ColorCNC Colorlight 5A-75E/5A-75B as FPGA controller board

I think I was able to reproduce the lockout problem on the default target file of litex, on my PC running plain Ubuntu 20.04.
Submitted a sort of bugreport to litex people. I Hope they can reproduce and fix the problem.

I managed to implement the read function as well, using separate functions for read and write. Took some iterations, but with the version I have now, no more hangups of the board, even using a WiFi router to control it. 

Now working on a watchdog. This one consist of two sections:
- on the card, which have to be petted (during write) before time out happens (5 ms default, param exported to change this). Will put all outputs to zero, because the board does not support three-state controlled by the FPGA. When the watchdog is happy, one or more (configurable up to your liking) will be HIGH, when the watchdog bites, this pin will be Low. This gives a way to disable drives physically. 
- the driver also watches for dropped packets during read. Dropped packets adds to a counter, when the counter is to high (5 subsequent missed packets), the axe falls and communication is stopped. This means that the watchdog on the card will trigger 5 ms later as petting has stopped. The counter of missed packets is decreased every time a packet has successfully been sent. 

Will keep you updated when this has been pushed to the repo (at this moment only driver side has been done). 

Edit: Watchdog is done and reading data implemented (although packet collisions can occur).​​​​​
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Well, that was not the last version of the colorcnc driver

The original driver did some strange calculations on the step count that resultet in wrong stepper movements. I have fixed that. 

I have also included code to set the static ARP entry for the card from the driver. That unfortunately implies that the driver needs to know on which interface the card is connected, e.g. "eth0". This is defined in colorcnc.c.

I really hope that is now the last update. I will now move to the mechanics of my mill.

Cheers,
Inga
 

Thanks Inga for your improvements on the stability on the connection. Saw the issue as well at the LiteX-repository. Hope you won't mind I'll incorporate your changes in my version of   LiteX-CNC   .

Small update: included PDM with a resolution of 16-bit. Can be enabled by setting the PWM frequency to 0.

Also, I bought a second card to test the firmware out: a  RV901T  , which is also dirt cheap with 16 Euro + 7 Eur shipping. This card brings:

• dual Ethernet;
• 64 inputs / outputs. Direction can presumably be set by the FPGA in groups of 8;
• 32 outputs only (the buffer is hard-wired;
• The pins are nicely located in two headers and is designed to have a hat on top. Let's make a dedicated CNC hat for this card as soon as it is working.

The Colorlight 5A-75B/E boards are supported by IceStudio IDE for (Linux, Windows or Mac systems)
You only need a FT2232H, FT232H or USB Blaster JTAG programmer
More information in : icestudio.io/

 

And in my Github that explains how to connect and configure the JTAG boards in Windows --> github.com/benitoss/ColorLight_FPGA_boards

Can this IDE open the firmware of ColorCNC posted in the forum.