ZPUino_GFX - no sync possible at 60Hz


monsonite

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Hi Jack, Alvie,

 

This is probably a monitor related problem, but I cannot get any video displayed from the ZPUino_GFX demo sketches.

 

My monitor seems to default to a 800 x 600 72Hz frame rate, regardless of the vertical timing sent from ZPUino_GFX

 

It locked perfectly with the old VGA examples - which were 160x120.

 

Is there an easy way to modify ZPUino_GFX.cpp  const modeline_t to achieve a 72Hz sync?

 

If not - I'll try some other monitors.later this week

 

BTW - Alvie and I had an enjoyable meet-up at the London Hackspace last Tuesday.  We hope to stir up some Papilio Duo interest there.

 

 

regards

 

 

 

Ken

 

London

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Jack, Alvie

 

I have now put a scope on the HSYNC and VSYNC and can confirm that the GFX_Demo sketch is producing a 72.118Hz Vsync and a 48.037Hz Hsync.

 

There does not appear to be any video present on any of the R-2R resistor network - so the monitor is permanently blanked.

 

Is there something else that needs to be configured to obtain video out, other than just loading the demo sketch?

 

My set-up is a 2MB Papilio Duo with a LogicStart shield.

 

 

Thanks in advance

 

 

 

Ken

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Hello Ken,

 

Are you uncommenting the circuit for the DUO and the Logicstart Shield?

 

By default it is set to work with the Computing Shield on the DUO

//Uncomment to use with a Computing Shield on Papilio DUO#define circuit Computing_Shield2//Uncomment to use with a LogicStart Shield on Papilio DUO//#define circuit LogicStart_Shield2//Uncomment to use with a Arcade MegaWing on Papilio Pro//#define circuit Arcade_MegaWing2//Uncomment to use with a LogicStart MegaWing on Papilio Pro//#define circuit LogicStart_MegaWing2//Uncomment to use with a VGA Wing connected to AH Wingslot on Papilio DUO and Papilio Pro//#define circuit ZPUino_Wings

You need to change it to this:

//Uncomment to use with a Computing Shield on Papilio DUO//#define circuit Computing_Shield2//Uncomment to use with a LogicStart Shield on Papilio DUO#define circuit LogicStart_Shield2//Uncomment to use with a Arcade MegaWing on Papilio Pro//#define circuit Arcade_MegaWing2//Uncomment to use with a LogicStart MegaWing on Papilio Pro//#define circuit LogicStart_MegaWing2//Uncomment to use with a VGA Wing connected to AH Wingslot on Papilio DUO and Papilio Pro//#define circuit ZPUino_Wings
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Hi Jack,

 

Yes - that's all commented to suit the Duo with LogicStart.

 

I've also gone down to about line 56, and uncommented the minimum resolution -    

 gfx.begin( &modeline_320x240_60 );

But still not seeing any activity on any of the RGB bit lines.

 

The ZpUino is happily working through the demo - printing to the serial terminal window as it progresses. However, no video.

Benchmark                Time (microseconds)Screen fill              39Text                     1885Lines                    34Horiz/Vert Lines         36Rectangles (outline)     38Rectangles (filled)      0Circles (filled)         34Circles (outline)        166Triangles (outline)      33Triangles (filled)       0Rounded rects (outline)  36Rounded rects (filled)   34Done!

I have tried the ZPUino_GFX gfxdemo  (the last on the list of examples with DesignLab 1.05) and the results are similar - 72Hz/48kHz syncs are present but no video.

 

 

regards

 

 

 

Ken

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Ok, 

 

Just to be double sure, after you uncomment the following line:

//Uncomment to use with a LogicStart Shield on Papilio DUO#define circuit LogicStart_Shield2

You are clicking on the "Load Circuit" icon to load that circuit to the FPGA?

 

I'll double check here to make sure that the DUO and LogicStart Shield are working.

 

Jack.

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Jack, Alvie

 

Thanks for your help.

 

Now that I have 800 x 600 running, I can now start to play with my CAD ideas.  This will be a great boost - thanks.

 

BTW - I notice from Github that James Bowman is porting his J1 Forth processor to the Papilio DUO - with several changes to manage the byte wide RAM.

 

https://github.com/jamesbowman/j1/blob/master/verilog/j1.v  - changes in the last couple of days

 

Onward and upwards

 

Ken

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Hey Jack,

 

I saw James speak about GameDuino at the OSH conference in NYC in Sept 2011.

 

I am really looking forward to getting down to machine code level with the J1. I first used Forth in '83 on a Z80.

 

Spent this evening updating the CAD primitives so they display with the gfx library at 800x600.

 

This could be a lot of "vintage" fun but with ZPUino powering it along at 96MHz.

 

 

best

 

Ken

 

London

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