I am trying to upload code to that circuit, but it won't upload.
Any ideas?? Tried using FTDI module, and a Uno with the chip removed...
Is DTR connected or is that a mistake in the circuit diagram?
Not sure what you mean. DTR goes to the FTDI header through the pin socket (FTDI Basic)
I have no idea if the chips come with a bootloader pre-installed....
Might remake the boards with SPI broken out so I can remedy that.
Sorry, so used to DIP variant I skipped over where DTR was.
They don't install the Arduino bootloader for you....It's just a blank chip from factory IIRC.
Looks alright unless you want to install the diode parallel to the 10K resistor....It may help with dodgy reset circuitry, but it can be added externally.
EDIT: like this.
1N4004/1N4007 alright? (M4/M7)
Should be....That's what I use anyway.
I think you should double check the clock crystal circuit. If using a resonator, the ground may be improperly connected. If using a crystal, it needs two small value capacitors to make it work properly.
I'm using a resonator, and yes it's correct. The schematic looks wrong, but its actually not.
you must understand difference between ISP programig and UART. on your schematic FTDI UART adapter connected to SPI pins.
UPD. wait, in first post it looks better
Haha yes I'm aware. I will NOT be trying to use FTDI to program with SPI. It'll be an Arduino as ISP. Also not sure what the point of those two screenshots are....
I have designed two other ATMEGA328p microcontrollers with a resonator like this:
Both work flawlessly. The schematic is incorrect, however the board files match the pinout of the actual resonator so I don't really care.
without capacitors?
He is using a resonator and it does not require external capacitors.