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Nexys Video HDMI


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Hi all,

 

I am considering purchasing a Nexys Video dev board soon, but I have noticed the HDMI port is not connected to the GTP ports on the FPGA, just the standard IO ports. So I am wondering, can this board do 1080p 60fps with 24-bit RGB colour?

 

According to this screen shot from the HDMI demo on the digilent website it appears that it can but I’m not sure how??

nv-hdmi-tera-change-res.png?cache=

 

I believe the HDMI standards states 1080p 60fps with 24-bit colour (8- bits per colour) requires 4.46 Gbps.

 

The Artix-7 standard IO is only 950 Mbps for LVDS at 2.5v, so I presume the 3.3v TMDS will be a bit faster, but not fast enough for 1080p60, as over 3 differential pairs (TMDS 0-2) would be a total theoretical limit of 2.85 Gbps.

 

So how can the Nexys video do 1080p at 60fps with 24-bit RGB colour over HDMI? As I’m not really seeing a clear cut answer as to how the demo seemingly accomplishes this.

 

It looks like it should not be possible, but the digilent demo says otherwise. Anyone care to explain how this is accomplished?

 

I can see the FPGA connects to a TI “HDMI Hider” (as it’s called by TI), but that seems to do little more than improve the signal integrity before being passed on.

 

Or am I missing something?

Edited by Mario875
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5 hours ago, Mario875 said:

Or am I missing something?

Yup.

HDMI uses the TMDS standard and the Nexus Video does a good job implementing it. The mDP ports however do use two GTP transceivers per port. The Genesys2 is even better with 4 GTX transceivers per mDP port. Both boards are good platforms for video projects. You are correct about the Artix clocking limitations. The Kintex on the Genesys2 does better. Even the Spartan6 on the ATLYS board does better.... though Series7 devices have superior clocking than Spartan 6.

Be careful with the HMDI as TMDS uses 50 terminators and you can experience power supply issues with whatever is connected on the other end of the HDMI cable.

You'll have to do you due diligence to determine what platform is best for your video needs. An alternative to the Nexys Video is the Numato Labs Mimas-A7 which is also an Artix board but with a smaller part than the Nexys Video A100T. I've used all of these for successful project development.

The IO banks on the Nexys Video and Genesys2 boards for the HDMI ports use Vccio = 3.3V so, even if the board design allowed for LVDS ( they don't) the Diligent boards can't so LVDS. It's complicated.. so do your homework if you have certain video requirements to meet.

 

Edited by zygot
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Posted (edited)

Thanks for responding, however that doesn't really answer my question. Please see below responses to your answer.

 

7 hours ago, zygot said:

HDMI uses the TMDS standard and the Nexus Video does a good job implementing it.

I am aware HDMI uses TMDS, I suppose that is my query, how does the Nexys video implement it to achieve [email protected] with 24-bit colour on their built-in demo?

 

7 hours ago, zygot said:

The Genesys2 is even better with 4 GTX transceivers per mDP port. Both boards are good platforms for video projects. You are correct about the Artix clocking limitations. The Kintex on the Genesys2 does better.

Genysys 2 look great, but is about double the cost and if I am not mistaken the Kintex requires a Vivado licence which I believe is included for 1 year with the Genysis 2, but then requires to be paid for, so not really an option for me due to the cost.

 

7 hours ago, zygot said:

An alternative to the Nexys Video is the Numato Labs Mimas-A7 which is also an Artix board but with a smaller part than the Nexys Video A100T. I've used all of these for successful project development.

I have just had a look at that, seems like a nice little board (website says it uses the A50T though), but I think the Nexys video still offers me more flexibility due to having the A200T, as they both have 160-pin breakout headers, of which about half (think just over half on the Nexys Video to be honest) can be used for GPIO.

 

The Numato board also has it's GTP transceivers all used up with the mini display port connection, the Nexys Video at least has 1 GTP transceiver on the FMC connector should I ever need it.

