Step Control - Run Options

Step Control Example

Run Options

This section on Run Options for the Step Control expands on the Simple Step Control example. If you have not completed this example then we recommend that you do complete it before continuing.

The Run signal for a Step Control can be set up in 4 different ways.

Field Switch OR Mimic Button with Manual Reset. Digital ON/OFF switch via a single digital MicroScan Input Tag. This option uses a single digital input either from a field switch or from a Mimic button.

If the digital input is OFF (=0), then the Step Control is stopped.
If the digital input changes from OFF (=0) to ON (=1) then the Step Control Starts.
When the Step Control finishes it will stay stopped even though the digital input is ON.
To restart the Step Control, first turn the digital input OFF, wait for it to be updated in the MicroScan Tool Box, then turn it back ON.
This setup is the same as the setup in the Simple Step Control.

Mimic Button with Auto Reset. This option uses both a digital input and a digital output to reset the signal and is designed for use with the Mimic. Generally an Input Tag and an Output Tag are setup to the same bit in the Image Interface. To start the Step Control, a button on the Mimic turns the bit ON. When the Step Control is finished the Step Master turns the bit OFF. To stop the Step Control before it has finished, the button on the Mimic is used to turn the bit OFF. To demonstrate this we will use the original Simple Step Control example. If you have modified the example then you could load the Template of it as a new TASK (remember to enable it).

Set the MicroScan Image Interface so that it runs with MicroScan.
Setup a MicroScan Input Tag and Output Tag to the same digital reference in the Image Interface for the Run signal.
Setup the MicroScan Mimic so that a button can turn the digital ON and OFF.
Add to the Mimic a digital object that shows the state of the digital Run signal.
Now in the MicroScan Tool Box Setup program edit ITEM 1 of the Step Control TASK - "Step Control ON/OFF" so that it is set to the new Input Tag which gets its Run signal from that digital reference in the Image Interface.
Now in the same TASK, edit ITEM 12 - "Step Control Master". Set property 8 - "Run Reset" to the Output Tag that references the same digital run signal in the Image Interface.
Now close the MicroScan Tool Box Setup program and run MicroScan. You should be able to start and stop the Step Control from the Mimic. Also when the Step Control has finished it should automatically reset the digital display on the Mimic to "stopped running".

Field Push Button with Auto Reset (via Digital Pulse Count). This Run signal is typically used with a device connected to the MicroScan Interface. The devices; IN2100-A16, IN2100-D and IN2100-A4 all support "Pulse Counting" on their digital inputs. Pulse Counting means that if a button is wired into one of the digital inputs, then every time the button is pushed, a register in the device will be increased by 1. When the value of the register is greater than 16,383 then the register is reset to 0 and the counting starts over. If this feature is used in conjunction with the ITEM Math_Toggle, then a very effective ON / OFF control can be achieved via a single push button in the field that is no longer dependant on the scan rate of the software monitoring it. Again to demonstrate this we will use the original Simple Step Control example. If you have modified the example then you could load the Template of it as a new TASK (remember to enable it).

Setup a MicroScan Analogue Input Tag from the "Pulse Count" register of a digital input on one of the above mentioned devices.
Now in the MicroScan Tool Box Setup program delete ITEM 1 of the Step Control TASK - "Step Control ON/OFF".
Add a new ITEM In_InputTag. Move this ITEM to the top of the list by clicking on the "Move Up" button. Set its properties as follows:

Class Name = In_InputTag
Name = Run Input
Enabled = Yes
Type = GetValue
Input Tag = select the MicroScan Input tag that was setup for the Pulse Count.

Add a new ITEM Math_Toggle. Now move this Item to the second top of the list, ITEM 2, by clicking on the "Move Up" button. Set its properties as follows:

Class Name = Math_Toggle
Name = Step Control ON/OFF
Enabled = Yes
Input Counter = Select the Run Input ITEM, ITEM1 which we have just set up.
Off if change to 0 = Select the Step Control Master ITEM, this should be ITEM 13. This enables the Auto Reset.
On PC Restart = Toggle Resume
Input Change Bit = None
Output Change Bit = None

Now in the same TASK, edit ITEM 13 - "Step Control Master". Set property 7 - "Run Input" to ITEM 2 "Step Control ON/OFF.
Now close the MicroScan Tool Box Setup program and run MicroScan. You should be able to start and stop the Step Control by pushing the field push button.

Field Push Button AND Mimic Button with Auto Reset. This Run option allows an operator to stop or start the Step Control from either a field wired push button or from a Mimic button. Generally a mimic button is set up as in 2. Above "Mimic Button with Auto Reset". The digital that is used by the Mimic button, for this option, is considered to be the Master Run Digital. The field push button is also configured, similar to 3. Above "Field Push Button with Auto Reset", but only insofar that it changes the state of the Master Run Digital whenever a change occurs. Please note that the value of the Math_Toggle is ignored in this configuration. To set up this configuration take the following steps:

Setup a MicroScan Analogue Input Tag from the "Pulse Count" register of a digital input on one of the devices mentioned in the above Run Option.
Setup the Run Option 2. Above "Mimic Button with Auto Reset".
Add a new ITEM In_InputTag. Move this ITEM to the top of the list by clicking on the "Move Up" button. Set its properties as follows:

Class Name = In_InputTag
Name = Field Run Input
Enabled = Yes
Type = GetValue
Input Tag = select the MicroScan Input tag that was setup for the Pulse Count.

Add a new ITEM Math_Toggle. Now move this Item to the second top of the list, ITEM 2, by clicking on the "Move Up" button. Set its properties as follows:

Class Name = Math_Toggle
Name = Step Control ON/OFF
Enabled = Yes
Input Counter = Select the Run Input ITEM, ITEM1 which we have just set up.
Off if change to 0 = leave this blank.
On PC Restart = Toggle Resume
Input Change Bit = Select the new Input Tag which gets its Run signal from that digital reference in the Image Interface.
Output Change Bit = Select the new Output Tag which sets the Run signal for the digital reference in the Image Interface.

Now close the MicroScan Tool Box Setup program and run MicroScan. You should be able to start and stop the Step Control by pushing the field push button and by pushing the Mimic button.

Notes

Where reference is made to a device that facilitates a "Pulse Count" function, please note that the same effect could be achieved by using a digital input with a simple switch. If a switch was to be used then the important thing to remember is that the CHANGE in state of the switch that is what is used. The switches actual position is ignored.

Refer to Step Master

Back to Items Index

Back to Contents