Ethernet Shield on Arduino Mini I would like to connect my custom-made Arduino with an Ethernet shield but I'm not so sure I can.
The problem
My board is using the design from the Arduino Mini which lacks the ATmega16U2 which does the USB-to-serial conversion and adds the ICSP pins. I think you get the point... I have only the ATmega328P on the board. Nothing else.
Is it even possible to work my way around it without adding the ATmega16U2? I can't find the chip anywhere on Ebay.
You can just connect the pins used on the shield the the corresponding pins on your custom board. Check the Schematic to see what pins are used for what (and which can be left unconnected)

The only thing you need to lookout for is, that the ethernets shield seems to require 3.3v (the shield has it's own 3.3v regulator, so you only need to connect 5v)

That 16u2 doesn't do anything but usb-to-serial. It's not needed for the ethernet shield.

The ISP header is just 5v, GND, and the 3 SPI pins and reset. But those SPI pins are also broken out to the pins 11, 12 and 13.