Profibus mode: basic, Basic – Delta RMC151 User Manual
Page 520
RMC70/150 and RMCTools User Manual
Assume a value of 46.2 was written to %MD56.0 via PROFIBUS. The Event Log may
look like this:
Step 38 shows that the File is 56 (38 in hexadecimal), bit 31 is set to 1 for a write.
The Explicit Write register contains the write value 46.2, but it is very difficult to
decipher a float value from its hexadecimal representation.
Step 39 shows that the Read/Writer Request bit changed, which requested the
write.
6.9.5.3. PROFIBUS Mode: Basic+
The Basic+ mode is one of the Basic/Enhanced PROFIBUS Modes available only on the
RMC75P. Most users will prefer the I/O Modes instead.
Features
This mode has the following features:
•
Sixteen (16) user-selectable cyclic read registers are continuously read for instant
access by the PLC or PC.
See Response Block and Setting Up the Indirect Data Map below.
•
One (1) register anywhere in the RMC70 can be explicitly written or read.
See Read from the RMC70 and Write to the RMC70 below.
•
Commands can be issued to any number of axes simultaneously.
See Command Block, Issue a Single Command, and Issue Simultaneous
Commands below.
•
PROFIBUS bandwidth used: 16 consistent I/O words (16 bits each), plus 16 consistent
Input words (16 bits each).
RMC70 Register Addresses for PROFIBUS
When communicating over PROFIBUS, the RMC70 registers addresses use the same
file:element addresses as the RMC70 IEC-61131 addresses.
For example, to read the Axis 0 Actual Position via PROFIBUS, notice that its address is
%MD8.8. Therefore, the address via PROFIBUS is file 8, element 8.
Parameterization
Basic+ mode requires the PROFIBUS configuration and parameterization listed below. The
GSD file does direct the PROFIBUS master setup software to automatically set up these
values, but Delta has found several cases where it is not supported correctly or manual
setup is otherwise required.
Configuration: FF DF
Parameters:
Prm_Data (bytes 1-7): See the PROFIBUS DP specification for details.
User_Prm_Data (bytes 8-14): 00 00 00 xx* 00 10
* The xx parameter can be 00 or 01 and selects whether the least-significant word
comes first (00) or most-significant word comes first (01).
Data Blocks
500
Delta Computer Systems, Inc.