Tormach PCNC 770 - Other Input Codes; Feed Rate - F; Spindle Speed - S; Change Tool Number - T

Chapter 7
131
UM10350_PCNC770_Manual_0916A
Programming
7.8 Other Input Codes
7.8.1 Feed Rate – F
To set the feed rate, program: F~
Depending on the seng of the feed mode toggle, the rate may be in units-per-minute or units-per-
rev of the spindle. The units are those dened by the G20/G21 mode. The feed rate may somemes
be overridden as described in M48 and M49 above.
7.8.2 Spindle Speed – S
To set the speed in revoluons per minute (rpm) of the spindle, program: S~
The spindle turns at the commanded speed when it has been programmed to start turning. It is OK
to program an S word whether the spindle is turning or not. If the speed override switch is enabled
and not set at 100 percent, the speed is dierent from what is programmed. It is OK to program S0,
but the spindle does turn if that is done. It is an error if:
• The S number is negave
7.8.3 Change Tool Number – T
It is the programmer’s responsibility to ensure that the carriage is in a safe place for changing tools,
for example by using G30. This allows opmizaon of moon which can save me, especially with
gang tooling. A pause for manual intervenon can always be provided by an M00 or M01 before the
tool change. It is an error if:
• A negave T number is used or a T number larger than 54 is used
7.9 Advanced Programming with Parameters and Expressions
This secon describes the parameter and expression programming language features of PathPilot.
These features are not used in common G-code applicaon (hand coding), G-code created by
PathPilot conversaonal programming, or the majority of third-party CAM-programming systems.
NOTE: There are signicant dierences between controls in the way parameters work. Do not assume that
code from another control works in the same way with the operang system. Tormach advises against
wring parametric G-code as this is dicult to debug and very dicult for another operator to understand.
Modern CAM virtually eliminates the need for it.
7.9.1 Parameters
The RS274/NGC language supports parameters. Parameters are analogous to variables in other
programming languages. PathPilot maintains an array of 10,320 numerical parameters. Many of
them have specic uses. The parameters that are associated with xtures are persistent over me.
Other parameters are undened when the operang system is loaded. The parameters are preserved
when the interpreter is reset. Parameters 1 to 1000 can be used by the code of part-programs.