Mitsubishi MELSEC-A series, Programming Manual

Page: 262 / 508

7. APPLICATION INSTRUCTIONS
7
−
60
MELSEC-A
7.5.1 FIFO table write, read
(FIFW, FIFWP, FIFR, FIFRP)
Available Device
Bit device Word (16-bit) device Constant Pointer
Level
Ca
rr
y
fla
g
Err
o
r
fla
g
X Y M L S B F T C D W R A0 A1 Z V K H P I N
D
igit specification
Inde
x
M9012 (M9010, M9011)
(S) O O O O O O O O O O O O O O O O O O
FIFW
(D) O O O O O
(S) O O O O O O O O O O O O O O O
FIFR
(D) O O O O O
O O
Functions FIFW
(1) Performs the following actions:
1) Stores the data specified at (S) into the data table of FIFO table. The storage
position of data is as indicated below.
Data storage position = head address of data table + content of pointer
2) Adds 1 to the content of pointer. (For the pointer, use the device specified
at (D).)
(2) To use the FIFW instruction for the first time, clear the pointer specified at (D)
before executing the instruction.
Applicable
CPU
All CPUs
K1
to
K4
K1
to
K4
(3) To perform the management of the number of data which may be written to
multiple FIFO tables, use the user program.
Read commands
Indicates the instruction symbol.
(S)
•
Data to be written to
FIFO table or head
number of device
which stores data
•
Device number which
will store data read
(D)
Head device number of
FIFO table
Setting data
FIFW, FIFR
(S) (D)
(D) (S)
P
Pointer
The number of data stored in data
table is stored.
Head of FIFO
table
Device number of
destination
(D)+0
(D)+1
(D)+2
Data table
Data written by FIFW or FIFWP
in-struction is stored.