What FPGA content would you like to see?

Im enthusiastic to work more with fpga's, after my current project I intend to make a multi protocol analyzer, Jan Cumps mentioned he's made one using an fpga so I might follow suit here.

Also I want to add a graphical interface of some sort (lcd) so I'll likely use a small board computer for that part as I feel that would be easier and an fpga for the bus reading and decoding and make a standalone piece of test equipment so expect some more content from me

Im enthusiastic to work more with fpga's, after my current project I intend to make a multi protocol analyzer, Jan Cumps mentioned he's made one using an fpga so I might follow suit here.

Also I want to add a graphical interface of some sort (lcd) so I'll likely use a small board computer for that part as I feel that would be easier and an fpga for the bus reading and decoding and make a standalone piece of test equipment so expect some more content from me

lucie tozer wrote:

 

Im enthusiastic to work more with fpga's, after my current project I intend to make a multi protocol analyzer, Jan Cumps mentioned he's made one using an fpga so I might follow suit here.

 

Also I want to add a graphical interface of some sort (lcd) so I'll likely use a small board computer for that part as I feel that would be easier and an fpga for the bus reading and decoding and make a standalone piece of test equipment so expect some more content from me

lucie tozer wrote:

... after my current project I intend to make a multi protocol analyzer, Jan Cumps mentioned he's made one using an fpga so I might follow suit here.

 

...

I blatantly stole someone's design

The Papilio boards and Dangerous Prototypes LogicSniffer are virtually the same hardware - except input protection and level shifting.

So the only thing I did is to make input protection board and load the LogicSniffer bitstream (I just changed some pull-up settings in the constraint file - the standard ones loaded some circuits a bit too hard).

I've got a blog on that here on e14. I'll search it ...

Here is the explanation:

Make a Logic Analyzer from your Dev Kit Part 2: Papilio FPGA

Once you had that going, it might be interesting to see if you could move the processor to the FPGA. A custom processor, designed to be good at the kind of tasks you'd want in such an embedded type application, might look quite different to the kind of thing we're all used to which has to be a 'Jack of all trades'.

That would be awesome but thats probably out of my depth, and probably more than just 1 person can manage. My first thoughts are a custom processor needs a custom command set and then a custom compiler for a higher level language to make it functional for things like graphical work.

Maybe its not as complicated as that though, I might look into it as a potential option. Right now Im not proficient enough with FPGA's to develop a processor inside one!

The vendors have code for soft processors.

The Altera one is called NIOS. Downside is that I think you have to pay for licence if you ship it as part of a product.

Xilinx have the PicoBlaze (8 bit) and MicroBlaze (32 bit) - they seem to be free for development but again may have licence restrictions (I haven't looked in detail).

I don't have any experience of either, so can't say how easy they are to use or what the supporting toolchains are like.

If you had a look at the code for the PicoBlaze it would give you an idea of what's involved with a very simple microcontroller - that will be about as simple as it gets, unless you did a calculator-style 4-bit processor. Copy Intel's 4004 maybe? https://en.wikipedia.org/wiki/Intel_4004

Alternatively there are SoC type FPGA's which have a whole bunch of stuff including Ethernet, Memory controllers, an ARM core etc all tightly coupled with the FPGA fabric. Something like the MicroSemi SmartFusion2 range: https://www.microsemi.com/products/fpga-soc/soc-fpga/smartfusion2#product-tables

Then do what makes most sense in traditional software on the ARM core and build custom hardware in the FPGA part for where this can really help out.

I'm also interested in implementing a minimal RISC-V processor using an FPGA. It is open source and as far as I know does not have any license restrictions.

There is also the Xilinx Zynq-7000 series which have single or dual core ARM processors and 25K -  85K logic cells (~400K to ~1.3M "ASIC gates")  FPGAs.

There are a couple of companies that offer boards based on these chips (I bought a Snickerdoodle), they are fairly expensive starting at ~95 USD but they

also have SDRAM, a large number of available I/O connections to the ARM core peripherals and the FPGA, and in the case of the Snickerdoodle, Wi-Fi.