My project seemed simple:
I have a breakout board for atmega328p (tqfp). I'm using a 16MHz oscillator with the prerequisite 16pF caps. I'm connecting only the 6 pins from the programmer.
I'm using Arduino SW 1.8.8 using the usbtiny programmer from Sparkfun.
I set the board to Arduino Pro, or Pro Mini.
I made 4 boards. 3 of them I get the response "avrdude: Device signature = 0x000000"
one of them gets "avrdude: Device signature = 0xffffff"
I beeped them all, no accidental connections to GND or VCC.
I also tried using a simple ceramic oscillator, as well as no external oscillator. No difference.
The chips are from Digikey, not eBay. They're ATMEGA328P-AURCT-ND
The programmer works, I can program the same chip on a redboard.
I've done the same thing years ago without any problems. What the blazes am I doing wrong?