaves

if the Error_Action_Flag is set and changes the operation mode to the state

"Clear". This change of the operation mode will not take place if the

Error_Action_Flag in the bus parameter set is not set.

The Mark function supports the user to handle the Sync and Freeze control

commands. This function gives the user the possibility to wait for a complete

slave poll cycle after which a defined transfer of input and output data can

take place.

The Service-Handler takes over the control for the local functions Load_Bus_Par,

Read_Value and Delete_SC.

13.2.5 User

The user represents the real application process of the corresponding device and

has to be defined depending on the application.

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Load_Bus_Par

User

DDLM

Local functions and Datatransfer-functions

FMA1/2

FDL

SDN

SRD

Slave_Dia

Set_Prm

Chk_Cf

Data_Exchan

Master-Parameterset

Bus-

Parameterset

Master-Master-

Functions:

Get_Master_Dia

Start_Seq

End_Seq

Upload

Download

Act_Param

Event

User-Interface

Input_

Data

Slave-

Parameterset

Set_Mode

Global_Control

Mode_Chan

Mark

Read_Value

Delet_SC

Master_Init

Global_Control

Reset

Responder_Init

Fault

Read_Value

Delete_SC

Start

Stop

Continue

USIF

Scheduler

USIF-STATE:

- Offline

- Stop

- Clear

- Operate

Service_

Handler

RESET, EVENT

RSAP ACTIVATE

SET VALUE

SAP ACTIVATE

READ VALUE

Act_Para_Brct

Set_Bus_Par

Output_

Data

Diagnostic_

Data

Slave_Handler

DEACT

UNLCK

DATA

PRM

CFG

DIAG2

DIAG1

Figure 31. Structure of a DP-Master (class 1)

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13.3 State Machines in the DP-Master (Master-Slave)

13.3.1 State Machine Slave-Handler

13.3.1.1 State Diagram Slave-Handler

WDATA

OK1

OK2

OK3

WPRM

WCFG

WDIAG2

EXD1

STOP

Power_On

DEACT

OK0

DIAG1

WDIAG1

PRM

CFG

DIAG2

DATA

UNLCK

WUNLCK

SUNLCK

WAIT1

WAIT2

INI1

WAIT3

INI2

STOP1

CONT1

NA0,RE0

DS0,LOCK

DEA0

DEA1

DEA2

DEA3

ERR0,DEA4,5

CONT2

STOP2

DS1

NA1,RE1

STOP3

CONT3

DS2

NA2,RE2

CONT4

STOP4

DS3,NA3,WT0

RE3,RJ0

CONT5,6,7

STOP5

DIAG1

DIAG2

RE4,5

STOP6

STOP7

CONT8

UNLCK2

UNLCK1

FATAL1

OK4,5 DS4,5

NA4,5

Figure 32. State Diagram of the Slave-Handler