I have a breadboard Arduino 328 which was working a few months ago (June or July). When I connect it up now the led flashes but I can't remember what sketch is on it and my attempts to upload a new sketch have failed. I get the message
avrdude: stk500_recv(): programmer is not responding
I have a similar device that I put the bootloader on recently and I have no problem uploading sketches to it.
Is there any way to check the bootloader?