Omron CX-PROGRAMMER V8.1, Operation Manual

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Function Block Applications Guidelines
Section 2-5
CP-series CPU Units
Note DM area of CP1L-L
If there is an instruction in the user program that accesses an address in an
FB instance area, the CX-Programmer will output an error in the following
cases.
• When a program check is performed by the user by selecting Program -
Compile from the Program Menu or Compile All Programs from the
PLC Menu.
• When attempting to write the program through online editing (writing is
not possible).
2-5 Function Block Applications Guidelines
This section provides guidelines for using function blocks with the CX-Pro-
grammer.
2-5-1 Deciding on Variable Data Types
Integer Data Types
(1, 2, or 4-word Data) Use the following data types when handling single numbers in 1, 2, or 4-word
units.
• INT and UINT
• DINT and DINT
• LINT and ULINT
Note Use signed integers if the numbers being used will fit in the range.
Word Data Types
(1, 2, or 4-word Data) Use the following data types when handling groups of data (non-numeric
data) in 1, 2, or 4-word units.
• WORD
• DWORD
• LWORD
Text String Data Use the following data type for text string data.
• STRING
Function block instance
area
Initial value of
start address
Initial value
of size
Allowed data areas
Non-retained H512 896 CIO, WR, HR, DM
(See note.)
Retained H1408 128 HR, DM (See note.)
Timer T3072 1024 TIM
Counter C3072 1024 CNT
Address CP1L-L
D0000 to D9999 Provided
D10000 to D31999 Not Provided
D32000 to D32767 Provided