Using a Rotary Pulse Generator to Control Step Axis Structure

[ahend]

Greetings,

I have a step and direction pulse train from a rotary hand wheel that I want to intermittently use to control an axis. Using AXGEAR seams to be a solution but I'm confused setting up the master. If I connect the handwheel to a highspeed input configured as a high speed counter hitting on up pulses, that would handle the step control for the axis. How can I handle the high speed direction signal for that axis?

Is there a more elegant way to handle this? I'd like to just pass the high speed inputs directly to high speed outputs.   

Any advise appreciated!

[franji1]

Configure the High Speed Counter in the System Configuration dialog.  Click on the BRX Local I/O Entry in the tree on the left, then click on the High Speed I/O button on the main part of the dialog.  The top group are the Input Functions - pick one and configure it as a Counter.  That lets you "abstract" the direction mechanism so that the instruction "just works".

One of the options for the Counter behavior is "Bi-Directional Counter", then map the inputs for the count input signal and the direction signal.

I forgot, you can get to it from the AXGEAR box editor.  For the Master Register paramter, pick one of the <disabled> H/S C/T in the drop-down.  Then hit the red gear button to the right of the combo box.  Select the Counter tab and configure as described above.

[ahend]

Ok, the bi-directional counter setup is the trick - thanks, I give it a go.

Can I assume that the geared(slave) axis can still be independently controlled using other axis routines in the ladder logic?

[franji1]

Can I assume that the geared(slave) axis can still be independently controlled using other axis routines in the ladder logic?

Yes, but no.

When it's GEARING, the Axis is put in the electronic-gearing mode.  You must DISABLE the AXGEAR instruction if you want to do something else driving the slave axis outputs.  After the AXGEAR instruction is disabled, the Slave Axis will decelerate to 0, at which point in time the AXGEAR OnSuccess bit will turn ON and you can then do something else with the slave axis.

If you want to do something "on the fly", look at the AXSCRIPT instruction instead.  It has the capability to do multi-move/registration type behaviors.  Look at the Follow Master command.  There is a sample script you can look at from the AXSCRIPT instruction editor called Flying Saw.  I bet that is what you need.

*** EDIT *** Hit the Import button in the AXSCRIPT editor to import the Flying Saw script file.