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greengun

Can Arty Z7 handle 4k60p hdmi?

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I bought an Arty A7. Somewhat by mistake I have to admit as I must have overlooked the Z7, which seems more suitable fow what I want to do.

 

i want to take a 4k60p hdmi signal, invert all color values and output the signal with sub-frame latency.

 

with my A7 i managed to get this to work with 1080p@60 using improvised PMOD to HDMI adapters, but I don’t manage to get 4k60 to work.

Now I wonder whether I should buy the Z7 or if neither of these boards is capable of doing that anyway.

 

did someone get 4k60 hdmi to work with either board?

 

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What do you mean by 'handle'?

The FPGA fabric could process the video stream, but unless the FPGA transceivers are connected to the HDMI sockets it won't be able to. On the Z7 the HDMI connectors are on the standard I/O pins. 

Also, HDMI 2.0 is required for that video rate, and the spec isn't openly published. 

 

 

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So, does that mean no?

 

in particular, are you saying that on the Arty Z7 the hdmi ports are not connected to the transceivers? So would I have better chances to succeed with the A7 and PMOD to HDMI adapters?

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None of these options will deliver 2160p.

To do 2160p (and even 1080p) you need hardware specifically engineered for that purpose, not a generic multipurpose development board. 

The only Digilent board that I am pretty sure could support a 2160p 60hz display is the Gensys2, using the DisplayPort interface. However event that might be restricted to 422 YCC formats (not 444 RGB) 0

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8 hours ago, hamster said:

The only Digilent board that I am pretty sure could support a 2160p 60hz display is the Gensys2, using the DisplayPort interface. However event that might be restricted to 422 YCC formats (not 444 RGB) 0

It's got four 10.3125 Gbps lanes connected to DP connectors, that allows implementing up to DP 2.0 UHBR 10, 40 Gbps, which is good for up to 8K@30Hz or 4K@144Hz in 444 RGB mode: https://en.wikipedia.org/wiki/DisplayPort#Refresh_frequency_limits_for_standard_video

But that is going to require getting your hands on DisplayPort 2.0 specification, which requires paying $5000 or $10000 a year depending on a size of your company :( These greedy lawyers drive me nuts!

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2 minutes ago, asmi said:

It's got four 10.3125 Gbps lanes connected to DP connectors, that allows implementing up to DP 2.0 UHBR 10, 40 Gbps,

Have you actually driven or received 40 Gbps data on the Genesys2? That would be interesting.

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41 minutes ago, zygot said:

Have you actually driven or received 40 Gbps data on the Genesys2? That would be interesting.

Not yet as I'm busy with another project, but definitely will at some point!

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51 minutes ago, asmi said:

Not yet as I'm busy with another project, but definitely will at some point!

I understand being busy.

A while ago I posted an Aurora implementation for the Genesys2 looping the DP out back into the DP in on one board using 10.8 Gbps (4x 2.7). I suspect that the board will support twice that rate, though I haven't tried. I'd be thrilled to have someone post a similar project that i can replicate doing almost 4x this data rate; though I don't have cables claiming to support over 40 Gbps. Doing this between two Genesys2 boards would be pretty exciting indeed; especially for a board that only claims to do DisplayPort 1.1 link rates. I do love nice surprises!

The ZCU106 board was designed to support 12G_SDI video but trying to replicate the TRD is, well, challenging.

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1 hour ago, greengun said:

The XCA75T has 8 6.6 Gb/s transceivers. Shouldn’t that be enough for 4k60 in and out?

Let's assume that what you report is absolutely true for all speed grades. Inferring capability based on one specification is a very very bad analysis. Ignoring board design and implementation factors is just crazy. Assumptions are never a reasonable replacement for homework.

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5 hours ago, zygot said:

Have you actually driven or received 40 Gbps data on the Genesys2? That would be interesting.

I've done a total of 10.3125 Gbps, or maybe 10.8 GB/s over the four lanes... can't remember if it is 2.7Gb/s or 2.65 Gb/s per lane. It was a while ago...

That is just enough for 4k60.

Edited by hamster

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2 hours ago, greengun said:

@hamster why would neither work? The XCA75T has 8 6.6 Gb/s transceivers. Shouldn’t that be enough for 4k60 in and out? (4 transceivers each, one for each tmds pair).

 

There is also this: https://www.xilinx.com/products/intellectual-property/hdmi.html shouldn’t that work on the Arty A7?

The transceivers are on dedicated pins, and are seldom connected to the HDMI sockets unless the board was expressly designed for video.

As mentioned earlier, this isn't a restriction of the FPGA - the FPGA can handle this data rate. It is a restriction imposed by choices made by the development board's designers.

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But two of the PMods of the Arty A7 are on the highspeed pins (I assume that means the transceivers), so shouldn’t I just be able to output my hdmi signal there (the way I already do it successfully with 1080p)

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The PMOD Specification res 1.2 mentions 25MHz for low speed ports, and 100MHz for the high speed ports. 

I have managed to get 400Mb/s through them once (for HDMI RX). But that is only enough for 800x600.

 

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1 hour ago, hamster said:

The PMOD Specification res 1.2 mentions 25MHz for low speed ports, and 100MHz for the high speed ports. 

I have managed to get 400Mb/s through them once (for HDMI RX). But that is only enough for 800x600.

 

Well I did get 1080p60 out to work so at least that they seem to be able to handle.

Does that mean the transceiver pins are not broken out on the Arty A7?

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