I am trying to program an atmega with arduino sketch using ISP only (mac user). So I know how to burn a boot loader, and then to program the chip using the TX, RX. But I would like to program it directly using ISP, without a boot loader. So I am using the UNO as a ISP programmer, and trying without success to program a chip on a PCB:
- I upload to the UNO the ArduinoISP sketch
- Connect the lines to the target board (target board have atmega328, crystal, capacitors, LED)
- Choose the board "Arduino pro or pro mini" in the Arduino IDE.
- Choose the programmer- "Arduino as ISP"
- At the beginning I tried to upload a boot loader, to see if its going well, it DID boot loaded the chip,so I know the connections are good, and I am set to go.
Now, I am trying to just upload a sketch using the SAME ISP connection, I didn't touch anything(!) , so I opened the blinking example, hit the upload button, and it's just not working (not in sync).
Again, the goal is now to program a chip with ISP directly, without a boot loader. The reason I boot loaded it is to see it's all connected well.
I can't imagine how the exact same configuration can bootload the chip,and later can't upload a sketch directly using the ISP.
What am I missing here? Can't you use the Arduino IDE to upload a sketch directly as an ISP programmer?