 

For my project I have considered (at least to begin with) I could implement it using a HDMI transmitter like the ADV7513 via a breakout board through the FMC connector on the Nexys Video, then come back later and try to eliminate the ADV7513 and implement it directly on the FPGA (hence these questions).

 

7 hours ago, zygot said:

The IO banks on the Nexys Video and Genesys2 boards for the HDMI ports use Vccio = 3.3V so, even if the board design allowed for LVDS ( they don't) the Diligent boards can't so LVDS. It's complicated.. so do your homework if you have certain video requirements to meet.

 

I understand that, the only reason I mentioned LVDS is just because that is what the Xilinx datasheet refers to when discussing performance characteristics. According the the datasheet, the -1 speed grade (as is used on the Nexys video I believe) has a max transmitter / receiver speed of just 950 Mbps.

 

So 950 Mbps x 3 TMDS pairs gives a max bandwidth of 2.85 Gbps. The HDMI standard states 1080p, 60fps, 24-bit colour requires 4.46 Gbps. Even if we have zero blanking area and do some quick math we get 1080 * 1920 * 60 * 24 = 2.985 Gbps

 

This is without any blanking area in the transmission and with just taking the 8-bit per colour. TMDS uses 10 bits per colour as 2-bits are used for control signals during the blanking period, so realistically, even with no blanking period we would be looking at 1080 * 1920 * 60 * 30 (10-bits per colour) = 3.73 Gbps

 

Neither of these figures should be achievable (without over clocking) on the Nexys Video Artix-7 with the -1 speed grade FPGA.

 

So kind of going back to my original question. How have Digilent achieved this?

 

As a side note, my project is going to be taking in 24-bit RGB from an external device and outputting over HDMI. As I have mentioned above, I have looked at just using an ADV7513 to transmit the HDMI and get round this. However, seemingly Digilent have found a way to make it work, and I am trying to understand how have they done it?

 

As it may mean I can avoid using the ADV7513, at least in future revisions of my design, even if not initially.

Edited by Mario875
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I don't think that Digilent has any published information that warrants a particular video standard or color depth for the Nexys Video HDMI capabilities. I don't know of an FPGA board vendor who isn't happy to sell stuff to people who make poor assumptions... that's just the nature of the industry.

Typically, in the FPGA development board space it is up to the customer to determine if a particular board meets the requirements of a project's needs.

There is more to this than just hardware. Can you write own video IP or do you need to use free, or purchased, IP? Free IP tends to come and go with FPGA vendor tool versions. For certain applications where they think that then can monetize the IP assume that free IP that supports your specific needs isn't available. As you point out, the Kintex requires a license to create a bitstream. For the Genesys2, Digilent provides a voucher for a license that will be tied to one development host. This is a permanent license that lasts as long as your development PC host. The 1 year term refers to the tools versions updates that will honor that license. While not perfect, it's better than what other FPGA vendors will offer.  BTW, my recent Kintex 325T license that came with the Genesys2 also is usable for the NetFPGA-1G-CML board using the same device but in a different package. And it works with ISE 14.7. I have a similar node-locked license for a different FPGA device that Xilinx let me transfer the license to a different PC; that was a couple of years ago. Unfortunately, the tools that I use on the new platform don't support this particular, Xilinx branded, board the ZCU106... which is quite disappointing considering the cost of this board.. and the fact that I bought it from Xilinx. Disappointing, but not surprising to anyone who'd been doing FPGA development for a while.

Unfortunately, for video doing your due digilence isn't always easy to do. Sometimes video IC vendors have FPGA board project code available for a few boards. Usually, projects involve more than just pumping bits through a hardware interface, so you have to do a rough estimate of the timing capabilities for a particular FPGA device and speed grade for a complete project.

One way to assure that a potential FPGA platform will be adequate for a particular project ( and that isn't a simple question to answer ) is to find code examples for that board that you can build with the tools that you have. In fact, you can try to do this with the demo projects for the Nexys Video; it's part of doing your due diligence before making a purchase.

