Спецификация протокола Profibus
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Page 451
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Requester . Slave/Receiver
.
.
User!FMS LLI FDL BUS FDL LLI FMS!User
=====!====!=============!======.======!=============!====!=====
! ! !\Buffer_free !
! ! !"generate !
! ! ! DTA_ACK_PDU !
! ! ![DTA_ACK_PDU]!
! ! ! !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! !<High>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! ! ! !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!--->] !
! [<------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]!\Buffer_free !
! REPLY.con) !*DTA_ACK_PDU ! !
! v ! !"generate !
!\Buffer_free ! ! DTA_ACK_PDU !
! ! ![DTA_ACK_PDU]!
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! !<High>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!--->] !
! [<------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]! !
! REPLY.con) !*DTA_ACK_PDU ! !
! v ! ! !
!\Buffer_free ! ! !
!\no outst. ! ! !
! LLI PDUs ! ! !
!"disable ! ! !
! Polling ! ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.con) ! ! !
! ! ! !
Figure 81. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with no Slave Initiative / parallel InformationReport
Services with high Priority / Receiver part
Page 452
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Requester . Slave/Receiver
.
.
User!FMS LLI FDL BUS FDL LLI FMS!User
=====!====!=============!======.======!=============!====!=====
INFO.req ! ! ! !
<#7,Low> ! ! ! !
----> ! ! ! !
[INFO_REQ_! ! ! !
PDU] ! ! ! !
DTA.req ! ! ! !
<#7,0, ! ! ! !
Low,INFO_! ! ! !
REQ_PDU>! ! ! !
---->![DTA_REQ_PDU]! ! !
!\no outst. ! ! !
! LLI PDUs ! ! !
!"enable ! ! !
! Polling ! ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.con) ! ! !
!(FDL_SEND_ ! ! !
! UPDATE.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !DTA.ind
INFO.req !(FDL_SEND_ !**INFO_REQ_ ! !<#8,0,
<#7,Low> ! UPDATE.con) ! PDU !(FDL_DATA_ ! Low,
----> ! !*DTA_REQ_PDU ! REPLY.ind ! INFO_
[INFO_REQ ! ![SRD_REQ_PDU]!<Low>) ! REQ_PDU>
PDU] ! ! ]------->!------------>!---->
DTA.req ! [<------!<-----------/! !
<#7,0,Low,!(FDL_CYC_DATA![SRD_RES_PDU]! ! INFO.ind
INFO_ ! REPLY.con) !*no Data ! ! <#8,Low>
REQ_PDU>! ! ! ! ---->
---->![DTA_REQ_PDU]! ! !
!(FDL_SEND_ ! ! !
! UPDATE.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !DTA.ind
!(FDL_SEND_ !**INFO_REQ_ ! !<#8,0,
! UPDATE.con) ! PDU !(FDL_DATA_ ! Low,
! !*DTA_REQ_PDU ! REPLY.ind ! INFO_
! ![SRD_REQ_PDU]!<Low>) ! REQ_PDU>
! ! ]------->!------------>!---->
! [<------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]! ! INFO.ind
! REPLY.con) !*no Data ! ! <#8,Low>
! ! ! ! ---->
! ! ! !
Figure 82. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with no Slave Initiative / parallel InformationReport
Services with low Priority / Request part
Page 453
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Requester . Slave/Receiver
.
.
User!FMS LLI FDL BUS FDL LLI FMS!User
=====!====!=============!======.======!=============!====!=====
! ! !\Buffer_free !
! ! !"generate !
! ! ! DTA_ACK_PDU !
! ! ![DTA_ACK_PDU]!
! ! ! !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! !<Low>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! ! ! !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!--->] !
! [<------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]!\Buffer_free !
! REPLY.con) !*DTA_ACK_PDU ! !
! v ! !"generate !
!\Buffer_free ! ! DTA_ACK_PDU !
! ! ![DTA_ACK_PDU]!
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! !<Low>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!--->] !
! [<------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]! !
! REPLY.con) !*DTA_ACK_PDU ! !
! v ! ! !
!\Buffer_free ! ! !
!\no outst. ! ! !
! LLI PDUs ! ! !
!"disable ! ! !
! Polling ! ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.con) ! ! !
! ! ! !
