12 Automation lntegration
12.2 CNC Programming for Robotic Communication
170
M26
Transmit Low signal
H#
Specifies the input or output number. The default is H1.
The H code is used in conjunction with the Wait and Transmit codes.
Example -
Input
G25H3
This code tells the CNC machine to wait until the state at input #3 goes High.
Assuming the robot’s initial output state is Low, if this line of code is placed at the
beginning of the program, the CNC machine waits until input #3 goes High, then executes
the next line of code.
Example -
Output
M25H1
This code tells the CNC machine to output a High signal through output #1.
12.2.2.
G Code Programming for Input Signals
Both the G25 and G26 codes pause program operation until a signal change in the specified direction is
registered at the specified input. This is summarized in the table below.
Info Table: G Code Programming for Input Signals
Code
Function
If the signal is initially
Program will continue after
signal
G25
Wait for High signal
Low
changes to High
High
changes to Low and then
back to High
G26
Wait for Low signal
Low
changes to High and then
back to Low
High
changes to Low
Product Care
If the CNC machine does not respond to the robot as you have programmed it to, check that
you have wired the robot to the interface correctly and that the robot’s initial output state
was not changed to High while connecting the robot.
Take Note
In most cases the G commands can be omitted by using a VB script to send commands from
the robot to the CNC machine (for example, to open the door, open the clamping device,
etc.)
M commands used to send signals from the CNC machine to the robot cannot be replaced
by VB script.