For high end video there are boards that support 6G and 12G SDI; but this doesn't fit your specific needs. Again, "buyer beware" is the customer mantra.

The best answer that I have to your specific question about the Nexys Video capabilities is don't make assumptions and do you best to verify that whatever platform you choose will work for you. Fortunately, you can build any project that's published and get a chance to analyze the results without having to make a purchase.

I forgot to mention that the Nexys Video has a LPC FMC connector and the Genesys2 as an HPC FMC connector. Both are well designed and support transceiver interfaces to mezzanine boards. That's a whole different topic as few board vendors guarantee that any particular mezzanine card will work with their board.... The add-on card capability does offer some hope of  using a board for a particular project, though with even more expense and homework to perform.

Edited by zygot
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Download "vivado-library" and the constraints repo. Nexys video has its own ip to get hdmi output based on oserdese2, its source code is available in the IP itself. It's called "rgb to DVI". It's enough to get 1080p withut problems. You have to put a clock wizard with pixel and serial clocks to make it flexible for any hdmi or DVI mode. I Have a "bare bones" design to get video from hdmi with that. I will upload it to my repo soon

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1 hour ago, coldfiremc said:

Nexys video has its own ip to get hdmi output based on oserdese2

Good point. I'm not sure why I forgot about OSERDES2.

Your post also illustrates my reluctance to recommend a particular platform for anyone's needs. It is non-specific enough to be misleading ( I'm sure that this isn't your intention... but that's my point ) but not specific enough to conclusive. The Artix clocking specifications are limited for the Nexys Video speed grade. @Mario875is adamant about non-interlaced 1080p with a 24-bit color depth. Is that what you implemented?

There are always those vital little details that get missed on discussion platforms like this that cause confusion because they aren't addressed.

It's easy to forget that general purpose low cost FPGA development boards like the kind that Digilent offers is just that: general purpose learning platforms. They are not necessarily appropriate for demanding professional quality applications.

Edited by zygot
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Posted (edited)
5 hours ago, zygot said:

I don't think that Digilent has any published information that warrants a particular video standard or color depth for the Nexys Video HDMI capabilities.

I do think you are correct there and I have possibly assumed a 24-bit colour depth as it's generally fairly standard these days, but as they say "to assume is to make an ass out of you and me".

 

5 hours ago, zygot said:

There is more to this than just hardware. Can you write own video IP or do you need to use free, or purchased, IP?

Ideally a free to use video IP would be preferred as it would make things go a lot smoother, this is also a bit of a passion project, so budget is reasonably constrained compared to a professional project.

 

5 hours ago, zygot said:

Unfortunately, for video doing your due digilence isn't always easy to do. Sometimes video IC vendors have FPGA board project code available for a few boards. Usually, projects involve more than just pumping bits through a hardware interface, so you have to do a rough estimate of the timing capabilities for a particular FPGA device and speed grade for a complete project.

One way to assure that a potential FPGA platform will be adequate for a particular project ( and that isn't a simple question to answer ) is to find code examples for that board that you can build with the tools that you have. In fact, you can try to do this with the demo projects for the Nexys Video; it's part of doing your due diligence before making a purchase.

I agree, as I've started digging into video and HDMI it seems to be a bigger and bigger rabbit hole! However that was partly what drew me into the Nexys Video. It has HDMI examples and projects already available and working on it which would help in implementing my own design. I agree that I need to do some rough estimates of the timing capabilities of an FPGA, that is exactly why I am here asking, as the Nexys Video demo can do 1080p @ 60Hz (albeit, without confirming the colour depth it's using) and it just seemed odd that it is doing that without using the GTP transceivers which is why I decided to ask, but maybe I need to dig a bit deeper into the FPGA datasheet.

