AH500 Programming Manual
2-4
Constant*
Decimal system K
16 bits: -32768~32767
32 bits: -2147483648~2147483647
Hexadecimal system 16#
16 bits: 16#0~16#FFFF
32 bits: 16#0~16#FFFFFFFF
Single-precision
floating-point number
F 32 bits: ±1.17549435
-38
~±3.40282347
+ 38
Double-precision
floating-point number
DF
64 bits: ±2.2250738585072014
-308
~
±1.7976931348623157
+ 308
*1: The decimal forms are notated by K in the device lists in chapters 5 and 6, whereas they are
entered directly in ISPSoft, for example, for K50, simply input 50.
*2: The floating-point numbers are notated by F/DF in the device lists in chapters 5 and, whereas
they are represented by decimal points in ISPSoft, for example, for F500, simply input 500.0.
*3: The strings are notated by “$” in chapters 5 and 6, whereas they are represented by “ ” in
ISPSoft, for example, for “1234”, simply input 1234.
2.1.2 Basic Structure of I/O Storages
Device Function
SM
OK - OK
-
SR
register
- OK OK
-
2.1.3 Relation between the PLC Action and the Device Type
Output relay
Power: OFF→ON
Cleared Retained Cleared
STOP
↓
RUN
The output relay is cleared.
The state of the output
relay is retained.
Retained Retained Retained
relay returns to that before
Retained Retained
relay returns to that before
the PLC’s stopping.
The non-latched area is
cleared.
Cleared Retained Cleared
The state of the latched
area is retained.
Retained Retained Retained