---
title: "W5500io PIC12F519's job"
url: "https://maker.wiznet.io/forum/10341"
markdown_url: "https://maker.wiznet.io/forum/10341/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "Zarck"
created: "2014-07-01T09:35:03+09:00"
last_activity: "2017-05-04T08:33:19+09:00"
language: "en"
views: 566
replies: 4
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5500io PIC12F519's job

## Question

Asked by Zarck on 2014-07-01 in Ethernet Chips.

Hi Everyone,

I was looking at the schematic of the W5500io and I was wondering what was the real purpose of the PIC12F519?

Is it its job to set the MAC Address, default IP address? What else?

In the future, we would like to integrate W5500 to our boards and we are currently thinking about a possible design.
Does this PIC12F519 is essential?

Thanks!

## Replies

### Reply 1 by kevinlee, 2014-07-02

Hi! Zarck,

The PIC12F519 is not essential for W5500 applications.
If you can have your own MAC address and can save it in the EEPROM or Flash Memory, then you don’t need the PIC12F519.

You should purchase the MAC addresses to be used in your system at the IEEE ([www.ieee.org](http://www.ieee.org)).

Thank you,
Kevin

### Reply 2 by Zarck, 2014-07-02

Thank you for your reply and the information!

### Reply 3 by Zarck, 2014-07-03

Hi,

Regarding to the MAC address to buy for our Ethernet design.

I looked at the IEEE website, but for testing purposes I have a question:
Is it possible to buy from Wiznet the W5500 with the PIC12F519 including a MAC address?

Or I was thinking of an alternative, using this Dallas Semiconductor 48-bit Node Address Chip which provides a valid MAC Address. But the question would be How to communicates with the W5500.
[url][Search Results: url%5D - Maxim](http://datasheets.maximintegrated.com/en/ds/DS2502-E48.pdf%5B/url%5D)

Also, what are the step of the communication between the PIC and the W5500?
The PIC is giving the data to the W5500 at the very startup (power switched on) of the board or the W5500 is asking at a particular time?

Thanks,
Marc

### Reply 4 by Zarck, 2014-07-04

Hi,

Thank you for your help !
We chose the option of a EEPROM from Microchip (93AA46AE48).

Thanks,
Marc

---

Source: https://maker.wiznet.io/forum/10341