MLX300 - Explanation of the Command Queue

The MLX300 is able to queue up 25 commands at a time.  These commands could be any Motion AOI or Robot Configuration AOI, such as a SetTool or SetUserFrame.    This document will explain the command queue tag structure and how to determine which command is executing.

Command Queue Tags

The MLX300 can execute a robot dance with 25 motion commands on the same rung.    When the rung is enabled, these motion AOIs will all be queue up before the first motion begins.   If there is an attempt to add more than 25 commands to the queue, a Max Buffer alarm will be shown on the HMI.

When a motion is added to the queue, it will use the next available index.   The picture below shows the  status of the 5^th command in the queue, which is currently executing.

Commands[4].InUse -           1 = a command is queued in this index

Commands[4].InEnabled -   1 = the command is executing

A watch window can be setup to view all the queue index locations.    The example below shows that there were 6 commands in the queue, and the first two have already executed.   The third command is currently executing.    The bottom tag show the Command Type of the AOI currently executing or if the controller is E-Stopped, it shows the last command that executed.

Command Type

The Command Type number in the tag shown above can be reference in the MLX300 Software manual, chapter 4.     If the controller has a lockup, lookup the last command type that was executing and search in the ladder for that command type to find where the alarm happened.

System Commands

The MLX300 system commands, like Abort, Hold and Reset do not get added to the queue.