Hi all, I designed a barebones board for the Atmega2560 (oscillator, caps, reset resistor, power supply) and am having trouble programming a bootloader onto it.
Pretty sure the problem is with the programmer but I wanted to also do as much testing as possible on the barebones board just in case.
So far I have made sure there is continuity between the ground and power lines, that all the decoupling capacitors are soldered correctly, the power supply is outputting correctly and the TMS/TMK pins are showing a high voltage.
The board is taking 20-30mA or so and upon shorting the reset to ground I get a dip in current draw.
I was wondering if there are any other tests that would work on a board/chip that has not been flashed/fuses changed?
Would a factory fresh Atmega2560 be utilizing the external crystal? Could I test the crystal with an oscilloscope or would it only oscillate once the fuses are changed? If it is using an internal oscillator from the factory, could I test to see if it was running or will the chip be in a passive state fresh from the factory?
Any advice would be greatly appreciated.