Users of the Digilent Cmod S7 FPGA evaluation board might be interested in this high-performance Forth computer implementation.

The users' manual (forthBoard.pdf) can be downloaded from
https://drive.google.com/file/d/1PN6igK_-DLcrx2OWT1H5mXyfrT4OAAq3/view?usp=sharing

Cheers

On Thursday, April 7, 2022 at 8:28:40 PM UTC+2, Myron Plichota wrote:
> Users of the Digilent Cmod S7 FPGA evaluation board might be interested in this
> high-performance Forth computer implementation.

That looks like a *very* nice board. Only 61 in stock (in Switzerland), for 67 Euro.

-marcel

> That looks like a *very* nice board. Only 61 in stock (in Switzerland), for 67 Euro.

Thank you, Sir.

Would you please send me a link to the Swiss vendor? In North America (Canada), there is no stock, and lead times have gotten worse over the past few months at DigiKey and Mouser.

- Myron

On Friday, 8 April 2022 at 11:54:48 UTC+1, Myron Plichota wrote:
> > That looks like a *very* nice board. Only 61 in stock (in Switzerland), for 67 Euro.
> Thank you, Sir.
>
> Would you please send me a link to the Swiss vendor? In North America (Canada), there is no stock, and lead times have gotten worse over the past few months at DigiKey and Mouser.
>
> - Myron

I just asked google and a source for 11 is today is Rapid
https://www.rapidonline.com/digilent-410-376-cmod-s7-breadboardable-spartan-7-fpga-module-67-0007

> I just asked google and a source for 11 is today is Rapid
> https://www.rapidonline.com/digilent-410-376-cmod-s7-breadboardable-spartan-7-fpga-module-67-0007

Thank you, Sir.

- Myron

On Friday, April 8, 2022 at 7:19:07 AM UTC-4, Myron Plichota wrote:
> > I just asked google and a source for 11 is today is Rapid
> > https://www.rapidonline.com/digilent-410-376-cmod-s7-breadboardable-spartan-7-fpga-module-67-0007
> Thank you, Sir.
>
> - Myron
Thanks again Jurgen. I ordered 3 from Rapid. - Myron

On Friday, 8 April 2022 at 14:59:58 UTC+1, Myron Plichota wrote:
> On Friday, April 8, 2022 at 7:19:07 AM UTC-4, Myron Plichota wrote:
> > > I just asked google and a source for 11 is today is Rapid
> > > https://www.rapidonline.com/digilent-410-376-cmod-s7-breadboardable-spartan-7-fpga-module-67-0007
> > Thank you, Sir.
> >
> > - Myron
> Thanks again Jurgen. I ordered 3 from Rapid. - Myron
it is a pleasure to help.

On Friday, April 8, 2022 at 12:54:48 PM UTC+2, Myron Plichota wrote:
> > That looks like a *very* nice board. Only 61 in stock (in Switzerland), for 67 Euro.
> Thank you, Sir.
>
> Would you please send me a link to the Swiss vendor? In North America (Canada),
> there is no stock, and lead times have gotten worse over the past few months at
> DigiKey and Mouser.
If you try to `buy' something at the Digilent site that is out of stock, they show you
the distributors that still have some.

They also warn when an item is obsolete. That was a bit worrisome (cycles of
half a year...). One shouldn't buy until one really wants to use it immediately as-is.
(I talk from experience, being the proud owner of a `bargain' MC68881 that never
saw a socket because it became outdated before my soldering iron heated up).

-marcel

"myronp...@gmail.com" <myronplichota@gmail.com> writes:
> The users' manual (forthBoard.pdf) can be downloaded from
> https://drive.google.com/file/d/1PN6igK_-DLcrx2OWT1H5mXyfrT4OAAq3/view?usp=sharing

This is nice, is it your design? It reminds me a little of the b16 and
GreenArrays cpus, which I guess is unsurprising. Can you run it on
other FPGA boards? How many LUTs etc. does it require? Are you going
to make a chip? You can get it fabbed in 130nm for free:

https://www.fossi-foundation.org/2020/06/30/skywater-pdk

It would be cool if someone here did that.

On Friday, April 8, 2022 at 8:52:17 PM UTC-4, Paul Rubin wrote:
> "myronp...@gmail.com" <myronp...@gmail.com> writes:
> > The users' manual (forthBoard.pdf) can be downloaded from
> > https://drive.google.com/file/d/1PN6igK_-DLcrx2OWT1H5mXyfrT4OAAq3/view?usp=sharing
> This is nice, is it your design? It reminds me a little of the b16 and
> GreenArrays cpus, which I guess is unsurprising. Can you run it on
> other FPGA boards? How many LUTs etc. does it require? Are you going
> to make a chip? You can get it fabbed in 130nm for free:
>
> https://www.fossi-foundation.org/2020/06/30/skywater-pdk
>
> It would be cool if someone here did that.
Dear Paul,

It is my design, but is influenced by Chuck Moore's chips Mup21, F21, and ShBoom.

Being written in Verilog, the possibility of implementing it on other FPGA platforms is open. But note that the Xilinx Vivado wizards used to generate the Series7 MMCM clock generator and XADC A/D convertor IP cores produced files with prominent copyright notices, so they are missing from from my source files offering. FPGA pin number/attribute assignments would also need to be redefined.

Resource usage:
LUT 907 of 14600
FF 934 of 29200
BRAM 36 of 45
DSP 2 of 80
IO 56 of 150
BUFG 2 of 32
MMCM 1 of 3
(no XADC report!)

Being reliant on many Series7 hardware fabric features, I have no desire to attempt a chip fab, PCB design, SMT board assembly, etc.

I hope to spark a community of Cmod S7 users that shares their hardware/software adventures like in the pioneering 8-bit days. AFAIK, there have been hundreds (if not thousands) of units purchased by end users like me.

My next steps:

1) Acquire 3 more units (ordered, awaiting delivery).
2) Attempt to burn fresh units using Xilinx Vivado from the existing config files. This would skip rerunning the MMCM and XADC (GUI) wizards and the synthesis and implementation phases.
3) Document the resulting procedure and revise the users' manual to include it.
4) Continue to provide a zipped snapshot of the design files and forthBoard applications source code examples to anyone who requests it, for free.

- Myron

On Saturday, April 9, 2022 at 9:28:51 AM UTC-4, Myron Plichota wrote:
> My next steps:
>
> 1) Acquire 3 more units (ordered, awaiting delivery).
> 2) Attempt to burn fresh units using Xilinx Vivado from the existing config files. This would skip rerunning the MMCM and XADC (GUI) wizards and the synthesis and implementation phases.
> 3) Document the resulting procedure and revise the users' manual to include it.

These 3 objectives have been accomplished. Also, the new users' manual includes a link to the zipped design files. Please see:
https://drive.google.com/file/d/1PN6igK_-DLcrx2OWT1H5mXyfrT4OAAq3/view?usp=sharing

- Myron