I use an amateur radio transmitter by QRP Labs called a U3S that comes with a pre programmed Atmega328P processor. The kit has the option of adding a 6 pin header to allow in circuit programming. I took this option and extended it to an RS232 port on the rear. Using a cheap Ebay USBasp I can read a pre programmed chip, and I can update its firmware successfully.
I bought, from RS Components, some new, seemingly genuine ATMEL 328 PU chips. If I install one in place of a pre programmed chip, the programmer cannot even see it. I have tried three fairly similar cheap programmers, all of which see and read / write pre programmed 328 chips just fine, but none see the new ones.
I have tried Extreme Burner and a Chinese app called progisp1.72 Neither software sees the new chips, but otherwise work with "factory" ones I am reliably informed there's no reason NOT to be able to write supplied code to a new chip, and others have successfully done just that.
. I am going to try AVRdude with AVRdudess GUI in a bit, but fear the worst as I suspect I am missing something. To be brutally honest the technicalities of all this are not of huge interest, I just want to write some spare chips to new 328 PU's :) How hard can this task be? ;) Can anyone kindly and simply explain what my issue may be please? Thanks and a happy and healthy New Year to all.