A.2
Special Registers
Just like the special relays (section A.1) starting at address M8000 the FX controllers also have
special or diagnostic registers, whose addresses start at D8000. Often there is also a direct con-
nection between the special relays and special registers. For example, special relay M8005
shows that the voltage of the PLC’s battery is too low, and the corresponding voltage value is
stored in special register D8005. The following tables shows a small selection of the available
special registers as examples.
Special registers can be divided in two groups:
–
Special registers whose value can only be read by the program
–
Special relays whose value can be read and written by the program.
The following tables feature a "Read" and a "Write" column. If the symbol "
쎲
" is shown in a one of
these columns, the corresponding action is possible. The symbol "—" means that the corre-
sponding action is not allowed.
A.2.1
PLC Status Diagnostic Information (D8000 to D8009)
Special Registers
Appendix
A - 6
MITSUBISHI ELECTRIC
Special Register
Read
Write
CPU
Function
D8000
쏹
쏹
FX
1S
FX
1N
FX
2N
FX
2NC
FX
3G
FX
3U
FX
3UC
Watchdog timer setting (in 1ms steps). (Writes from system
ROM at power ON) Value overwritten by program is valid
after END or WDT instruction execution. The setting must be
larger than the maximum scan time (stored in D8012).
Default value is 200 ms.
D8001
쏹
—
PLC type and system version
FX
1S
: 22V
VV
FX
1N
/FX
3G
: 26V
VV
FX
2N
/FX
2NC
/FX
3U
/FX
3UC
: 24V
VV
(e. g. FX
1N
Version 1.00
®
26100)
D8002
쏹
—
Memory capacity
0002
®
2k steps (FX
1S
only)
0004
®
4k steps (FX
2N
/FX
2NC
only)
0008
®
8k steps or more (not for FX
1S
)
If 16K steps or more "K8" is written to D8002 and "16", "32"
or "64" is written to D8102.
D8003
쏹
—
Memory typ:
00
H
®
RAM (Memory cassette)
01
H
®
EPROM (Memory cassette)
02
H
®
EEPROM (Memory cassette or flash memory)
0A
H
®
EEPROM (Memory cassette or flash memory,
write-protected)
10
H
®
Built-in memory in PLC
D8004
쏹
—
Error number (M)
If D8004 contains e.g. the value 8060, special relay M8060 is
set.
D8005
—
—
FX
2N
FX
2NC
FX
3G
FX
3U
FX
3UC
Battery voltage (Example: "36" -> 3.6 V)
D8006
—
—
Low battery voltage detection level.
Default settings:
FX
2N
/FX
2NC
: 3.0 V ("30")
FX
3G
/FX
3U
/FX
3UC
: 2.7 V ("27")
D8007
—
—
FX
2N
FX
2NC
FX
3U
FX
3UC
Momentary power failure count
Operation frequency of M8007 is stored. Cleared at
power-off.
D8008
—
—
FX
2N
FX
2NC
FX
3U
FX
3UC
Power failure detection
Default settings:
FX
2N
/FX
3U
: 10 ms (AC power supply)
FX
2NC
/FX
3UC
: 5 ms (DC power supply)
D8009
—
—
FX
2N
FX
2NC
FX
3G
FX
3U
FX
3UC
24V DC failed device
Minimum input device number of extension units and exten-
sion power units in which 24V DC has failed.
Summary of Contents for FX2N-32CAN
Page 1: ...MITSUBISHI ELECTRIC FACTORY AUTOMATION Programmable Logic Controllers GX IEC Developer ...
Page 2: ......
Page 4: ......
Page 6: ......
Page 10: ...IV MITSUBISHI ELECTRIC ...
Page 18: ...Modular PLC Training Hardware Course Overview and Requirements 1 2 MITSUBISHI ELECTRIC ...
Page 176: ...Device Edit 8 4 MITSUBISHI ELECTRIC ...
Page 190: ...Assigning DUT Variables to Function Blocks Data Unit Types DUT 10 10 MITSUBISHI ELECTRIC ...
Page 198: ...Array Example Single Dimension Array Arrays 11 8 MITSUBISHI ELECTRIC ...
Page 219: ...Sequential Function Chart SFC SFC Elements Training Manual GX IEC Developer 14 3 ...
Page 230: ...Structured Text Program Example IEC Structured Text 16 4 MITSUBISHI ELECTRIC ...
Page 278: ...PLC Components Glossary Appendix A 18 MITSUBISHI ELECTRIC ...
Page 283: ......