7 PROFIBUS DP Extensions
Bit Position
Byte
7 6 5 4 3 2 1 0
Designation
0
Structured_Length
1 Structure_Typ
2 Slot_Number
3 Reserved
4
:
243
User_Prm_Data
Figure 7-2 : Format of the Structured_Prm_Data block
Additional to the Set_Prm telegram (SAP 61) a Set_Ext_Prm (SAP 53)
telegram can be used for parameterization. This service is only available in
state WAIT-CFG after the reception of a Set_Prm telegram and before the
reception of a Chk_Cfg telegram. The new Set_Ext_Prm telegram simply
consists of Structured_Prm_Data blocks.
The new service uses the same buffer handling as described by Set_Prm.
By means of the New_Ext_Prm_Data interrupt the user can recognize
which kind of telegram is entered in the Parameter-Buffer. Additional the
SAP 53 must be activated by Set_Ext_Prm_Supported bit in Mode Register
0.
The Aux-Buffer for the Set_Ext_Prm is the same as the one for
Set_Prm and have to be different from the Chk_Cfg Aux-Buffer.
Furthermore the Spec_Prm_Buf_Mode in Mode Register 0 must not be
used together with SAP 53.
7.2 PROFIBUS DP-V1
7.2.1 Acyclic Communication Relationships
The VPC3+C supports acyclic communication as described in the DP-V1
specification. Therefore a memory area is required which contains all SAPs
needed for the communication. The user must do the initialization of this
area (SAP-List) in Offline state. Each entry in the SAP-List consists of 7
bytes. The pointer at address 17H contains the segment base address of
the first element of the SAP-List. The last element in the list is always
indicated with FFH. If the SAP-List shall not be used, the first entry must be
FFH, so the pointer at address 17H must point to a segment base address
location that contains FFH.
The new communication features are enabled with DPV1_Enable in the
Set_Prm telegram.
54 Revision 1.03
VPC3+C
User Manual
Copyright © profichip GmbH 2004-2006
To Next Page
Loading...