Delta RMC151 - Manual (Page 454)

RMC70/150 and RMCTools User Manual
packets from being delivered out-of-order or dropped.
10-11 01 01 FINS Command. These two bytes should be 01 01
to indicate a memory area read.
12-15 xx yy zz 00 FINS Address. This value encodes the register
address to read from the RMC. See the FINS
Address section below for details.
16-17 mm nn Read Length. This values holds the number of 16-bit
values to read. Notice that because the RMC uses 32-
bit registers, this value should be twice the number of
RMC registers to read. This value is encoded in binary
with the most-significant byte first. This value must
be less than or equal to 512.
The RMC will respond to this request with the following packet:
Offset Data
(hex)
Description
0-8 C0 00 02
00
00 00 00
00
00
Static Values. These 9 bytes will always have these
values in the response.
9 kk Service ID. This value will echo the Service ID in the
request. It should be used to match this response to
the corresponding request.
10-11 01 01 FINS Command. These two bytes will match the
command from the request.
12-13 rr ss Response Code. Indicates whether the read was
successful or not. See the FINS Response Codes
section below.
14... Data. The values of each register that was read will
follow the above header. Each 32-bit value will be
encoded as two 16-bit words, with the least-
significant word first, but with each individual 16-bit
word encoded with the most-significant byte first. For
example, the value 0x11223344 will be encoded as
33 44 11 22. Notice that many registers are in IEEE
floating point format, which can generally be cast to C
language float data values after correcting the byte
order to match your platform.
FINS Address
The FINS address field is a 4-byte field that instructs the read or write command as to
where in the RMC the data should be read or written. The first byte is called the Area
Code and selects which of three memory areas in the RMC to access. The next two bytes
are called the Starting Address, and indicates the offset from the start of the selected
memory area. Each memory area is limited to 32,768 sixteen-bit words. The fourth byte
indicates the bit address, but must be zero in requests with the RMC.
The starting point for determining the FINS Address is to look up the address as shown in
the FINS Addressing topic. A convenient tool is provided as well in the topic for converting
from an IEC address (e.g. %MD56.0) to a FINS Address. The address given by that topic
will be in the form of Dxxxxx or Ey_xxxxx. The prefix (D, E0_, or E1_) indicates the Area
Code to select, and the number following the prefix is the Starting Address. Use the
following chart to select an area code:
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