The hardware.

What hardware do you need to add? You will need an Ethernet port. This consists of:

  • An RJ45 network connector (to connect to your Ethernet cable).
  • A network transformer.
  • An Ethernet chip.
  • Some monitoring LED's.

Usefully, the RJ45, the transformer and the LED's can all be bought as a single unit.
The Ethernet chip can be implemented in a number of ways:

  • There are complete chips that can be bought from companies like SMSC. Many chips are designed for the PCI bus on a PC, but these are not ideal for inclusion in small embedded systems. They also do chips with a more traditional parallel interfaces such as the LAN9215 which will interface to any microprocessor.
  • Some microprocessors already have an Ethernet interface built-in. These will usually require the addition of PHY chip to complete the interface.
  • It is also possible to find Ethernet chips with a serial SPI interface (Microchip ENC28J60). These would be adequate for low data rate applications.

This hardware is not complicated and can easily be added to almost any existing or future design.

This is a picture of a network controlled stepper motor driver (one of 27 in a distributed control system.) The parts needed for the network interface are highlighted.