HEIDENHAIN TNC 306 Technical Manual - Manual (Page 302)

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TNC 416/TNC 406/TNC 306 Program creation 3/2000
2 Program creation
The PLC program can be created directly on HEIDENHAIN contouring controls. For this purpose, the
PLC editor must be called with code number 807 667 (see Section "PLC-functions").
The PLC program can also be written with a special HEIDENHAIN compiler software (PLC.EXE).
2.1
Program structure
2.1.1 Command
A command is the smallest unit in a PLC-program. It consists of the operation and the operand.
A I 28 ;Comment
Operation
(A, AN...)
Operand
designation
(I, O, M, T, C,
B, W, D, K)
Operand
address;
constant value
Operand
The operation describes the function which is to be performed on the operand.
The operand indicates what is to be operated on. It consists of the operand abbreviation and a
parameter (address). Register and memory contents can be gated, erased and loaded by using PLC-
commands.
Both Bit- and Word-processing are possible. In Word-processing it is possible to address memory
contents with a length of 8 Bits (Byte), 16 Bits (Word) or 32 Bits (Double word) (see Section
"Commands").