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Altera_Forum
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21 years ago

Modifying Nios II Device Drivers?

Hello all... I would like to create a new version of the altera_avalon_lcd_16207 device driver. I have a 20 character x 4 line display that I would like to use instead of the 16 character x 2 l...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
21 years ago

Hello Goon,

If I get a chance I'll try your suggestion. For right now I just hacked the existing driver to make it work.

Just in case anyone wants to do the same here is what I did to support the 20x4 LCD.

In the altera_avalon_lcd_16207\HAL\inc\altera_avalon_lcd_16207.h file change the ALT_LCD_HEIGHT and ALT_LCD_WIDTH# defines to match the actual LCD size. In my case the height is 4 and the width is 20.

In the altera_avalon_lcd_16207\HAL\src\altera_avalon_lcd_16207.c file change the static char colstart[4] values to match the memory addressing for each line of the display. THis information should be found in the datasheet for the display you are using. On the Opterx DMC20481 display I am using these values are 0x00, 0x40, 0x14, 0x54.

I looked over the rest of the HAL code for the LCD and everything else works without changing anything. The display still scrolls long lines (any line over ALT_LCD_WIDTH up to ALT_LCD_VIRTUAL_WIDTH) and it scrolls up as it's supposed to when lines are added to the bottom of the display.

Thanks for the reply.