ProSoft Technology MVI56-AFC - Manual (Page 127)

MVI56-AFC ♦ ControlLogix Platform Events
Liquid and Gas Flow Computer User Manual
ProSoft Technology, Inc. Page 127 of 316
February 25, 2011
9.5.2 Data Elements
Modbus Points
Point in
Modbus
Table
Mandatory or
Optional
Value Description
slave
selection
Mandatory P Primary Slave
V Virtual Slave
register
bank
Mandatory h holding registers
i input registers
register
address
Mandatory nnnnn
or,
+nnn A register address has
the form "nnnnn" which
is the 5-digit offset (0-
based) of the register in
the selected bank; a
register address may
also have the form
"+nnn" where "nnn" is
the 3-digit offset (0-
based) of the register in
a block of registers
which block is located
more globally by
accompanying text.
byte
selection
Optional L low-order byte
H high-order byte
bit number Optional /nn Bit number, if present, is
"/nn" where "nn" is the
number of the bit in the
16-bit register or 8-bit
byte, with bits numbered
from 0 at the low-order
end of the register or
byte.

"Ph00146" identifies the 16-bit register at offset 146 in the Primary Slave’s
holding register bank.

"Ph00006H/01" identifies bit 1 of the high-order byte of Primary Slave holding
register 6; this byte is already allocated in the AFC as the Site Extended
Status byte. This bit can be alternately addressed as "Ph00006/09", but the
AFC internally treats the two bytes as distinct.

"Ph00200/05" identifies bit 5 of Primary Slave holding register 200; this bit is
an as-yet unallocated bit in the Site Signals register.

"LDW+000" identifies the first of a block of registers in the Primary Slave
holding register bank and optionally in the Virtual Slave holding register bank,
which block’s absolute location is determined according to accompanying
text.