mac addresses

Den fredag den 26. september 2014 02.49.17 UTC+2 skrev John Larkin:

how many do you need?

if only a few I'd just buy a bunch of the cheapest NICs I could find

-Lasse

how many do you need?

--
Chisolm 
Republic of Texas

You can get a small block for a few hundred,

Or just get a Microchip EEPROM with a MAC address already burned into it.

Cheers

500, 1K maybe.

John

--

John Larkin         Highland Technology, Inc 

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

PM me at the earthlink address in the header. I have a block you can use.

--
Chisolm 
Republic of Texas

...hold the lettuce and mayo; will duck the golden arches.

Don't know if you're allowed to purchase MAC ad anywhere from IEEE. Atmel (may be Micrchp) are chipping small SO-8 E2P with factory read-only 48bits EUI (24bits Atmel + 24bits Unique extension) If platform HW/SW allows, it become easy to read and set MAC for eth0 interface with u-boot with setenv ethaddr XX:XX:XX:XX:XX:XX

That's what i did in my last project.

Best regards, Habib.

Hi John

You can buy them here:

MAC Address Chips. Need fast, easy, inexpensive access to MAC addresses? Buy Microchip?s MAC Address chips today!:

Quote: "... The EUI-48 node addresses are sourced by the IEEE. They offer two options based on volumes. ... Microchip?s new MAC address chips, specifically targets the issues listed above providing customers with fast, easy, inexpensive access to plug-and-play EUI-48 enabled MAC Address Chips. Every one of these devices will be uniquely programmed with a different EUI-48 address and will also come write-protected to ensure tamper-proof codes. These chips have an additional 1.5Kb of Serial EEPROM functionality that is a useful scratch-pad area to buffer small amount of data or to store configuration settings etc. Finally, they are designed to work in the popular I2C, SPI and UNI/O busses. ..."

Glenn

We've used SPI MAC address chips. But we're doing a new product where it would be more convenient to put the mac address, and the IP address, and some other cal and ID stuff, in a file on a flash chip. This will be another MicroZed project, running Linux.

We could print up a roll of mac address labels, put that in stock, and just peel the next one off and stick it on the box, and add that to the cal file with the other stuff.

Joe has kindly donated a section of a MAC address block that he owns, so we'll use that.

--

John Larkin         Highland Technology, Inc 

jlarkin att highlandtechnology dott com 
http://www.highlandtechnology.com

As long as the MAC address can not be easily changed or erased. Otherwise it eventually becomes a problem for the user.

In the 1990's SUN put their serial number in a battery backed-up RAM chip. Eventually the battery died and the world had a huge pile of dead SUN computers with a serial number and MAC address of 82FFFFFF.

There was a software fix, and eventually a lot of us replaced the battery on the chip (it was glued on and then potted), but the original number was long lost. Someone sugested to use 0xcoffee as the serial number, (the hardware put 82 on the begining) and I had a string of SUN workstations on a LAN with MAC addresses 82c0ffee, 82c0ffef, 82c0ffed, and so on.

It worked, but played hell with serial number based software. :-)

Geoff.

--
Geoffrey S. Mendelson,  N3OWJ/4X1GM/KBUH7245/KBUW5379