avr_fred:
Seriously, what does any of this have to do with a board detector program?
well, for one thing, it is the ONE resource that i know is reliable.
i don't understand how that sketch works, so i have been giving (maybe too much) information of all the various scenarios that i have encountered, in the hope that it helps show what is going on.
avr_fred:
All that I can tell from your post is that you probably don't have a current Uno bootloader installed because if you did, the hfuse should be 0xDE which says the bootloader is 256 bytes in size. 0xDA says yours is 1024 bytes.
OK, i'm out of my depth here - on Nick Gammon's page, i see in an example, it was 0xDA but now i understand it was 512 bytes for a Lilypad bootloader.
avr_fred:
So you're telling me you haven't uploaded a bootloader to this chip? If not, you have absolutely no idea of what that chip looks like to avrdude, other than the device signature.
Edit:
Don't bother with fuses, just burn the bootloader, the IDE takes care of the fuses.
i have not uploaded a bootloader because i have never had to because it was the original chip that came with the UNO board and i have been using it for years in-situ, uploading sketches to it.
now - i have swapped it with a newer chip (reason in that other thread) - and i didn't think i would still need to burn a bootloader on it - that Board_Detector sketch confirmed it - it HAS the bootloader;
i would rather NOT burn another bootloader AGAIN - not knowing if the programmer chip being a 328_ will make a difference - that 328P is the original chip and i don't want to mess with it (i was even averse to removing it from the board in the first place.)
i HAVE burned a new bootloader onto the 328_ chip, AND successfully ISCP'ed a sketch onto it - but then, using the CH340G, it would not upload a NEW sketch onto it.
EDIT:
i guess that's because, being ICSP'd - the bootloader got erased.
but that is NOT the case with the 328P now - because it was loaded BY the UNO board.
SO; i will now SWAP the chips again - the original 328P back on the UNO, and the new 328_ on the breadboard (WITH bootloader), and i will print the result of the Board_Detector with the complete info, signature and fuses.
and then i will be willing to do whatever you suggest to that 328_, given the condition at that moment.
thanks for your patience in helping me with this odd situation.