I'm aiming at building my own programmer and programming my ICSP capable microcontrollers from my PC. It would be both an opportunity to learn and maybe save me from buying my own programmer
I was wondering however if anyone knows about circuits implementing this functionality already trough USB or a Serial interface. And perhaps open source software for writing the data into the microcontroller. Finding software examples for writing into serial/usb ports shouldnt be a proplem though.

Seeing some example circuits would save me alot of design time, since developing it from scratch might require more time. I've tried searching for circuits on the net but they seem to be hard to find. Since it's propably easiest to just buy a programmer but as mentioned earlier i'm trying to avoid that.

Any feedback and suggestions are appreciated

 

Take a look at the 89C5131 from Atmel. No programmer needed. Hook it up directly to the USB of your PC and download the hex code using the free software from Atmel.

 

I'm mostly programming PICs so i'm def gonna need a programmer.

I've found some serial/parallel port circuits for programming pics but i'm gonna build a USB one.

 

Try a google search for "PICKit2 clone".

 

An also download the PICkit2 user manual. The schematic is available there.