 

Getting hold of some example code I can synthesis and simulate in Vivado sounds like a good idea though! Will definitely look into that.

 

5 hours ago, zygot said:

I forgot to mention that the Nexys Video has a LPC FMC connector and the Genesys2 as an HPC FMC connector. Both are well designed and support transceiver interfaces to mezzanine boards. That's a whole different topic as few board vendors guarantee that any particular mezzanine card will work with their board.... The add-on card capability does offer some hope of  using a board for a particular project, though with even more expense and homework to perform.

Yes the Nexys Video LPC FMC connector is something I have looked at, and it seems it should work for me if I decide to go down the route of making a custom add-on board with ADV7513, hopefully will help with getting my project off the ground, but I would ideally prefer to get it working without the need for the ADV7513. Or even as I suggested before, get the project up and running with the ADV7513 and then work on implementing the HDMI transmitter capability into the FPGA so I can eliminate the need for the ADV7513.

 

4 hours ago, coldfiremc said:

Download "vivado-library" and the constraints repo. Nexys video has its own ip to get hdmi output based on oserdese2, its source code is available in the IP itself. It's called "rgb to DVI". It's enough to get 1080p withut problems. You have to put a clock wizard with pixel and serial clocks to make it flexible for any hdmi or DVI mode. I Have a "bare bones" design to get video from hdmi with that. I will upload it to my repo soon

Oh, I just had a look at the vivado-library and it looks perfect! Thank you very much for pointing me in that direction. The rgb2dvi IP core PDF user guide says it supports a 24-bit RGB input and then outputting the video at up to 1080p @ 60 Hz (148.5 MHz) and is developed for the 7-series Xilinx FPGA's which is ideal.

 

However, have you personally tested it at 1080p, 60fps 24-bit colour depth? The pixel clock frequency of 148.5 MHz means the serial frequency would need to be about 750 MHz which the datasheet says the Artix-7 FPGA (at any speed grade) does not support (officially).

 

3 hours ago, zygot said:

Good point. I'm not sure why I forgot about OSERDES2.

Your post also illustrates my reluctance to recommend a particular platform for anyone's needs. It is non-specific enough to be misleading ( I'm sure that this isn't your intention... but that's my point ) but not specific enough to conclusive. The Artix clocking specifications are limited for the Nexys Video speed grade. @Mario875is adamant about non-interlaced 1080p with a 24-bit color depth. Is that what you implemented?

There are always those vital little details that get missed on discussion platforms like this that cause confusion because they aren't addressed.

It's easy to forget that general purpose low cost FPGA development boards like the kind that Digilent offers is just that: general purpose learning platforms. They are not necessarily appropriate for demanding professional quality applications.

According to the IP core PDF (https://github.com/Digilent/vivado-library/blob/master/ip/rgb2dvi/docs/rgb2dvi.pdf) it says that the IP supports 1080 resolution at 60Hz (148.5 MHz, which is the frequency required for 1080p) and supports 24-bit RGB input which is exactly what I need.

 

As for the clocking frequency of the Artix 7, this is where it seems to come a bit unstuck!

 

For the -1 speed grade FMAX_BUFIO is 600 MHz, the pixel clock will be 1/5 of that which is only 120 MHz, not the required 148.5 MHz! However even the fastest Artix-7 speed grade is only 680 MHz, not the required 750 MHz.

 

I have seen other posts on here and EEVBlog where @hamsterover clocked the FPGA to make it work, but it's not ideal.

 

Problem is the next step up from the Artix series is in Kintex and the cost is too prohibitive for me for this project as it costs about £1050 for a Genesys 2 vs the £450 for the Nexys Video.

 

Might be stuck with 1080i, or overclocking if I want to make use of the Artix and maintain HDMI specs. Either that or I just output RGB 24-bit video from the FPGA and let an ADV7513 deal with all the HDMI stuff as the input video feed is RGB 24-bit at 54 MHz. So the required bandwidth would be about 1.3 Gbps total which is well within the Artix-7 specs.

