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Altera_Forum's avatar
Altera_Forum
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13 years ago

[DE1] Making the VGA works with the IP VGA Controller

Hi all,

I have a question about the DE1 Board.

These day i am working on a project with SOPC and Nios II.

My objective is to control DE1 feature directly in C with the Eclispe tools.

Actually i can successfully control Led, Key , Switch , SEG7 , SDRAM and SRAM.

Did Someone have a working exemple for control the VGA with Nios II ?

I have tested with this IP :

http://www.altera.com/support/refdesigns/sys-sol/computing/ref-niosii-vga.html

VGA works but pixel coordinate aren't displayed properly ( picture attachement exemple)

i wanted to display a 5x20 yellow rectangle at X=20 Y=20

Did you can help me to make this good strarting point for everyone want to use a simpliest way to control that Card :)

Thanks a lot

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    Hi all!

    I'm new in DE1 KIT.

    I'm building a SoC that displaying data from SDRAM into he screen through VGA.

    My SoC contents:

    - Nios II

    - On-Chip Memory

    -JTAG-UART

    - System ID

    - SDRAM

    - VGA

    I want to display data from SDRAM to VGA by using DMA for reading data from SDRAM to VGA. My C program write data to SDRAM by NIOS. Then I use DMA to read data from SDRAM to VGA. When the interrupt occur, DMA will read 640 value (1 line) from SDRAM to VGA.

    My VGA core has a FIFO to buffer data. When fifo is empty, the VGA core will make a interrupt signal to control the transferring of DMA.

    My system has some problems such as:

    - First: When I use NIOS II to verify the read, write of SDRAM, it operates unstablely. I use "for" loop to write and read data to SDRAM but it just correct in the first 154 values

    - Second: When the interrupt occur, DMA only operates within two loop, in third loop, DMA reports the error : "Can post request..."

    Anybody can help me. please!

    Thanks so much!