Siemens SINUMERIK 840Di sl Programming Manual page 53

Block number
Main blocks are identified by a main block number. A main block number comprises the
character ":" and a positive whole number (block number). The block number always
appears at the start of a block.
Note
Main block numbers must be unique within a program to achieve an unambiguous result
when searching.
Example:
:10 D2 F200 S900 M3
Subblocks are identified by a subblock number. A subblock number comprises the character
"N" and a positive whole number (block number). The block number always appears at the
start of a block.
Example:
N20 G1 X14 Y35
N30 X20 Y40
Note
Subblock numbers must be unique within a program in order to achieve an unambiguous
result when searching.
The order of the block numbers is arbitrary, however increasing block numbers are
recommended. You can also program NC blocks without block numbers.
Addresses
Addresses are fixed or settable identifiers for axes (X, Y, etc.), spindle speed (S), feedrate
(F), circle radius (CR), etc.
Example:
N10 X100
Important addresses
Address
A=DC(...)
A=ACP(...)
A=ACN(...)
ADIS
B=DC(...)
B=ACP(...)
B=ACN(...)
Fundamentals
Programming Manual, 11/2006, 6FC5398-1BP10-2BA0
2.2 Language elements of the programming language
Meaning (default setting)
Rotary axis
Rounding clearance for path functions
Rotary axis
Fundamental Principles of NC Programming
Notes
variable
fixed
variable
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