ProSoft Technology PS69-DPS - Manual (Page 80)

Reference PS69-DPS ♦ CompactLogix or MicroLogix Platform
User Manual Profibus DP Slave Communication Module
Page 80 of 108 ProSoft Technology, Inc.
May 9, 2014
DPV1 Status Registers
The controller application program will use the DPV1 status registers as an
indication that the network Master has sent an unsolicited DPV1 Read/Write
request. The first will contain two bits which indicate if a read or write needs to be
processed. If this register contains a non-
zero value, the Slave’s user program
must create an appropriate response to this request by using a CIP MSG
command (shown in messaging section). The following table contains the
mapping of these registers.
Byte Offset Structure Member Data Type Data Type Description
32 RWInd SINT Read/Write
Indication A Read/Write Request has been received
33 RWIndCnt SINT Read Write
Indication Counter Increments on every new DPV1 request
34 MaAdr SINT Master Address Address of Requesting Master
35 Slot SINT Slot number Requested Slot Number
36 Index SINT Index Requested Index
37 DataLen SINT Date Length Requested Data Length
RWInd := DPV1 Read/Write Indication Status Bits
Bit Offset Structure Member Data Type Description
0 ReadReq BOOL 1 = Indicates a Read Request
1 WriteReq BOOL 1 = Indicates a Write Request
2 Reserved BOOL Reserved
3 Reserved BOOL Reserved
4 Reserved BOOL Reserved
5 Reserved BOOL Reserved
6 Reserved BOOL Reserved
7 Reserved BOOL Reserved
Note: Every DPV1 read or write request must be acknowledged by the PLC application program.
Otherwise the PROFIBUS master shuts down communication for both channels, V0 (cyclic IO
data) and V1 (non-cyclic messages). This can cause unexpected lost of data between the master
and the PS69-DPS slave.
Extended Status Information
Via the extended status area the Slave module is in the position to transfer 96
Byte extended status information to the controller application. The information
transferred depends on the parameter "ExtStaSelect" in the "Device Command
Register". This can be controlled by the application program. If the controller
application selects a specific extended status, it will be acknowledged by the
Slave module in the status region in "ExtStaSelect". If the slave adapter does not
acknowledge this selection, the extended information is invalid. The number of
bytes within the extended status area which are valid depends on the selected
status. The number of valid bytes will be shown in the status area in "ExtStaLen".