Figure 83. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with no Slave Initiative / parallel InformationReport
Services with low Priority / Receiver part
Page 454
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Remote FMA7 services:
Remote FMA7 services are mapped onto the LLI in the same way as the confirmed
FMS services. All FMA7 services are acknowledged by the user. The mapping of the
remote FMA7 services onto Layer 2 is described here for the example of the Read
Value Rem service. All other remote FMA7 services are mapped in the same way.
Read Value Rem service:
On a connection for Acyclic Data Transfer with no Slave Initiative the Read
Value Rem service is used for reading of variables or counters in a slave. FMA7
maps each read request (ReadValueRem.req) onto the LLI service primitive
DTC.req. The READ_VALUE-REM_REQ_PDU is transported with a SRD_REQ_PDU from the
master to the slave. The resulting FDL_DATA_REPLY.ind leads to a DTC.ind from
the LLI of the slave to FMA7. FMA7 maps the DTC.ind onto a ReadValueRem.ind to
the user.
The user of the slave passes the ReadValueRem.res to FMA7. FMA7 generates the
READ-VALUE-REM_RES_PDU and passes it with a DTC.res to LLI. LLI stores the READ-
VALUE-REM_RES_PDU in the low priority Layer 2 update memory
(FDL_REPLY_UPDATE.req <Low>). The following SRD_REQ_PDU causes the update memory
to be read.
The SRD_RES_PDU transports the READ-VALUE-REM_RES_PDU to the master. This leads
in the master to a DTC.con from LLI to FMA7 and then a ReadValueRem.con from
FMA7 to the user. If the user of the slave did not provide the data before a
SRD_REQ_PDU arrives, then the SRD_RES_PDU does not contain a READ-VALUE-
REM_RES_PDU and does not lead to a DTC.con to FMA7 (empty polling).
The following abbreviations are used in the figures below:
RV.xxx : ReadValueRem.xxx service primitive
RV_XXX_PDU : READ-VALUE-REM_XXX_PDU
Page 455
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Requester . Slave/Responder
.
.
User!FMA7 LLI FDL BUS FDL LLI FMS!FMA7
=====!====!=============!======.======!=============!====!=====
RV.req<#2>! ! ! !
----> ! ! ! !
[RV_REQ_ ! ! ! !
PDU] ! ! ! !
DTC.req! ! ! !
<#2,1, ! ! ! !
RV_REQ_ ! ! ! !
PDU> ![DTC_REQ_PDU]! ! !
---->!(FDL_SEND_ ! ! !
! UPDATE.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_SEND_ ! ! !
! UPDATE.con) ! ! !
!\no outst. ! ! !
! LLI PDUs ! ! !
!"enable ! ! !
! Polling ! ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.con) ! ! !
! ! ! !DTC.ind
! !**RV_REQ_PDU ! !<#1,1,
! !*DTC_REQ_PDU !(FDL_DATA_ ! RV_REQ
! ![SRD_REQ_PDU]! REPLY.ind) ! _PDU>
! ! ]------->!------------>!---->
! [<------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]! ! RV.ind
! _REPLY.con) !*no Data ! ! <#1>
! ! ! ! ----->
! ! ! !
Figure 84. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with no Slave Initiative / Mapping of the Read Value
Rem Service / Request part
Page 456
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Requester . Slave/Responder
.
.
User!FMA7 LLI FDL BUS FDL LLI FMS!FMA7
=====!====!=============!======.======!=============!====!=====
! ! ! !
! ! ! ! RV.res
! ! ! ! <#1>
! ! ! ! <----
! ! ! ![RV_RES_
! ! ! ! PDU]
! ! ! !DTC.res
! ! ! !<#1,1,RV_
! ! ! ! RES_PDU>
! ! ![DTC_RES_PDU]!<----
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! ! <Low>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!----->] !
<----!<------------!<-----------/! !
DTC.con !(FDL_CYC_DATA![SRD_RES_PDU]! !
<#2,1, ! _REPLY.con) !*DTC_RES_PDU ! !
RV_RES ! !**RV_RES_PDU ! !
_PDU> ! ! ! !
<---- ! ! ! !
RV.con<#2>! ! ! !
!\no outst. ! ! !
! LLI PDUs ! ! !
!"disable ! ! !
! Polling ! ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_CYC_POLL! ! !
! _ENTRY.con) ! ! !
! ! ! !
