Delta RMC151 - Manual (Page 496)

RMC70/150 and RMCTools User Manual
In order to allow users to read and write registers in the RMC starting at locations other
than the beginning of a register file, the RMC defines four Custom Data Records, which
are addressed as Slot 0, Subslot 1, and Index 1000-1003:
Index Starting Address Description
1000 Configurable The starting address is configurable in
RMCTools.
1001 Configurable The starting address is configurable in
RMCTools.
1002 Configurable The starting address is configurable in
RMCTools.
1003 Configurable The starting address is configurable in
RMCTools.
The starting addresses of each of the Custom Data Records are set up in the PROFINET
Settings Page.
For example, to read or write a block of registers starting at variable 50 (%MD56.50), the
user can set Custom Data Record 1000 to have a starting address of %MD56.50, and
then read or write to Index 1000.
PROFINET-specific Record Data
In addition to the user data records described above, the RMC also supports PROFINET-
specific data records as defined in the PROFINET standard. These records are generally
only of interest to the PROFINET configuration software. They have Index values in the
range of 0x8000-0xFFFF. Refer to the PROFINET specification for details.
Record Data Format and Length
The contents of the Fixed and Custom Data Records match the contents of the
corresponding RMC registers. Therefore, each register will be a 32-bit (4-byte) DINT,
DWORD, or REAL data value. However, be aware that the MLEN and LEN parameters on
the RDREC and WRREC function blocks are in bytes. Therefore, these values must be 4x
the number of registers you want to read or write. By default each 32-bit value is
transmitted most-significant byte first, which should work for most IO controllers.
Otherwise, the byte order can be changed to least-significant byte first on the PROFINET
Settings Page.
The format and length of the PROFINET-specific data records are defined in the PROFINET
standard.
6.8.10.7.5. Handling Broken PROFINET Connections
It is important in many industrial applications to detect faults quickly. One such fault is losing
PROFINET I/O communication. PROFINET supports a configurable timeout value, which is
expressed in terms of a multiple of the update time. The default multiplier is 3 for most IO
Controllers. For example, for an update time of 16 ms and a timeout multiplier of 3, the
connection timeout will be 3 x 16 ms or 48 ms.
When either the IO-Controller or IO-Device does not receive a packet from the other device
for the timeout interval, it closes the connection and typically indicates this condition to the
main program. The method of indicating this condition depends on the actual device. This
topic describes the methods used by the RMC and STEP7.
Handling Broken I/O Connections in the RMC
The RMC has tags that indicate the state of the controlling connection. The user can use
these registers to qualify whether certain operations in the User Programs can be done,
or they can use these registers in the Program Triggers to respond to the change in state
476 Delta Computer Systems, Inc.