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[on:]

Hello,

I need to program a bare Atmega2560 chip that'll be on a custom made PCB. I would like to use an Arduino UNO or Arduino Mega2560 to act as the ISP. I've looked at the link provided by Arduino on how to burn the bootloader to the bare chip by connecting the 6 pins: MISO,MOSI, SS, SCK, 5 V, and GND. http://arduino.cc/en/Tutorial/ArduinoToBreadboard

After this, you remove the MCU from the Arduino and wire RX and TX to some pins to the Atmega 2560.
What I am confused about is what pins do I need to map to from the Arduino to my Atmega 2560 in order to upload sketches using the Arduino IDE. Also what capacitors and resistors would be needed as well.

Thank you.

[Reply #1 on:]

Attached is a minimal 2560 schematic. 

Look at the datasheet to find the pinout.

[Reply #2 on:]

In a nutshell, I don't understand the process in uploading a sketch after uploading the bootloader on a Atmel chip residing on a custom PCB. I am trying to make sure I have the proper pins on my PCB schematic so I can access them for uploading sketches.

I've looked at the minimal schematic but it hasn't been much help. I guess what I'm wondering is do I just need the same set up as in the image attached, where I am just mapping to pins RX0 and TX0 on the Atmega 2560, AVCC, VCC, and GND in order to upload a sketch to my bootloaded MCU.

[Reply #3 on:]

I've looked at it but it hasn't been much help. I guess what I'm wondering is do I just need the same set up as in the image attached, where I am just mapping to pins RX0 and TX0 on the Atmega 2560, AVCC, VCC, and GND in order to upload a sketch to my bootloaded MCU.

And Reset... Yes