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Char Buffer UP IP

Honored Contributor I



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: 




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"); 


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 












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1 Reply
Honored Contributor I

OK, I solved the problem by myself: 


The correct neme of the device was: 



instead of 



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.