do people who know c language and assembly language, who have experience in programming micro-controllers like zilog, atmel and pic ....can easily adapt to using this? like doing the stuff  that you are doing? create firmware for this FPGAs

the lack of developers in this arena and the lesser utility/other uses of FPGA (in general population) makes me think twice in investing more in this kind of stuff...unless i knew a guy in person that i can work with, not just some random guy in the internet..

I get the general idea but I still have a hard time seeing how to do that with the USB-UART pins.

As far as 'resale' of these FPGA cards, there is also a tremendous future for AI mining.  In fact, if tens of thousands of people were mining crypto with these boards, and an AI mining server became available, they are so powerful that you might end up with a 'Skynet' type superintelligence, or the Kurzweil 'singularity' event. 

My point is that if, for some reason, mining crypto became unprofitable, someone could re-sale access to the FPGA hardware for AI, weather prediction or any other compute-heavy tasks.

It doesn't help much and in my opinion it is actually detrimental. Those devices you mentioned have the similar conceptual limitation: they encourage thinking of solving tasks in terms of sequences of steps. Very much like many early "home computers" programmable with BASIC.

The thing is that a random guy can conceivably be much better at FPGA programming, even without previous exposure to computers.

I believe it starts much earlier and is conditioned with the type of toys one played as a kid. Here's my theory:

If as a kid somebody played

(1) with mechanical toys that allow to build working things out of building blocks

or

(2) with electrical toys that allow building working circuits out of components connected with pluggable wires

then as an adult such person will have natural aptitude for

(a) FPGA programming

or

(b) parallel programming

or

(c) electronic engineering

To such a person the FPGA development kit is very much like their dream toy from the childhood upgraded to a true professional tool with nearly unlimited quantity of building blocks and connecting wires.

So I disagree with your premise that the aptitude for FPGA programming is rare, it just isn't discovered and developed in many people.

In the past I was frequently surprised that some people with advanced computer science degrees from reputable schools have extremely hard time understanding that some device can concurrently work doing many things simultaneously. No need to explicitly state the order in which things need to be done.

You may now know it, but FPGAs don't need to be programmed using some language like Verilog or VHDL. They can be designed using schematic capture of assembling blocks and connecting them with wires. And this comes naturally to some grade school kids with no computer science exposure whatsoever.

So the TL;DR of the above is: it really depends on what kind of toys you played with when you were a kid.

I get the general idea but I still have a hard time seeing how to do that with the USB-UART pins.

As far as 'resale' of these FPGA cards, there is also a tremendous future for AI mining.  In fact, if tens of thousands of people were mining crypto with these boards, and an AI mining server became available, they are so powerful that you might end up with a 'Skynet' type superintelligence, or the Kurzweil 'singularity' event. 

My point is that if, for some reason, mining crypto became unprofitable, someone could re-sale access to the FPGA hardware for AI, weather prediction or any other compute-heavy tasks.

If you are data center guy such as myself, then you may prefer these server cards.

Lead time is 2 weeks:
https://www.xilinx.com/products/boards-and-kits/vcu1525-p.html#hardware

I do not trust PCIe risers with $4K hardware, there are some brave souls out here.

If i were to buy just one of theese cards, could i not just put it in my computer then as it fits in the PCI slot? But communicates through usb and only use PCI for power was that it?

I get the general idea but I still have a hard time seeing how to do that with the USB-UART pins.

Just for some background, we have been shipping this board for 1.5 years now, and have had almost no field failures.  It has gone through full validation, including thermals.  We manufacture in the US using a Tier 1 contract manufacturer. Our standard warranty is 1 year, we have some products with 3 year warranties, and some customers who pay for extended warranties.  We also generally provide unlimited support, as our normal customer is one who buys 10s or 100s (or even 1000s) of boards.  We have been building high reliability boards for decades, with one of our boards being used as part of the traction control system on the TGV (and all Alstom train and subway cars) for well over 10 years.

When this mining opportunity came up, we looked for ways to provide a deep discount as we know this community is very cost sensitive.  We also have concerns with the way that these boards will be used for mining, mostly from an ESD point of view.  Our normal customers install these boards in servers, and are in properly controlled environments with ESD protection taken very seriously.  So we lowered the warranty to reduce cost, and for fear of the boards being abused.  Perhaps we went too far lowering it to 30 days.  We also limited support, however, our normal support includes helping people develop their FPGA code on our board.  In this case you are using code already developed.

Note that we do have onboard monitoring for temperature, voltage, and current, with thresholds set to shut down the board if it appears to be entering a situation that would cause damage.  We provide a utility (console and GUI versions) that you can use to talk to this onboard controller via the USB and see what is going on with all the sensors.  Unlike GPUs and CPUs, FPGAs have no inherent thermal throttling, unless the FPGA developer builds that into their logic, which is very rarely done.  FPGAs also burn more power as they get hotter, so from a power efficiency point of view, it is better to keep them cool.

As for cost we presented, while I know it seems steep for this community, this is deeply discounted from our standard price, taking into account the reduced warranty and support.

From what I can tell, Xilinx has a 90 day warranty on their devkits, which is what the VCU1525 is.  I'm not sure how long they will sustain that low cost, we know of smaller board manufacturers that pay more than that for just the VU9P chip itself.

do people who know c language and assembly language, who have experience in programming micro-controllers like zilog, atmel and pic ....can easily adapt to using this? like doing the stuff  that you are doing? create firmware for this FPGAs