Figure 85. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with no Slave Initiative / Mapping of the Read Value
Rem Service / Response part
Page 457
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Connection for Acyclic Data Transfer with Slave Initiative (MSAC_SI)
On a connection for Acyclic Data Transfer with Slave Initiative the mapping of
all confirmed FMS services and of the unconfirmed FMS services (requester = mas-
ter) is analogous to the mapping for a connection for Acyclic Data Transfer with
no Slave Initiative (see data transfer definition).
The transmission of remote FMA7 services is not permitted on connections for
Acyclic Data Transfer with Slave Initiative.
The polling (CSRD) is started for this communication relationship
(FDL_CYC_POLL_ENTRY.req) during the connection establishment. The polling is
continued until an Abort releases the connection.
Unconfirmed FMS services with requester = slave:
Unconfirmed FMS services are services which are not acknowledged by the user.
For these services low or high priority may be used. The mapping of the uncon-
firmed FMS services onto Layer 2 is described here for the example of the Infor-
mationReport service. All other unconfirmed FMS services are mapped in the same
way.
InformationReport service:
On a connection for Acyclic Data Transfer with Slave Initiative the Information-
Report service is used for a single writing of data from a slave into a master.
The FMS maps each request (InformationReport.req) onto the LLI service primitive
DTA.req. The priority chosen by the user of the slave is transferred transpar-
ently. Corresponding to the priority, the LLI stores a DTA.req into the high or
low priority Layer 2 update memory. The following SRD_REQ_PDU causes the update
memory to be read. The SRD_RES_PDU transports the INFORMATION-REPORT_REQ_PDU to
the master. The resulting FDL confirmation leads to a DTA.ind from the LLI of
the master to FMS. FMS maps this DTA.ind onto a InformationReport.ind and passes
it to the user.
If there is memory available again (Buffer_free) for the LLI of the master to
receive another DTA_REQ_PDU, the LLI generates a DTA_ACK_PDU to signal this to
the LLI of the slave. Corresponding to the priority with which the DTA_REQ_PDU
was passed to LLI by the Layer 2, LLI maps the DTA_ACK_PDU either onto the Layer
2 service SRD with high priority or onto the Layer 2 service CSRD. The following
SRD_REQ_PDU transports the DTA_ACK_PDU to the LLI of the slave. This does not
lead to a confirmation to FMS.
Page 458
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Receiver . Slave/Requester
.
.
User!FMS LLI FDL BUS FDL LLI FMS!User
=====!====!=============!======.======!=============!====!=====
! ! ! ! INFO.req
! ! ! ! <#8,High>
! ! ! ! <-----
! ! ! !
! ! ! ![INFO_REQ_
! ! ! ! PDU]
! ! ! !DTA.req
! ! ! !<#8,0,
! ! ! ! High,
! ! ! ! INFO_
! ! ! ! REQ_PDU>
! ! ![DTA_REQ_PDU]!<----
! ! ! !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! ! <HIGH>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! ! ! !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!----->] !
! [<-------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]! !
! _REPLY.con) !*DTA_REQ_PDU ! !
! !**INFO_REQ_ ! !
<-----!<---] ! PDU ! !
DTA.ind ! ! ! !
<#7,0, ! ! ! !
High, ! ! ! !
INFO_ ! ! ! !
REQ_PDU>!\Buffer_free ! ! !
!"generate ! ! !
INFO.ind ! DTA_ACK_PDU ! ! !
<#7,High>! ! ! !
<---- ![DTA_ACK_PDU]! ! !
! ! ! !
!(FDL_DATA_ ! !(FDL_DATA_ !
! REPLY.req !*DTA_ACK_PDU ! REPLY.ind !
! <High>) ![SRD_REQ_PDU]!<High>) !
! ]------>!------------>!---->] !
! [<------!<-----------/! ! !
!(FDL_DATA_ ![SRD_RES_PDU]! v !
! REPLY.con) !*no Data !\Buffer_free !
! ! ! !
! ! ! !
Figure 86. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with Slave Initiative / InformationReport with high
Priority
Page 459
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
Master/Receiver . Slave/Requester
.
.
User!FMS LLI FDL BUS FDL LLI FMS!User
=====!====!=============!======.======!=============!====!=====
! ! ! ! INFO.req
! ! ! ! <#8,Low>
! ! ! ! <-----
! ! ! !
