Depth setter / tool length input?

[thackman]

As anyone automated the process of zeroing out an endmill after a tool change? I've seen several examples in the minimill forum but haven't found any substantial documentation on the Syil breakout board. I'm thinking of building a simple one out of scrap a piece of PCB and some Mach3 macros that were posted in the mini mill forum. The Syil manuals says it has two inputs w/ pullup resistors, they are pins 1 and 7 on the parallel port but they aren't labled on the board. Since they have pullup resistors I'm assuming they are always high and I just need to ground them to take them low. I just don't want to burn something up experimenting.

I'd also like to add an additional E-Stop switch outside my enclosure. I don't like the idea of having to get closer to the mill to hit the E-stop when something goes wrong. Any advice on where to tap into the E-Stop system would also be appreciated. I haven't had a chance to determine if it's normally open or normally closed and if they are series or parallel. I'm assuming that the E-Stop on the breakout board is just an input for Mach and the actual E-Stop functionality is handled by one of the other boards.

Parallel Interface PCB:
• 4 Axis support
• 4 Axis limit / home support
• Direct support for all common PC controller software (Mach, KCAM, Etc.)
• Support for spindle control (DC power, AC power, frequency conversion)
• Photocoupled input/output protection
• Emergency stop
• 2 Aux inputs/outputs (Coolant, Probe, Tool height, etc.)
Technical:
Power: DC 13-18V, AC 12-16V (50-60Hz)
Current at idle: 9mA
Current at full: 100mA
Output drive voltage: 5V
Output current: ~2mA
Input signals: Pull-up resistors

I'm attached the standard Syil image of the breakout board. When I have the case apart this weekend I'll take a picture of the version that I have.

[iGG1e]

The emergency stop on the SX3 is normally closed. I have effectively added two switches to mine. Currently I've used the point where the mill wiring ends at the front panel switch to patch into. One of them will stay connected at this point due to what it does and it's location, the other one is an external switch and I will move those connections to the inside of the electronics housing as it will mean I can reduce the wiring length. Not easy for me to get into the back of the mill, so it will wait until I have to take it apart again.

I use the touch probe modification to Mach3 and the A axis home input to do the sensing as I don't think there is anything else spare...could be wrong.