The document discusses macros in CNC programming. A macro is a sequence of instructions stored and called as a single unit to perform repetitive tasks or operations on families of parts. Macros add flexibility over standard G-code programs by using variables and conditional statements. Common macro uses include calling canned cycles, setting families of parts, and controlling optional machines. The document describes different types of variables like local, global, and system variables that can be used in macros along with some common G and M codes.

1. MADE BY:- MEET SHAH
ENROLL. NO:- 156050319051
SUBJECT:- CAM
BRANCH:- MECHANICAL (SFI)
COLLEGE :- B&B INSTITUE OF TECHNOLOGY

2. What is macro?
Definition of macro.
Why use macro?
G and M codes.
Types of Variables .

3.  A sequence of instructions which are stored and
called up as one integral unit.
 Macro programming is useful tool for many cnc
machines.
 It provides a mean of shortening code and doing
repetitive tasks easily and quickly.
 Macro is also useful for families of parts.

4. A macro is a form of subprogram that
includes non G commands.
It is typically a common operation that will
be called many times.
Any program that performs a common
function and will be executed repeatedly
within a G code program.

5. A G-code program is rigid in structure and
can not be altered in mid-operation.
Offset are the only means to adjust the
machine path from one run to the next.
Macros add flexible with the use of
additional macro statements.
 With macros you can set up families of
parts, create custom canned cycles and
drive optional devices.

6. M01 Optional Program stop
M00 Program stop
M30 Program end and reset
G04 Dwell
G65 Macro sub program call
M97 Local sub program call
M98 Sub program call
M109 Interactive user input

7. Local variables
Global variables
System variables
String variables

8.  These variables are local to the program.
 They are used to transfer values to a cycle
call or as intermediate mathematical value
holders.
 They are reset to null when program is reset
or end.
 The local variables are typically #100-#499.

9. These variables once set remain set
unless you change or reset them.
Unlike local variables they are available in
any program.
It can be retained and used in any
program.
Global variable are typically #500-#999.

10. These variables are available to use in
macro programming and allow you to write
and retrieve information from control itself,
such as tool in spindle, tool offset active
etc.

11. It is group of characters interpreted as
single value.
Typically defined as $ symbol.
It allows you to manipulate text and
phases etc. `