hostmot

Hi,

I am currently working on a project, in just few words I want to copy a Mesa board.
Mesa boards are based on Xilink FPGA, and there is the code available in these repo mksocfpga .
I want to use a Lattice FPGA, with all the Verilog toolchain that exists.

For the first "version" of it I want to make something like 7i76, connected via SPI to the computer (that may be a raspberry Pi?).
The computer will execute LinuxCNC and will use the parallel port(or GPIOs for the RPi) and talk with the FPGA.
On the FPGA I will have to reply to the computer in the right way...
Is there a file where I can find how the communication between computer and mesa card goes?
I would really like to receive opinions from people more expert than me in Linuxcnc and mesa card, does my project at least make sense?

Thansk anyone for the attention
mngr

Just a recap:
parallel port cards : Mesa and PICO
Eth cards : Mesa
SPI : Mesa and RPI 2/3
Parallel port not used as a parallel port but used as a communication bus on those cards in the example above.
SPI is used on PIDICNC cards for RPI 2/3 and it works nicely, and they are very versatile and configurable.
Is that a proof of concept or academic study or production? If the latter, what price point are you thinking about ?

It is an academic project, but there is some possibility that I will start producing them in some future.
as an academic project at the moment I am only concerned about the software, hardware design may come later.
thinking about price the target is 15-30$ of production cost, that may end in something near 60-100$ (take it with a lot of salt, I am not an hardware designer)
(I will use an evaluation board, maybe the right answer to your question is "proof of concept")

>PIDICNC_3811
Exactly!!! I want to do something very similar to that! (just, with a Lattice ICE40 as FPGA, and free software)
Is there a detailed description of this product available online? (a quick search found nothing)
Thank you very much, tomorrow I will look at configuration that works with that board

> Ethernet cards Mesa
One remote dream of mine is connect that board to a PC via ethernet (like 7i76E), but now I prefer to concentrate on the FPGA side.

Hi Marco,

The software is not the problem. Search on Mesa filmware. It's free to use.

The hardware side is difficulter to copy. I would start with a nice fpga chip and try to make a connection
by modificated filmware trough the fpga i/o.

Hi Grotius,

I want to use opensource tools, so my project is mainly convert some part of that VHDL code to Verilog or MyHDL and compile them for some Lattice ICE40 FPGA.
Right now I am looking for the software (linuxcnc-side) that talks with the FPGA, I am looking in hostmot2.c, is this the right place?

The 7i90 communicates with SPI.

The 7i90 firmware source can be found here:
github.com/LinuxCNC/hostmot2-firmware/tree/master/src

I know that at least two people have made their own hostmot2 hardware.