Intel® FPGA University Program
University Program Material, Education Boards, and Laboratory Exercises
Announcements
Intel Support hours are Monday-Fridays, 8am-5pm PST, except Holidays. Thanks to our community members who provide support during our down time or before we get to your questions. We appreciate you!

Need Forum Guidance? Click here
Search our FPGA Knowledge Articles here.

Char Buffer UP IP

Altera_Forum
Honored Contributor I
801 Views

Hi  

 

I'm trying to realize a text terminal on VGA display using Char buffer and VGA control available in UP IP v9.0 

I've implemented the Nios on a DE1 board. 

 

 

I'm sure that the hardware works properly, since writing a value directly on the mem position, a char appear on the VGA monitor 

 

But I've some problem to write a suitable software. 

 

I tried with: 

 

 

int 

main() { 

 

int i; 

alt_up_char_buffer_dev * my_ch_buf; 

 

 

printf( "Nios II Alive!\n\n" ); 

 

 

my_ch_buf = alt_up_char_buffer_open_dev( "/dev/character_buffer_0_avalon_char_buffer_slave"); 

 

if ( my_ch_buf == NULL) 

alt_printf ("Error: could not open pixel buffer device \n"); 

else 

alt_printf ("Opened pixel buffer device \n"); 

 

i = alt_up_char_buffer_draw(my_ch_buf , 'A', 30,30); 

printf( "res=%d",i ); 

 

 

but the answer is :( "Error: could not open pixel buffer device": infact the function "alt_up_char_buffer_open_dev" does not open the device and so the subcessive function "alt_up_char_buffer_draw" is unable to write anything. 

 

Any suggestion? 

Is maybe available some C examples using this device ? 

 

Thank you in advance 

 

Stefano 

 

 

 

 

 

 

 

 

 

0 Kudos
1 Reply
Altera_Forum
Honored Contributor I
75 Views

OK, I solved the problem by myself: 

 

The correct neme of the device was: 

 

"/dev/character_buffer_0"; 

instead of 

"/dev/character_buffer_0_avalon_char_buffer_slave"; 

 

Whoever it is not clear for me where the "name" of the device is assigned 

i.e. where to find the correct name  

 

in the first release I used the name found in "system.h" which was of course wrong.
Reply