Using AUX inputs
Depending on the controller you are using it can have one or more AUX inputs. These inputs can be used in a number of ways:
- Normal digital inputs
- Monitoring input signals
Naming the AUX inputs
By giving each input a name it will become much easier in knowing what input is doing what. The inputs are shown in the I/O screen in the software.
In this case you see 'AUX1 IN' to 'AUX10 IN', depending on your controller more or fewer (or even no) inputs will be visible here. However, looking at these names it will be diffcult to remember what you are using each input for. Therefore, we have the option of naming the inputs. This is done in the CNC.INI file.
In the INI file you can go to the section 'IO', there you can find the names of the IOs:
Here you can rename the AUX input to reflect their function, for example, let's rename AUX2 input to 'Air in' and AUX6 input to 'Waterpressure'.
As a result on the I/O screen, you will now see their names appearing, making it easier to remember them.
Using AUX input as digital input in a macro
When used as digital inputs you can use these inputs eg. in a macro to check certain conditions and based on that decide on what to do. Reading an AUX input can be done with the G-code M56.
Reading the current state
M56 Px Read input x. result stored on #5399
M56 P3 (Read AUX in 3) If [#5399 == 1] Msg “AUX3=ON” Else Msg “A
Reading the current state and specify wait mode
M56 Px Ly Qy Read digital input and specify wait mode, result stored in #5399 Px: x is input number L0: do not wait L1: Wait for High L2: Wait for Low Qy: y is timeout
Below an example of this:
M56 P3 L2 Q30 (Read AUX in 3) If [#5399 == -1] Errmsg “Timeout while waiting for AUX3 becoming low” Else Msg “AUX3 is off” Endif
Using the AUX input for monitoring
Besides using the AUX inputs as digital inputs and using them in your custom macros, it is also possible to use them for adding extra safety by monitoring external values and based on that stop the machine or show a warning.
In the INI file in the section [SAFETY] you can find a number of entries called:
aux1InputCheckSenseLevel, aux2InputCheckSenseLevel, etc. With each line, you can specify for each AUX input what it should do when certain conditions are met. The image below shows the [SAFETY] part of the CNC.INI file:
The conditions you can specify are:
Value | Input condition | Action |
0,1,2 | No action | |
3 | On low | Stop |
4 | On high | Stop |
5 | On low | Slow feed |
6 | On high | Slow feed |
7 | On low | Warning |
8 | On high | Warning |
High and low indicate whether a high or low input signal will result in the indicated action.
Always check your controller's hardware manual to which signal levels (voltage) are allowed for the inputs signal.
The action that you specify, determines how that condition impacts the usage of the machine:
Action | Meaning | |
Stop | The machine will go to pause mode, and the machine can only continue when the input signal has been solved. | |
Slow | The machine will go to pause mode, but the operator can use the machine with 'slow feed' even when the input signal is not solved. | |
Warning | Warning, this will only cause a warning to appear. The machine can be used without any restrictions. | |
This monitoring is taken please even when a job is not (yet) running, this means depending on the action specified it can prevent you from starting a job (eg. stop condition), or have you run the job at a lower feed rate (slow feed condition).
A number of examples should help you in understanding how to use this feature for protecting your machine.
Example 1 - Stop on an input signal
In example 1, we will monitor the water pressure. We do this simply by modifying the appropriate line in the INI file:
- The 'IOGuard' indicates that a monitored input was triggered by turning red.
- A message is displayed, in this case, 'Water pressure active, please reset' with red background.
- The message is also displayed in the logging window in red.
- The machine has stopped, as can be seen by the 'Start' button turning green again.
As we have indicated that this condition results in a stop action, the only way to continue is to fix the problem (or reset the condition).
The term 'reset' means in this context, resetting the cause of this error. So this could be, for example, making sure that the water pressure is restored.
When the input condition is resolved the machine can continue by pressing the 'Start' button.
Please note, that if a stop condition is indicated, jogging will also not be possible.
Example 2 - Slow feed on an input signal
In example 2, we want to generate a 'slow feed' action on a high input signal. We do this by changing the appropriate line in the CNC.INI file.
- The 'IOGuard' indicates that a monitored input was triggered by turning red.
- A message is displayed, in this case, 'Water pressure active, please reset' with red background.
- The message is also displayed in the logging window in red.
- The machine has stopped, as can be seen by the 'Start' button turning green again.
The biggest difference with a stop condition is that in this case, it is possible to press the start button to continue. This will be indicated by the message 'RESUMED at low feed'.
Please note, that jogging is possible after this 'low feed' error has occurred, however, also jogging can be done only at a low feed.
Example 3 - Warning on an input signal
In example 3, we will only monitor the water pressure. We do this simply by modifying the appropriate line in the INI file:
This indicates that a high input signal on this input will show a warning.
When the machine is now running a job and this input is triggered a number of things will happen:
- The 'IOGuard' indicates that a monitored input was triggered by turning red.
- A message is displayed, in this case 'Waterpressure active, please reset'
- The message is also displayed in the logging window, please note that the background remains blue.
The term 'reset' means in this context, resetting the cause of this warning. So this could be, for example, making sure that the water pressure is restored.fd
It's also important to note that the execution of the job is continuing without interruption.