lcd-routines in avr-assembler
August 22, 2009
i know that not many of you are programming theit avr mcus in assembler, but i 've got something for those who do:
when i started using lcd displays, i just copy-pated or includet the file "lcr-routines.asm" and used those routines that i found on mikrokontroller.net
I found those routines very helpfoul to start working on lcd-displays.
the other attachment called "lcd_routines_advanced.asm" is something i wrote, based on the existing lcd-routines, but using the srram of the avr as a buffer.
the problem with the "standart" routines is, that it can take a while to execute some cammands, especially the "clear display" command takes it's time.
so instead of sending everything straight into the display, i send it straight to the my buffer.
if you call the "lcd_buffer_out" routine every milisecond and don't send too much into the buffer ( overflows can occur ), you can avoid a wait-loop.
it you want to get into it, start with the lcd-routines.asm
the other file is programmed very sketchy, it works for me, but it is a bit more complicated and has several unsolved issues, such as the buffer overflow
if you happen to speak german, you can get a very nice explanation of everything at http://www.mikrocontroller.net/articles/AVR-Tutorial:_LCD