Re: [CAD_CAM_EDM_DRO] Bridgeport CNC Mill???

Les Newell wrote:

> Both Mesa and Jon's hardware
> will count at several MHz.
>
>

Actually, my stepper controller will only read to ~ 500 KHz with
guaranteed reliability,
the PPMC and PWM controller to about 1 MHz. Nobody has found that to be
a limitation, yet.

>>
>
> IMHO that is the biggest disadvantage of EMC. No two machines have the
> same requirements and it is very handy to be able to customize the
> screen layout to suit.

Well, here's the HAL code to display spindle speed on an additional
panel to the Axis GUI:

# spindle speed display
addf lowpass.1 servo-thread
net spinraw ppmc.0.encoder.04.delta conv-s32-float.0.in
net spinfloat conv-s32-float.0.out mult2.0.in0
setp mult2.0.in1 185.185185 # (60/encoder count/rev)
net rawSpindleRPM mult2.0.out => lowpass.1.in
setp lowpass.1.gain 0.02
net SpindleRPM lowpass.1.out pyvcp.SpindleRPM

This gets spindle speed from the spindle encoder and converts it
to RPM, then runs it through a lowpass filter to get rid of
fluctuations in the reading due to the low resolution of the
encoder. Then, you provide a short XML file to describe the
item to be displayed on the PyVCP panel :
−<pyvcp>
−<label>
<text>"Spindle Speed:"</text>
</label>
−<bar>
<halpin>"SpindleRPM"</halpin>
<max_>5000</max_>
</bar>
</pyvcp>

That's it!

Jon