! ! ! ![INFO_REQ_
! ! ! ! PDU]
! ! ! !DTA.req
! ! ! !<#8,0,
! ! ! ! Low,
! ! ! ! INFO_
! ! ! ! REQ_PDU>
! ! ![DTA_REQ_PDU]!<----
! ! !(FDL_REPLY_ !
! ! ! UPDATE.req !
! ! ! <Low>) !
! ! (--!<------[ !
! ! (--!------>] !
! ! !(FDL_REPLY_ !
! ! ! UPDATE.con) !
! ! ! !
! !*no Data !(FDL_DATA_ !
! ![SRD_REQ_PDU]! REPLY.ind) !
! ! ]------->!----->] !
! [<-------!<-----------/! !
!(FDL_CYC_DATA![SRD_RES_PDU]! !
! _REPLY.con) !*DTA_REQ_PDU ! !
! !**INFO_REQ_ ! !
<----!<---[ ! PDU ! !
DTA.ind ! ! ! !
<#7,0, ! ! ! !
Low,INFO_! ! ! !
REQ_PDU> !\Buffer_free ! ! !
!"generate ! ! !
INFO.ind ! DTA_ACK_PDU ! ! !
<#7,Low> ! ! ! !
<---- ![DTA_ACK_PDU]! ! !
!(FDL_SEND_ ! ! !
! UPDATE.req) ! ! !
! ]------>!--) ! !
! [<------!--) ! !
!(FDL_SEND_ ! ! !
! UPDATE.con) ! !(FDL_DATA_ !
! !*DTA_ACK_PDU ! REPLY.ind !
! ![SRD_REQ_PDU]!<Low>) !
! ! ]------->!---->] !
! [<------!<-----------/! ! !
!(FDL_DATA_ ![SRD_RES_PDU]! v !
! REPLY.con) !*no Data !\Buffer_free !
! ! ! !
Figure 87. Master-Slave Communication Relationship / Connection for Acyclic
Data Transfer with Slave Initiative / InformationReport with low
Priority
Page 460
PROFIBUS-Specification-Normative-Parts-6:1997
Copyright by PNO 1997 - all rights reserved
6.3.4.3 Mapping of FMS/FMA7 Services onto Layer 2 for a Master-Master Communica-
tion Relationship
In this subclause the mapping of the FMS/FMA7 services onto the Layer 2 services
is described. A master - master communication in Layer 2 is assumed.
Connection for acyclic Data Transfer (MMAC)
Connections for Acyclic Data Transfer shall be established like all other con-
nection oriented communication relationships using a connection establishment
service (Initiate).
During the subsequent data transfer phase only the Layer 2 service SDA is used.
In this way parallel and mutual FMS services may be performed efficiently on the
same connection. All confirmed and unconfirmed FMS services and all remote FMA7
services are permitted on this connection. Multiple connections for Acyclic Data
Transfer may exist to a master at the same time. All these connections shall use
different LSAPs. Optionally the connection may be monitored (see data transfer
definition).
A connection for Acyclic Data Transfer is released with an Abort service (see
connection release definition).
Confirmed FMS services:
Confirmed services are services which are acknowledged by the user. The mapping
of the confirmed FMS services onto Layer 2 is described here for the example of
the Read service. All other confirmed FMS services are mapped in the same way.
Read service:
On a connection for Acyclic Data Transfer the Read service is used for reading
of data out of a master. The user marks each read request (Read.req) with a spe-
cial identification (Invoke ID). In this way it is possible to relate the sent
read request to the received read response. The FMS maps each read request onto
the LLI service primitive DTC.req. The READ_REQ_PDU is transmitted from the re-
quester to the responder with a low priority SDA_REQ_PDU. The resulting
FDL_DATA_ACK.ind leads to a DTC.ind from the LLI of the responder to FMS. FMS
maps the DTC.ind onto a Read.ind to the user.
When the user of the responder has passed the Read.res to FMS, FMS generates the
READ_RES_PDU and passes it with a DTC.res to LLI. LLI passes the READ_RES_PDU to
Layer 2 using a FDL_DATA_ACK.req <Low>. The resulting SDA_REQ_PDU transports the
data to the requester. The READ_RES_PDU is passed to LLI using a
FDL_DATA_ACK.ind. LLI passes it to FMS using a DTC.con. Then FMS passes the
Read.con to the user.