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For sale as a group. $500 US shipping included.

MESA 7C81 is FPGA motherboard host for a Raspberry Pi
1.5" RPI GPIO cable for 7C80 and 7C81
DIN Tray 107MM X 102MMFor 7C81

Raspberry Pi 4 Model B (8 GB).
Includes SanDisk Ultra 32GB microSD card with RT PREEMPT 6.6 linux kernel version of Raspberry PI OS. See this thread regarding installation.
Pi heatsinks, power cord, fans.

KBSI-240D (9431) Signal Isolator. DIN tray for this card.

2 DPDT Signal Relay Module Board, DC 24V . DIN tray for this card and PWM card.

Ideal Power's 56YSD15S 24v DC 15W DIN Rail Mount power supply

3.3V PWM to 0 to 10 V Voltage Converter . DIN tray for this card and Relay card.

Three signal isolation cards I designed and fabricated. DIN tray for this card. Ribbon cables from 7C81 to signal isolation board. Connectors and pins for the connectors that mate to the signal isolation board.

Cards are described in detail in the next post.

 
 
 
 
 
 
 
 


 

This is "only" a sensor that transmits the distance value to the CNC System. The CNC System must be able to use it.

If you have any ideas how i can help, I would be grateful for your advice.

At the moment I have accepted that the frequency will be the best solution.

so I implemented freq. scale
0-10mm -->> 20kHz - 70kHz   (10kHz = colision )
( each of steps 0.05kHz = 0.01mm ).
It works exactly as it should.
of course is availabe analog output 0-10V and you can use the analog output or frequency (a square 50% duty signal and any voltage) depended what you need.

first test frequency output on my desk :

Linuxcnc is not really designed for serial transmission in real time.
Yes, Mesa has its smart serial interface that it uses principally for its own daughter cards but its not well developed for third party devices. It would add additional development complexity. Plus it would limit the hardware platform that could be used with Linuxcnc.

Using frequency or a voltage is well understood and easy to decode and support on different hardware
With the emergence of Ethercat controlled laser cutting heads, its important to consider a wider audience and how it can be incorporated into an Ethercat machine.
Also I noted that on some laser cutting solutions the capacitive BCL-AMP is being superceded by amplifiers with a 0-10 volt signal

I think Proma needs to gives some thought on to how to keep their audience as broad as possible. I think that while using a frequency read by an encoder is quite simple and broadly available, 0-10 volt may open the device up to a broader audience but may not have the advantage of sensing collissions etc via specific frequencies.  Using serial communications reduces the audience to Linuxcnc users using specific hardware. I think frequency sounds the most flexible now.

Finally a question about frequencies. How would you sense a void? eg say you wanted to find the material edge so the axes can be rotated around the Z axis to account for a skewed sheet? Or to sense the edge of a sheet when severing it to turn off the laser?

Yes, RPi suggests that parallel processing 1.5x that number of cores works well. I had also always used the number of cores.