Just trying to figure out some weird bug I've been having that's re-occurring between designs. It's the elusive 0xC0 error. It usually occurs mid-development of a system and it's really starting to rustle my jimmies. One of my friends was able to solve the error by forcing avrdude to re-write the default fuse bits (they were never touched during development). I can't figure out if this is a software issue or a hardware issue but it's popped up on three different board designs. I have decoupling caps on all of my power pins and I'm running with the internal oscillator. All of my devices on the spi bus are pulled into shutdown via 10k pullup/down resistors so it's not other devices trying to talk over the chip. Any hints? My solutions in the past have been to desolder the 328p and drop in a fresh one. Like I mentioned previously, this occurs mid-development so the chips I put into the system are fine and functional to start with. I've attached the error message.
The only thing that changed from the last time I programmed to this time was me connecting the negative terminal of my power supply to ground.
Some things I've tried:
Power cycling the chip (AVRISPMKII behaves as expected)
Reducing the clock speed
Restarting my system
Checking the voltage on the MKII (obviously this can be done without talking to the chip)
Things I cannot do:
Read the device ID, FUSES, Security bits, erase chip.
OS: Windows 10 (gag)
Programmer: AVRISPMKII ("Good" internal Green LED is ON so my connection isn't bad)
Voltage: 4.9V (Far above the BOD options)
Also: What does the Green LED even mean? Is it just checking that power is applied to the correct pin? Is it actually trying to check for a device on the SPI bus?
EDIT! APPLYING SIGNIFICANT PRESSURE TO MY CONNECTOR (PRESS FIT IN PLACE) MUST HAVE SET A BAD CONNECTION. I'll just solder this thing in and desolder when I'm done. My question now is why is the device replying with 0xC0 consistently even when the connection is bad?