 

That way the FPGA can just do upscaling & de-interlacing of the original feed then output RGB to the ADV7513. Xilinx already provide a free IP core for upscaling / deinterlacing on the 7-series FPGA's.

 

EDIT: Interestingly enough, the Digilent IP core says it is for the Zynq-7000 and 7-series Xilinx FPGA's, but their FMAX_BUFIO is both the same. So the IP core can work with up to 1080p @ 60Hz, but neither FPGA it is developed for can support the frequencies required to achieve that (not officially at least)! 😕

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12 hours ago, Mario875 said:

As a side note, my project is going to be taking in 24-bit RGB from an external device

You don't mention what this is.

Looking at published project code isn't the same thing as running the tools on the sources and creating a bitstream. That step will tell you if you need any licenses, and what tool version headaches you might run into. You will also have a lot more information to work with examining the post route reports. Also, 3rd party IP may not do for your project what you want. Using it, and modifying the demonstration sometimes is informative.

Likely, the hardware interfaces are a minor part of any fun video project but the high speed ones using advanced IO features can certainly make the task of timing closure on a fully functional project a lot more difficult.

I understand your reluctance on spending twice as much for the Genesus2. All I can say is that the Kintex part on the Genesis2 is not the slowest part available and is much more capable than the A200T on the Nexys Video. But no one wants to waste money. You might think about future projects. Sometimes, but certainly not as a rule, higher initial investment can be a better ROI proposition. This is you call and yours only of course. It certainly depends on how much use you plan on getting out of the board. In general both the Nexys Video and Genesys2 are pretty good platforms for a wide range of interesting non-trivial projects.

Get to building those projects on your Vivado installation and see where that leads.

For commercial designs ignoring specifications isn't OK, unless you know how to do it correctly. For self-edifying home projects run on the bench at room temperatures exceeding specifications might work out fine for your needs. If you are pushing the limits of your device I recommend that you use the XADC feature of Series7 devices to monitor temperature and possibly voltages. These are very capable devices that can demand more from the supporting hardware than a board design might provide.

The ZynQ-7020 PL is roughly equivalent to an A75T in terms of performance and resources.  The UltraScale ZYNQ PL performance doesn't tend to scale with the ARM core performance. More homework as the ARM equipped FPGA devices are supported by Xilinx differently in terms of documentation. I tend to think of ZYNQ as an ARM with embedded programmable logic.

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It's clear that this cannot be "sufficiently safe" for a commercial design, even considering that the high clock is going into the OSERDESE2. It would be great to hear an "official" answer from Digilent. It's also obvious that clocks in this board are some sort of limited by size/cost/application.Also It's worth to note that the OSERDESE2 implementation is using DDR, that's a pretty neat trick to get the objective frequencies, especially considering the serial clock.

Most of this pricepoint boards can't even get 720p running with standard timings. This board struggles to get it, bug it gets, and for most developers it's just enough to develop the rest of the system.

This is a good enough board for the price, and does not rely in jerry-rigged designs or obscure files. I have did lots of high bandwidth stuff just with RTL and board files are quite simple. I'm cleaning the bd to get it on github to upload it and discuss it.

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One thing about video, at least for hobby projects, is that a few lost bits here and there, might not result in terrible video performance. You may not notice a few off-color pixels or effects from timing issues. In general video can be pretty forgiving of implementation problems. All of this changes when you have to do commercial or broadcast level video testing and have a product with guaranteed specifications. This isn't  the case for most FPGA applications. A few lost bits every couple of microseconds is likely to be untenable. That's why I generally am willing to make a higher investment in hardware when I know that it will have to support a wide range of projects. I use both the Nexys Video and the Genesys2 for a wide range of applications. They aren't in the same class; but they certainly don't cost the same either. But I've gotten good use out of both of those boards so I'm a happy camper. You mileage, as they say, can vary.  Or as the broadband carriers who've been spending federal grant money to prevent widespread broadband infrastructure say in the weekly mailings that I get: Gigabit Internet only $xx/mo! That's the large print. In the teeny tiny fine print hidden in a dark background is: "XXX makes no representation related to download or upload speeds." To an extent that's the kind of environment that FPGA development boards operate in. At least with FPGA boards you can find relevant information to give you a chance on making a good purchase decision.  

