Siemens SINUMERIK 840D Operating Manual page 583

PLC variables
Inputs
Outputs
Bit memory
Times
Meters
Data
Formats
B
H
D
+/-D
F
A
Notation for variables
● PLC variables
● NC variables
Milling
Operating Manual, 03/2010, 6FC5398-7CP20-1BA0
Input bit (Ex), input byte (EBx), input word (EWx), input double word (EDx)
Output bit (Ax), output byte (ABx), output word (AWx), output double word
(ADx)
Memory bit (Mx), memory byte (MBx), memory word (MWx), memory
double word (MDx)
Time (Tx)
Counter (Cx)
Data block (DBx), data bit (DBXx), data byte (DBBx), data word (DBWx),
data double word (DBDx)
Binary
Hexadecimal
Decimal without sign
Decimal with sign
Floating point (for double words)
ASCII characters
EB2
A1.2
DB2.DBW2
– NC system variables - notation
$AA_IM[1]
– User variables/GUDs - notation
GUD/MyVariable[1,3]
– OPI - notation
/CHANNEL/PARAMETER/R[u1,2]
Alarms, error messages, and system alarms
20.4 PLC and NC variables
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