FX
/FX
/FX
Series Programmable Controllers
3G
3U
3UC
Programming Manual - Basic & Applied Instruction Edition
The table below shows the head device number in each sector:
Sector
Head device
number
number
Sector 0
R0
Sector 1
R2048
Sector 2
R4096
Sector 3
R6144
Sector 4
R8192
Sector 5
R10240
Sector 6
R12288
Sector 7
R14336
Operation (when a memory cassette is used)
• Extension registers (R)
[inside the built-in RAM]
Device number
S
S
+1
S
+2
S
+(2048×n)-1
Caution
1. Initialization of two or more sectors
When a memory cassette is attached, 18 ms is required to initialize one sector.
(When a memory cassette is not attached, only 1 ms or less is required to initialize one sector.)
When initializing two or more sectors, take either measure shown below.
• Set a large value to the watchdog timer D8000 using the following program
Initial pulse
M8002
Guideline of the watchdog timer set value
A value acquired by the following procedure can be regarded as the guideline of the watchdog timer set value.
If an acquired value is 200 ms or less, however, it is not necessary to change the watchdog timer set value.
1)
Write a program to be executed from GX Developer to the PLC.
[Online]→[Write to PLC...]
2)
Set the current value of D8000 (unit: ms) to "1000" using the device test function in GX Developer.
[Online]→[Debug]→[Device test...]→ "Word device/buffer memory" in Device test dialogbox
3)
Set the PLC mode to RUN, and execute the program. (Execute this instruction also.)
4)
Monitor the maximum scan time D8012 (unit: 0.1 ms) using the device batch monitoring function in GX Developer.
5)
Set the watchdog timer to the maximum scan time (D8012) or more.
D8012 stores the maximum scan time in increments of 0.1 ms.
Rough guide to the watchdog timer set value D8000 (unit: ms) is the "value stored in D8012 divided by 10" added
by 50 to 100.
Initialized device range
R0 to R2047,
ER0 to ER2047
R2048 to R4095,
ER2048 to ER4095
R4096 to R6143,
ER4096 to ER6143
R6144 to R8191,
ER6144 to ER8191
R8192 to R10239,
ER8192 to ER10239
R10240 to R12287,
ER10240 to ER12287
R12288 to R14335,
ER12288 to ER14335
R14336 to R16383,
ER14336 to ER16383
Current value
Before execution
After execution
H0010
HFFFF
H0020
HFFFF
H0011
HFFFF
HABCD
HFFFF
FNC 12
K
D8000
MOV
33 Extension File Register Control – FNC290 to FNC299
33.3 FNC292 – INITR / Initialize R and ER
Sector
Head device
number
number
Sector 8
R16384
Sector 9
R18432
Sector 10
R20480
Sector 11
R22528
Sector 12
R24576
Sector 13
R26624
Sector 14
R28672
Sector 15
R30720
• Extension file registers (ER)
[inside the memory cassette]
Device number
Before execution
H1234
S
H5678
S
+1
H90AB
S
+2
HCDEF
S
+(2048×n)-1
Initialized device range
R16384 to R18431,
ER16384 to ER18431
R18432 to R20479,
ER18432 to ER20479
R20480 to R22527,
ER20480 to ER22527
R22528 to R24575,
ER22528 to ER24575
R24576 to R26623,
ER24576 to ER26623
R26624 to R28671,
ER26624 to ER28671
R28672 to R30719,
ER28672 to ER30719
R30720 to R32767,
ER30720 to ER32767
Current value
After execution
HFFFF
HFFFF
HFFFF
HFFFF
725
31
32
33
34
35
36
37
38
A
B