I don’t know how long it will take you to read this but I have just been sent a atmega328p -pu with no bootloader.
I am trying to follow your instructions on Gammon Forum : Electronics : Microprocessors : Atmega bootloader programmer
I have wired 2 uno’s up as per the drawing,
downloaded the zip file you supply on that page (it says version 1.20 at the top but has version 1.21 at the bottom of the list - i think you forgot to update the version number in the title :).).
moved it into a folder and loaded it into one of the uno’s (both are quite new uno’s and I have only recently downloaded the software from the arduino.cc site so I am suspecting they are not compiled under the older version.
I have put the file atmega_board_programmer.ino in its own directory as required and loaded it into the uno with the other files inside the directory and it compiles and loads into the uno
When I open the monitor all I get is
4þ?i’è?uÂ<ÊF6X8?J?©-40¸ \rZ4kÿ??y?k -$P??Ý?@eIU?þ (though it looks slightly different here, a lot of the symbols are square boxes and they are different each time I open the monitor or press reset)
If I press the reset it just gives me another line on the monitor like the one above.
I have removed the wiring and loaded the blink program which works ok so I suspect the uno is ok.
Can you help?
the baud_rate Nick has set in the programme is 115200. I usually use 9600, is there somewhere on my programmer that I need to change this or does the 'Serial.begin' in the programme set this up
I have changed the baud rate in the programme to 9600 and it looks as if it is working. I got straight back here to say so without checking it so I will be a few minutes seeing if the programme now works.
thats better. It didn't quite work as described in the page http://www.gammon.com.au/forum/?id=11635 I didn't get the example output, I got the box below it with 'Type 'C' when ready to continue with another chip ...' I assumed the job had been done and it failed to load the blink prog' to test it but when I tried a second time I pressed 'c' and got 'Type 'L' to use Lilypad (8 MHz) loader, or 'U' for Uno (16 MHz) loader ...' at the bottom, when I pressed 'U' I got the line at the bottom of the example output to press 'G' to program the chip. If you read this Nick thanks for putting that up, a chip purchased from e-bay saying it had the bootloader on was useless to me without your help. Thanks spycatcher, do I have somewhere on my programmer that I enter a required baud rate as I can't find it?
If I put the baud_rate (that's how it's assigned as a variable in Nicks sketch) to 115200 I get the mixed symbols but at 9600 it's fine?