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Altera_Forum's avatar
Altera_Forum
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14 years ago

Starting point for DE1 Board

Hi all,

Recently i have buy the Altera DE1 Board.

My objectif is to make a projects with Nios II F and all the things with a commented source for everyone want to start a project with DE1 and C code with the Eclipse IDE.

After i want to send it to the wiki and here for exemple.

I have succesfully integrated and be able to command the Switch , Key and all Led with Nios II Eclipse.

if someone already want the project and source tell me.

But now i want to add the VGA and i request some help.

so just two question please , i know this forum have several VGA question but i just want to make one starting point project for beginner guys ( like me) who want to start a project.

1) Is it Possible to command the VGA directly with the Nios and Eclipse ( by command the Buffer).

2) I have found the Altera Source Code for the CycloneII_2C35 with the VGA.

i have added in my SOPC the vga controller and the vid_pll for the 40Mhz clock and 800*600 resolution.

i can sucessfuly compile my project in Quartus II and Eclipse too but when i flash it i have no signal in my VGA monitor even with Run as Hardware.

Here is my project and my source code , can you tell where is the error ?

http://sega4ever.power-heberg.com/fpga/de1_nios.rar

Thanks a lot !

15 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    I must need to buy The Microtronix Lancelot Card for doing VGA with DE1 and Nios II ?

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    In your top level module it doesn't seem that anything is connected to the VGA outputs, therefore there can't be any VGA output.

    If you go to system0_inst.v you will see a number of extra ports that you haven't added (B_from_vga_controller etc.)

    First add these ports to your instantiation in DE1_NIOS.v and connect them to the VGA outputs (VGA_R, VGA_G, VGA_B, etc.).
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    You're just creating nets that don't connect anywhere. They're not connected to any pins.

    You need to connect them to the VGA ports defined in your top level module. That is, instead of R, connect it to VGA_R, instead of sync_n, connect to VGA_SYNC_N, etc.

    If you look at your top level module, you can find in the port declarations all the ports you didn't connect to : 

    
////////////////////////    VGA            ////////////////////////////
output            VGA_HS;                    //    VGA H_SYNC
output            VGA_VS;                    //    VGA V_SYNC
output        VGA_R;                   //    VGA Red
output        VGA_G;                     //    VGA Green
output        VGA_B;                   //    VGA Blue
output            VGA_CLK;                //    VGA Clock
output            VGA_BLANK;                //    VGA Blank
output            VGA_SYNC_N;                //    VGA Sync
output            VGA_SYNC_T;                //    VGA Sync
output            VGA_M1;                    //    VGA M1
output            VGA_M2;                    //    VGA M2
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    No actually you don't understand at all.

    Here's what I mean. In the .rar file you've supplied, you did this: 

     // the VGA Controller  
                    .R_from_the_vga_controller(R),
                    .B_from_the_vga_controller(B),
                    .G_from_the_vga_controller(G),
    what it should be is this: 

     // the VGA Controller  
                    .R_from_the_vga_controller(VGA_R),
                    .B_from_the_vga_controller(VGA_B),
                    .G_from_the_vga_controller(VGA_G),
    since those are the names of the outputs you have declared.

    I suggest you try to understand Verilog. What your problem was, is that the outputs of your top level module VGA_R, VGA_B, VGA_G, VGA_HSYNC_N, etc. are assigned physically to VGA, but nothing in your Verilog actually drives these signals, therefore there can't be any signal.
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Quartus send me this error during the compilation :

    Error (10170): Verilog HDL syntax error at DE1_NIOS.v(345) near text "."; expecting ")"

    Error (10112): Ignored design unit "DE1_NIOS" at DE1_NIOS.v(43) due to previous errors

    here is my modification 

    
 // the VGA Controller  
                    .R_from_the_vga_controller(VGA_R),
                    .B_from_the_vga_controller(VGA_B),
                    .G_from_the_vga_controller(VGA_G),
                    .hsync_from_the_vga_controller(VGA_hsync),
                    .vsync_from_the_vga_controller(VGA_vsync),
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    1. Those are syntax errors. You might have deleted a ")".

    2. Please use the name of the outputs declared in your top module. That means, not "VGA_hsync", but it should be "VGA_HS", because that was how it's declared in the top module. Using "VGA_hsync" just creates a net that doesn't connect anywhere.

    3. Remember that in verilog everything is case sensitive. "VGA" is not the same as "vga" or "Vga".

    I suggest you refer to a Verilog tutorial ASAP.
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Ok i have rewrited the DE1_NIOS.v with your indications.

    Thanks for your patience really :oops:.

    So actually here is the state of my two files :

    http://sega4ever.power-heberg.com/fpga/de1%20init.rar

    i think this : 

    
 VGA_M1,                          //    VGA M1
        VGA_M2,                          //    VGA M2
        VGA_SYNC_N,                        //    VGA SYNC N
        VGA_SYNC_T,                        //    VGA SYNC T
        VGA_BLANK,                        //    VGA Blank
        VGA_CLK,
    Are part of the Lancelot card so i can't drive it with Nios II eclipse because i don't have the card attached in my FPGA

    I have commented these lines in my DE1_NIOS.v .

    Just need to drive the VGA with Nios II Eclipse ;)

    The Quartus II compilation works but nothing seems to be initialized when i launch the vga demo with eclipse.

    Can you tell me one more time if my files are correct please ?