Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 31

Number of steps (Macro type function blocks)
■ Calling source
When calling a macro type function block, the calling source loads the call-target program during compilation.
Program block 1 (displayed)
FB1_a
FB1
FB1_b
FB1
(1)
(1) The program is loaded in two or more call locations.
■ Program
The number of steps required for a function block program is the total number of instruction steps, like usual programs.
For the number of steps required for each instruction, refer to the following.
 MELSEC iQ-R Programming Manual (Instructions, Standard Functions/Function Blocks)
Number of steps (Subroutine type function blocks)
■ Calling source
When calling a subroutine type function block, the calling source generates the processing that passes the argument and
return value before and after the call processing.
Program block 1
(displayed)
FB1_a
M0 Y20
FB1
D0
FB1_b
M10
FB1 Y40
D10
The call-target program is
replaced with the call
instruction.
Program file
FB1 program
(FB1_a)
FB1 program
(FB1_b)
Program file
MOV D0 XX
M0
FBCall FB1_a
Y20
·
FB file
FB1 program
(1) Passing the argument
(2) Calling the FB1 program
(3) Passing the return value
(1)
(2)
(3)
Calling the
function block
3 PROGRAM ORGANIZATION UNITS
3.3 Function Blocks (FB)
3
29