It has become commonplace to monitor encoder feedback within a program in order to start a process based on actual position. The most reliable way to do this is to either tie directly into the lines of the encoder to get real-time encoder feedback. However, this method is not the most economical or readily available.
Similar results can be attained by using the multitasking abilities inherent to all ASEL, PSEL, SSEL, & XSEL controllers. An example of this would be to have one program controlling all the motion of the actuators and a second program running in parallel that is dedicated to monitoring the encoder data. While this method is not "true" real-time monitoring of the encoder, it does provide an extremely accurate feedback mechanism without physically attaching to the encoder.
Additional examples of dispensing are available,, but these examples do not perform any mid-move I/O toggle without stopping. This example demonstrates the ability for the ASEL, PSEL, SSEL, & XSEL to perform multiple tasks at the same time, in this case, the ability to toggle a dispense head based on position.
The following I/O has been chosen by the user:
- Output 303 : "On" = dispense on, "Off" = dispense off
- Output 304 : "On" = purge on, "Off" = purge off
- Input 10 : "On" = cycle start
- Input 12 : "On" = go to purge location