The Xilinx tools have always supported the Kintex 160T for free... and curiously finding boards that use this device are rare as hen's teeth. In fact do search for any Kintex FPGA board out there and see what you get, and at what price. That's a shame as Kintex and UltraScale Kintex is a great semi-affordable family. But I digress...

Personally, I think that the Genesys2 is pretty remarkable for the price.

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Thanks for all the info, seems that if I want proper timings at 1080p, 60Hz, 24-bit colour I am best just using the ADV7513 (or similar). Considering the IC's are only £14 from RS Components and they are purpose built for the job, it seems going that route is first of all, less headache and second of all, likely to yield superior results. Not to mention the cost saving vs a Genesys 2! Just need to make up a custom PCB so it can interface to the FPGA via the FMC connector, not a big deal.

 

As for the Geneys 2, I cannot justify an extra £600 over the Nexys Video, it's just not worth it, even future projects I have involving FPGA's are likely to require lesser devices than the Nexys Video, probably stuff I can do with my current Basys 3. Maybe in future I can re-visit the Genesys, but not just now.

 

However I might re-visit this topic after I get everything fully functional with my project and have completed boards made up and the project is all but finished. Just to see how well I can make it run without the ADV7513 for my own curiosity.

 

Seems that the Nexys Video should be able to do 720p & 1080i at 60Hz with 24-bit colour without too much hassle, even 1080p 30Hz with 24-bit colour depth should be fine, but getting it up to 1080p, 60Hz & 24-bit colour I think will have her running a bit hot.

 

Thanks for all the info so far, especially that IP core! Really good to have that, but I think the answer as to "how did Digilent do it on their demo" (for anyone who finds this thread in the future) is that if they are indeed outputting 24-bit colour, then the only solution has to be running the FPGA out of spec and effectively over-clock it.

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39 minutes ago, Mario875 said:

Thanks for all the info, seems that if I want proper timings at 1080p, 60Hz, 24-bit colour I am best just using the ADV7513 (or similar). Considering the IC's are only £14 from RS Components and they are purpose built for the job, it seems going that route is first of all, less headache and second of all, likely to yield superior results. Not to mention the cost saving vs a Genesys 2! Just need to make up a custom PCB so it can interface to the FPGA via the FMC connector, not a big deal.

 

As for the Geneys 2, I cannot justify an extra £600 over the Nexys Video, it's just not worth it, even future projects I have involving FPGA's are likely to require lesser devices than the Nexys Video, probably stuff I can do with my current Basys 3. Maybe in future I can re-visit the Genesys, but not just now.

 

However I might re-visit this topic after I get everything fully functional with my project and have completed boards made up and the project is all but finished. Just to see how well I can make it run without the ADV7513 for my own curiosity.

 

Seems that the Nexys Video should be able to do 720p & 1080i at 60Hz with 24-bit colour without too much hassle, even 1080p 30Hz with 24-bit colour depth should be fine, but getting it up to 1080p, 60Hz & 24-bit colour I think will have her running a bit hot.

 

Thanks for all the info so far, especially that IP core! Really good to have that, but I think the answer as to "how did Digilent do it on their demo" (for anyone who finds this thread in the future) is that if they are indeed outputting 24-bit colour, then the only solution has to be running the FPGA out of spec and effectively over-clock it.

I think that this could be a better approach. However, if you want a more clean board you can buy one of those Trenz Electronik SOM's and snap it in a sort of motherboard for your application. With nexys video you can develop the inner parts of the system and then go for the final model with some of those SOM's. This is in the pricey side, but you will end with a more professional "workflow" and a cleaner product. Also SOM's are cheaper than development boards because the absence of connectors and peripherals.

