Supported registers
This page lists the device families exposed by the Python high-level API. The exact range limits come from the selected canonical profile in PLC profiles.
Word device families
| Family |
Notation |
Example |
Notes |
DM |
Decimal |
DM0 |
General data memory. Start here for first reads. |
EM |
Decimal |
EM0 |
Extended data memory on KV-3000 and newer profiles except KV-NANO. |
FM |
Decimal |
FM0 |
File memory on KV-3000 and newer profiles except KV-NANO. |
ZF |
Decimal |
ZF0 |
File register area on KV-3000 and newer profiles except KV-NANO. |
W |
Hexadecimal |
W0 |
Link register word area. |
CM |
Decimal |
CM0 |
Control memory word area. |
TM |
Decimal |
TM0 |
Timer-related word area. |
VM |
Decimal |
VM0 |
Variable memory word area; not available on KV-X500 profiles. |
Bit device families
| Family |
Notation |
Example |
Notes |
R |
Decimal with two-digit bit |
R200 |
Relay bits. |
B |
Hexadecimal |
B0000 |
Link relay bits. |
MR |
Decimal with two-digit bit |
MR100 |
Internal relay bits. |
LR |
Decimal with two-digit bit |
LR100 |
Latch relay bits. |
CR |
Decimal with two-digit bit |
CR100 |
Control relay bits. |
VB |
Hexadecimal |
VB0 |
Variable memory bits; not available on KV-X500 profiles. |
X |
Decimal bank plus hex bit |
X10F |
Input alias in XYM profiles only. |
Y |
Decimal bank plus hex bit |
Y10F |
Output alias in XYM profiles only. |
M |
Decimal |
M0 |
Internal relay alias in XYM profiles only. |
L |
Decimal |
L0 |
Latch relay alias in XYM profiles only. |
Timer, counter, and index families
| Family |
Category |
Example |
Notes |
T |
Timer/counter |
T0 |
Timer status, current value, and preset helpers. |
C |
Timer/counter |
C0 |
Counter status, current value, and preset helpers. |
AT |
Timer/counter catalog category |
AT0 |
Digital trimmer; not available on KV-NANO or KV-X500 profiles. |
CTH |
Timer/counter catalog category |
CTH0 |
High-speed counter area on KV-NANO, KV-3000, and KV-5000 profiles only. |
CTC |
Timer/counter catalog category |
CTC0 |
High-speed counter area on KV-NANO, KV-3000, and KV-5000 profiles only. |
Z |
Index |
Z1 |
Index registers. KV-X500 profiles expose Z1 through Z10; other profiles expose Z1 through Z12. |
Type suffixes
| Form |
Example |
Meaning |
| Plain |
DM100 |
Default view for the device family. |
:U |
DM100:U |
Unsigned 16-bit word. |
:S |
DM100:S |
Signed 16-bit word. |
:D |
DM100:D |
Unsigned 32-bit double word. |
:L |
DM100:L |
Signed 32-bit double word. |
:F |
DM100:F |
IEEE 754 32-bit floating-point value. |
.n |
DM100.A |
Bit n inside a word, where n is hexadecimal 0 to F. |
:COMMENT |
DM100:COMMENT |
Device comment text through read_named. |
Addressing notes
| Symptom |
Rule |
X or Y is rejected. |
Use decimal-bank plus hex-bit notation, such as X10F. |
R, MR, LR, or CR is rejected. |
Use KEYENCE two-digit bit notation, such as R200 or MR100. |
AT, VM, VB, CTH, or CTC is rejected on KV-X500. |
Select the correct profile and check the range catalog before using model-specific areas. |
| A read works on one PLC but not another. |
The canonical profile controls the supported range table; see PLC profiles. |