5.3
Registers
5-21
5.3 Registers
This section describes the types of registers used in MP2300 user programs (mainly ladder programs)
and how to use them.
5.3.1 Types of Registers
( 1 ) DWG Registers
Registers used by ladder programs (ladder drawings; DWG). Each drawing can use the registers out-
lined in the following table.

n: Decimal number; h: Hexadecimal number

B, W, L, F, and A: Data type (B: Bit, W: Integer, L: Double-length integer, F: Real number, A:
Address. Refer to 5.3.2 Data Types and Register Specifications on page 5-24.)
* Up to 32 D registers (32 words, DW0000 to DW0031) can be used when creating drawings, but
this can be changed in the MPE720 Drawings Properties Window. Refer to the Machine Controller
MP900/MP2000 Series User’s Manual MPE720 Software for Programming Device
(SIEPC88070005
îš…
) for details.
Type Name Specification Method Range Details Characteristics
S
System registers
SB, SW, SL, SFnnnnn
(SAnnnnn)
SW00000 to
SW08191
Registers provided by the system. SW00000 to
SW00049 are cleared to all zeros when the
system starts.
Common to all
drawings
M
Data registers
MB, MW, ML,
MFnnnnn
(MAnnnnn)
MW00000 to
MW65534
Registers shared by all drawings. Used, e.g., as
an interface between drawings.
I
Input registers
IB, IW, IL, IFhhhh
(IAhhhh)
IW0000 to
IW13FFF
Registers used for input data.
O
Output registers
OB, OW, OL, OFhhhh
(OAhhhh)
OW0000 to
OW13FFF
Registers used for output data.
C
Constants
registers
CB, CW, CL, CFnnnnn
(CAnnnnn)
CW00000 to
CW16383
Registers that can only be called from programs.
#
# registers
#B, #W, #L, #Fnnnnn
(#Annnnn)
#W00000 to
#W16383
Call-only registers Can be called only by
corresponding drawing. The usage range is set
by the user using MPE720.
Unique to each
drawing
D *
D registers
DB, DW, DL,
DFnnnnn
(DAnnnnn)
DW00000 to
DW16383
Internal registers unique to each drawing. Can be
used only by corresponding drawing.
The usage range is set by the user using MPE720.

S and M register data has a battery backup to ensure the data is held even if the MP2300 power is turned
OFF and ON. Other register data is saved to flash memory, so when the MP2300 power is turned OFF to
ON, data saved to flash memory is read and data not saved to flash memory is lost.
It is recommended, therefore, that data to be held regardless of whether or not the power is turned OFF to
ON should be written to M registers if possible.