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They don't _have_ to be:

0 = 7i77 #1 digital I/O
1 = 7I77 #1 analog output
2 = 7I77 #1 expansion channel

Buts that's the way the standard firmware arranges them.

This one says height sensor is Ethercat or +- 10v
alleriastore.com/products/automatic-lase..._fid=c31262f39&_ss=c
Some of their  controller packages refer to a TTA interface but don't describe it anywhere
alleriastore.com/products/automatic-lase..._fid=c31262f39&_ss=c

Having a more open spec rather than closed source will be much better anyway.

As noted the MicroSD card has the OS and LinuxCNC. It has the KiCad files. It also has the data sheets and documents for boards and components used on the boards I made.
 

Here is a screenshot of the system running. The Pi is mounted on the 7C81.
 

Here are screen shots of the directories with the included files mentioned above.
 
 

If you have any questions you can email me directly at This email address is being protected from spambots. You need JavaScript enabled to view it.

Best

I was planning to use this controller setup for a Precision Matthews 728v-t mill using Teknic ClearPath SD servos. I was not keen on interfacing to the servos and mill spindle directly from the FPGA card, so I designed a 3v - 5v level shifting buffer / isolation card. I did the design in KiCad and all KiCad schematic and PCB files are included on the microSD card. Here is the schematic of the card.

 

Here is how the card was going to be used in this controller setup. The 7C81 had been flashed as a 5ABOBX3D.  There are three cards because the minimum board order was three. I decided to build out all three in case there was an issue with one, and to have spares. The boards have been powered up and tested. They are fully functional.

Obviously given HAL you don't have to use the board exactly as I intended.

 

Here is the how the controller power was planned.

 

rodw wrote:

Also I noted that on some laser cutting solutions the capacitive BCL-AMP is being superceded by amplifiers with a 0-10 volt signal?

could you give an example / link ?
I was looking some time ago for such sensors but I found only one that did not meet my requirements.

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.

Peter,
Thank you. I can see the logic behind that, what I think was lost is the significance of the channel numbers and why I'd have to use the third channel for this card.
I think I see it like this. The sserial instruction is to the host card ie 0, (7i92, ) in my case. Plugged into which is a daughter, could be two of them, but only one (7i77) here, and that's therefore channel 1, and lastly, the smart serial card 7i73 that hangs off the 7i77must be channel 2

I get it in version 2.9.4.
everything worked during the day, broke in the evening.
how can I fix this?
where to find "sticky threads"

The sserial_port_0 parameter sets the modes for sserial channels 0.N in
left to right order of channels so sserial_port_0=001xxxxx means set

sserial channel 0 -> mode 0
sserial channel 1 -> mode 0
sserial channel 2 -> mode 1
sserial channels 3..7 = x = disabled

The channels used in a a particular FPGA configuration can
be determined with mesaflash's --readhmid command

At the beginning of this post there was a demonstration using only USB Networking (No Ethernet).
Does this function still exist?
I was able to build and install to an ESP32-WROOM, but boardconfig keeps setting to "Wowki Simulator ESP32".

rodw wrote:

prokopcio wrote:

I suggest 20-70kHz (0-10mm) and 10kHz(or 0Hz) = collision
This is linuxcnc. We will not have collisions!
Maybe  collisions are 5 kHz and our rule is: if < 10 kHz, report a collision

in fact, anything below 20 kHz is a collision.

higher frequencies mean faster response, which is very important for collisions.

hi blazini,
I also think that digital/serial transmission is a very good solution.

I have to think about it because the output that I have available in the sensor is an open drain output and it would require a simple converter but it is not a problem to add it. These are just a few basic elements to adapt to various interfaces such as RS485, RS422, RS232 or UART TTL.

I do not foresee standard protocols such as MODBUS etc. with bidirectional communication due to the too long time of exchanging transmission frames.

I do not want to use a high transmission speed so that the quality of the connectors and cables does not affect any possible distortions.
I want to transmit every 1ms only 4 bytes (start byte, 2 data bytes, crc) at a speed of 57600 but it is possible that I will change the assumptions.
Could you handle something like this?
If you have other ideas, they will be welcome