FPGA, SoC, And CPLD Boards And Kits
FPGA Evaluation and Development Kits
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[DE1] Making the VGA works with the IP VGA Controller

Honored Contributor II

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 : 



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
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1 Reply
Honored Contributor II

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 


- System ID 


- 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!
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