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10 hours ago, coldfiremc said:

I think that this could be a better approach. However, if you want a more clean board you can buy one of those Trenz Electronik SOM's and snap it in a sort of motherboard for your application. With nexys video you can develop the inner parts of the system and then go for the final model with some of those SOM's. This is in the pricey side, but you will end with a more professional "workflow" and a cleaner product. Also SOM's are cheaper than development boards because the absence of connectors and peripherals.

Just had a look at those Trenz Electronik SOM's and I REALLY like the idea of them! Buy a single expansion (carrier) board then simply plug in the FPGA SOM you want to develop on. Or of course you can make your own carrier board if you wanted.

 

I have had a look at the carrier board schematic and it is using an ADV7511 (36-bit device) for converting to HDMI. However there are a few issues with it that do not address the issues on the Nexys Video such as....

 

  • GTP ports of the FPGA SOM on are routed to header pins on the carrier which are used for the CameraLink connector, the HDMI comms are on the same header, but the pins that are used for the HDMI port are just generic IO like the Nexys Video.

 

  • They are using an ADV7511 which made me think about buying their carrier and one of their SOMs as it would save me having to make my own daughter board to connect to the FMC connector, however despite the ADV7511 supporting 36-bit input, only 12-lines are connected to the FPGA, the remaining 24 are tied to ground. As I will be taking in 24-bit RGB it would be easier for me to just output 24-bit RBG to the ADV7513 (a 24-bit variant of the ADV7511) and not have to deal with processing data within the FPGA to try and convert a 24-bit input down to 12-bits which will likely result in a loss of video quality also.

 

So for me to make use of their SOM in development stages at least, I would need to make up my own custom carrier board to suit my needs which is not out of the realms of possibility, but that in itself is not exactly a small task as I have to consider all the power rails, impedance, manufacturing of the board, how to program and interface to the FPGA via Vivado, etc, etc. A lot less hassle to just make a breakout board for the Nexys Video and if I decide to make a custom PCB at the end it will be specific for my project and not a dev board to make the project itself, if you know what I mean.

 

However I do really like their concept of just plug in and go, full flexibility to use the FPGA as you desire with custom carrier boards. If the HDMI port had gone directly to the GTP on the FPGA or even made use of 24 or more inputs on the ADV7511 I would have probably opted to go for that, but as it stands, its the same price as the Nexys video (SOM & carrier) and if anything has less features, such as no display port, no OLED screen, less PMODs, etc.

Edited by Mario875
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I'd caution against trivializing anything that looks like "just plug in and go" in the FPGA development board world. There's a lot of details between the promise and reality. The SYZYGY specification seems to be the best effort toward 'plug and play' that I've seen to date, but there hasn't been much in the way of new SYZYGY pods or carrier boards in the past year with that. There are just too many details to tie up for true 'plug and play' for the FPGA arena.

I've done custom mezzanine boards for FMC and HSMC and it isn't at all trivial or cheap. In fact making one of anything involving a custom design and PCB isn't cheap unless the design is trivial, you mount the parts yourself, and you can panelize small circuits.. and will be using multiple finished boards. That's just my experience.

Anyway, is appears the @Mario875is well on his way to figuring all this out.

You can find an FPGA platform to do almost anything that you want, if you are willing to pay for it. If you have a constrained budget then don't feel bad about having to constrain your design goals. The best plan, if you want to execute a project with specific goals and requirements is to find a platform that already supports it. If you need HDMI 2.1 functionality then there are likely platforms available. Just be aware that just because a particular part appears on a board doesn't mean that you can actually use that part to its full capabilities. External memory like DDR is a typical example of this. Always, asking questions and a bit of spelunking are necessary to avoid buyer's regret.

Edited by zygot
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