Hello! For some reason when I compile this code, the output is 10.0 KB and I have no idea why... I'm using the latest version of WinAVR for my ATTiny45V.
When I comment out "else length++;", the file size becomes 345 bytes. Could someone please help?
#include#include int main(void) { DDRB |= 1<<PB3; DDRB |= 1<<PB4; double length = 1.0; while(1) { PORTB &= ~(1<<PB3); _delay_us(length); PORTB |= 1<<PB3; _delay_us(length); if(length > 1000.0) length = 0.0; else length++; } return 0; }
Must you use floating point maths?
I actually just switched it to double after reading the avr libc documentation (http://www.nongnu.org/avr-libc/user-manual/group__util__delay.html). I thought it would be best to keep the variable types the same, but it was still doing it before when I was trying 16 and 8 bit ints.
You should read the documentation you linked to again. Particularly this:
In order for these functions to work as intended, compiler optimizations must be enabled, and the delay time must be an expression that is a known constant at compile-time. If these requirements are not met, the resulting delay will be much longer (and basically unpredictable), and applications that otherwise do not use floating-point calculations will experience severe code bloat by the floating-point library routines linked into the application.
i think that you can configure the linker in the way that it links libraries statically not dynamically , i am not sure that this will works , it works great with AVR32 linker.
And ofcourse use an optiminization level like -O2
i think that you can configure the linker in the way that it links libraries statically not dynamically...
The basic problem with the increase of programs using a dynamic delay time comes from the folating point math. I think it was discussed here. The out come of the discussion was call the delay routine with a static value and make a loop around or in case you hae a spare timer and need precise timing use a timer.
OS ??? , i think that you are talkin about uC architecture .
The basic idea is that the linker assign all stuff (useful and unuseful) of a library to the project this is dynamically, but when it s assigned statically , it will only link the used 'parts' of a library in the project, and that helps to reduce size .
Well as i said i am not sure that this will work , it s just a try/suggestion ;)
The basic idea is that the linker assign all stuff (useful and unuseful) of a library to the project this is dynamically,...
...but when it s assigned statically , it will only link the used 'parts' of a library in the project, and that helps to reduce size .
