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DRO with VFD Project

While converting my Bridgeport to EMC, I still needed to be able to use my mill manually. Rather than reconnecting the existing DRO and spindle power switch, I decided to setup an EMC DRO and spindle controller based on the information here:http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?PyVCP

Here, are the files I developed for my system using the existing linear scales and a Pico Systems UPC servo controller with the DAC option.

Here is a screenshot of my current version. I was surprised with how well it works. The DRO fills my entire screen so the position numbers and buttons are very large. Once I have clicked on the Speed Adjust box, from that point on, all I need to do is use the Up and Down arrow keys on my keyboard to change speed.

I haven't tried this one yet. If this works, I should be able to use one XYZ set to keep track of a home position, and then zero the other set any time I need to do an incremental move.

If you have a machine with a DRO on it already, it should be easy to replace the display with an EMC DRO and PC with a printer port. X, Y and Z encoders would take up six input pins, making the remaining pins available for others things. I am working on building a DAC board that can run on three output pins, plus two more for optocoupler outputs. This can be used to run a spindle VFD analog input, Forward and Reverse. Solid state relays could be added to output pins to run mist, coolant or other things. Remaining printer port inputs could be used for real buttons. Real spindle forward and reverse buttons would be nice to have for tapping and collet changes. EMC can handle up to eight printer ports and PCI cards are cheap.

I tested the dual readout version and it works fine. I tried to rearrange features to better fill the screen. Below is what I came up with.