IDEC MICROSmart FC5A Series, User Manual

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11: P
ROGRAM
B
RANCHING
I
NSTRUCTIONS
FC5A M
ICRO
S
MART
U
SER
’
S
M
ANUAL
FC9Y ‐ B1273 11 ‐ 5
DJNZ (Decrement Jump Non ‐ zero)
Applicable CPU Modules
Valid Devices
For the valid device address range, see pages 6 ‐ 1 and 6 ‐ 2
(
Basic Vol.).
Since the DJNZ instruction is executed in each scan while input is on, a pulse input from a SOTU or SOTD instruction should be used as
required.
The label number can be 0 through 127 (all ‐ in ‐ one CPU) or 0 through 255 (slim CPU). Make sure that a LABEL instruction of the label
number used for a DJNZ instruction is programmed. When designating S2 using a data register, the value for the label is a variable.
When using a variable for a label, make sure that all probable LABEL numbers are included in the user program. If a matching label
does not exist, a user program execution error will result, turning on special internal relay M8004 and the ERR LED on the CPU module.
FC5A ‐ C10R2/C/D FC5A ‐ C16R2/C/D FC5A ‐ C24R2/C/D FC5A ‐ D16RK1/RS1 FC5A ‐ D32K3/S3 FC5A ‐ D12K1E/S1E
X X X X X X
Device Function I Q M R T C D Constant Repeat
S1 (Source 1) Decrement value — — — — — — X — —
S2 (Source 2) Label number to jump to — — — — — — X
0 ‐ 127
0 ‐ 255
—
When input is on, the value stored in the data register designated by S1 is decremented
by one and is checked. If the resultant value is not 0, program execution jumps to
address with label 0 through 127 (all ‐ in ‐ one CPU) or 255 (slim CPU) designated by S2. If
the decrement results in 0, no jump takes place, and program execution proceeds with
the next instruction.
This instruction is available on upgraded CPU modules with system program version 210
or higher.
DJNZ S1
*****
S2
*****