How can I get a VGA signal in addition to HDMI?

[jmio]

Hi,

I am continuing to learn SaxonSoc's Minimal sample. I've got VGA (HDMI) from SDRAM working. I want to output to HDMI, but also externally extract the VGA signal for LCD.

I think SaxonSoC automatically creates the inputs and outputs with InOutWrapper. In this case, how should I describe it?

ICESugarProMinimal.scala

[Dolu1990]

Hi,

I guess below : https://github.com/jmio/SaxonSoc/blob/vga_dma/hardware/scala/saxon/board/muselab/ICESugerPro/ICESugarProMinimal.scala#L170

val vgaPhy = vga.withRegisterPhy(withColorEn = false)

should be good ?

[jmio]

Oh! It worked. Thank you very much(^^)

I've read up on withRegisterPhy(), but I'm still not sure how it works. I want to take the internal signal (VgaCtrl.io.xxxx) out to create a text screen overlay.

I know it's not a good way to do it, but I can't do it in Spinal yet, so I want to do it in Verilog(^^;

In this case, how can I get the signal from BmbVgaCtrl.io and then bring it to the top level?

[Dolu1990]

ahhh Then

val vgaBus = Handle(vga.output.toIo) 

should be fine ?

[jmio]

It worked like magic !

I would like to know what kind of rules make it work this way. Is there any code that can help me understand it?

[Dolu1990]

I would like to know what kind of rules make it work this way.

So, SaxonSoc is kind of a paradigme on the top of SpinalHDL, it use the fiber stuff to specify things in a "distributed" manner : https://spinalhdl.github.io/SpinalDoc-RTD/master/SpinalHDL/Libraries/fiber.html

Basicaly, Handle{ ... } fork a new thread to execute the given chunk of code, which can do active blocking when one of the thing it try to access isn't generated yet.

Then the "toIo" is a regular SpinalHDL thing to propagate io from a child component to the parent component.

Is there any code that can help me understand it?

Hmmm, the whole SaxonSoc stuff ^^ I mean, in general, be sure to have a proper IDE to explore the code, it reaaaaly help, me i'm on intellij.

[jmio]

Thank you for your answer.

I managed to learn "toIo" (^^; I'll also try Intellij IDE.

I pull out the VgaCtrl.vga.ctrl.io.frameStart using "toIo", saw the following error

[error] HIERARCHY VIOLATION, (toplevel/system_vga_logic/vga_ctrl/io_frameStart : out Bool) can't be used in toplevel at
[error]     saxon.board.muselab.ICESugarPro.ICESugarProMinimal$$anonfun$6$$anon$5$$anonfun$8.apply(ICESugarProMinimal.scala:223)
[error]     saxon.board.muselab.ICESugarPro.ICESugarProMinimal$$anonfun$6$$anon$5$$anonfun$8.apply(ICESugarProMinimal.scala:223)
[error]     spinal.sim.JvmThread.run(SimManager.scala:51)

I was able to get "frameStart" out, but... So, I ended up copying the definitions of the three classes in their entirety.

(https://github.com/jmio/SaxonSoc/commit/35020f543fc0ef24e3281d92a7a02cdaf82b35d0#diff-b9270f6802cfabf0bd12a5a10a5754fa879eb61bc5551fcdd28310c206e47331)

I guess I need to learn Scala properly (^^;

[Dolu1990]

Ahhh if you go more than one level deep into the hearchy, you have to do a :

VgaCtrl.vga.ctrl.io.frameStart.pull().toIo

That should work, as long that everything pulled is just for read (not for write) ^^

[jmio]

pull().toIo is handy (^^)