Dual RAM and Analog Output

Showcase builds, discuss cases, embedding MiSTer into existing computer cases.
AmintaMister
Posts: 313
Joined: Thu Sep 16, 2021 10:54 pm
Has thanked: 841 times
Been thanked: 51 times

Dual RAM and Analog Output

Unread post by AmintaMister »

Hi there, some hardware-related MiSTer Fpga things are not clear to me:

1) why we can't use DualRam together with analog output with new boards like this?

2) what is exactly the A/V module?

3) the new 24 Bit ADV Video DAC is possible only with analog output or also with the digital one?

Thanks in advance for you answers!

Hetzen
Posts: 147
Joined: Thu Oct 14, 2021 1:55 pm
Has thanked: 77 times
Been thanked: 45 times

Re: Dual RAM and Analog Output

Unread post by Hetzen »

I believe it's because the DE-10 Nano has two strips of i/o pins that can be used for 2xRAM modules OR 1xRAM module and 1xAnalogue video conversion.

The ADC is what converts digital values to an analogue voltage curve that mimics the analogue video requirements of older CRT monitors. It has no effect through HDMI. HDMI's data stream is digital, so no need for conversion. Bottom line is, if you're not going to use a CRT, then you don't need it, and use the i/o pins for an extra RAM module.

AngelicLiver
Top Contributor
Posts: 434
Joined: Fri May 29, 2020 8:50 am
Has thanked: 86 times
Been thanked: 120 times

Re: DualRam and analog output

Unread post by AngelicLiver »

  1. Limited GPIO pins on the DE10-Nano. If you are using the second GPIO headers for SDRAM you can't use the analog IO board.

  2. It's an addon board for analog IO boards to output 24-bit video via the VGA port using a DAC.

  3. 24-bit DAC is for analog video output only. The digital IO boards do not have analog video out. HDMI isn't affected.

You can still use analogue video with dual SDRAM but you'll need to use direct video.

AmintaMister
Posts: 313
Joined: Thu Sep 16, 2021 10:54 pm
Has thanked: 841 times
Been thanked: 51 times

Re: DualRam and analog output

Unread post by AmintaMister »

AngelicLiver wrote: Thu Nov 14, 2024 8:01 pm
  1. Limited GPIO pins on the DE10-Nano. If you are using the second GPIO headers for SDRAM you can't use the analog IO board.

  2. It's an addon board for analog IO boards to output 24-bit video via the VGA port using a DAC.

  3. 24-bit DAC is for analog video output only. The digital IO boards do not have analog video out. HDMI isn't affected.

You can still use analogue video with dual SDRAM but you'll need to use direct video.

Thanks! So via Direct Video I can't achieve 24 bit video?

User avatar
dickhardpill
Posts: 292
Joined: Tue Apr 09, 2024 9:28 pm
Location: Not Portland, OR
Has thanked: 74 times
Been thanked: 60 times
Contact:

Re: DualRam and analog output

Unread post by dickhardpill »

AmintaMister wrote: Thu Nov 14, 2024 10:24 pm

Thanks! So via Direct Video I can't achieve 24 bit video?

24-bit is achievable via DV

1 I believe you can use direct video and HDMI to VGA to get 24-bit analog out and dual RAM
2 the AV module is what turns the IO 9.2 baseboard (which is a digital IO board) into an analog IO board
3 From what I understand 24-bit has been available via HDMI for longer than analog as it wasn't available until the 9.2 board

User avatar
LamerDeluxe
Top Contributor
Posts: 1239
Joined: Sun May 24, 2020 10:25 pm
Has thanked: 887 times
Been thanked: 284 times

Re: Dual RAM and Analog Output

Unread post by LamerDeluxe »

One thing is that HDMI to VGA adapters vary a lot in the quality of their output colors. There's a whole thread about it here somewhere.

User avatar
dickhardpill
Posts: 292
Joined: Tue Apr 09, 2024 9:28 pm
Location: Not Portland, OR
Has thanked: 74 times
Been thanked: 60 times
Contact:

Re: Dual RAM and Analog Output

Unread post by dickhardpill »

LamerDeluxe wrote: Fri Nov 15, 2024 8:11 am

One thing is that HDMI to VGA adapters vary a lot in the quality of their output colors. There's a whole thread about it here somewhere.

I’m definitely looking forward to the Reflex Prism

User avatar
LamerDeluxe
Top Contributor
Posts: 1239
Joined: Sun May 24, 2020 10:25 pm
Has thanked: 887 times
Been thanked: 284 times

Re: Dual RAM and Analog Output

Unread post by LamerDeluxe »

dickhardpill wrote: Fri Nov 15, 2024 10:14 am
LamerDeluxe wrote: Fri Nov 15, 2024 8:11 am

One thing is that HDMI to VGA adapters vary a lot in the quality of their output colors. There's a whole thread about it here somewhere.

I’m definitely looking forward to the Reflex Prism

That looks like a good solution, hadn't heard about it yet.

lloydsmart
Posts: 16
Joined: Thu Oct 17, 2024 3:38 pm
Location: UK
Has thanked: 2 times
Been thanked: 3 times

Re: Dual RAM and Analog Output

Unread post by lloydsmart »

I may be mistaken, but I believe the point of the new AV Pro board is that it utilises Direct Video, and is therefore compatible with dual RAM while maintaining analogue output at 24-bit colour depth.

The one and only trade-off is that you can't have simultaneous HDMI and analogue output, which could be important for streamers who need to capture via HDMI while playing via analogue. Unless this applies to you, I reckon this new AV Pro board is the absolute best solution for analogue output at the moment.

Can someone with more knowledge than me confirm that this new board does in fact work via Direct Video? And that therefore it is compatible with dual RAM whilst giving a high quality analogue output? Cause that's how it seems to me.

FoxbatStargazer
Top Contributor
Posts: 1019
Joined: Thu Dec 10, 2020 5:44 pm
Has thanked: 315 times
Been thanked: 238 times

Re: Dual RAM and Analog Output

Unread post by FoxbatStargazer »

lloydsmart wrote: Mon Nov 25, 2024 2:29 pm

I may be mistaken, but I believe the point of the new AV Pro board is that it utilises Direct Video, and is therefore compatible with dual RAM while maintaining analogue output at 24-bit colour depth.

The one and only trade-off is that you can't have simultaneous HDMI and analogue output, which could be important for streamers who need to capture via HDMI while playing via analogue. Unless this applies to you, I reckon this new AV Pro board is the absolute best solution for analogue output at the moment.

Can someone with more knowledge than me confirm that this new board does in fact work via Direct Video? And that therefore it is compatible with dual RAM whilst giving a high quality analogue output? Cause that's how it seems to me.

Unfortunately there are several varieties of "pro" board out there now so you have to be more specific.

The new official standard 9.2 analog i/o board doesn't use direct video at all, its coming over the GPIO pins like the prior ones. There is a mezzaine that connects the top of the board to the VGA port, you can remove this and stick dual ram in its place I think, so its a very manual process to switch between dual ram and analog out functionality.

Misteraddons makes something called "IO direct" which does feed direct video hdmi out from the De/10 nano back into its own DAC via an HDMI in. And I think a few other sellers are doing something similar. But these are different from the official 9.2 board.

Post Reply