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Re: Sparcstation-1 EPROM



On Mon, 9 Jun 2003, Wojciech Moczulski wrote:

> Few days ago a friend of mine brought me Sparcstation-1. But eprom on this
> machine has been erased throgh battery discharge. I've heard that there's
> possibility to install a kind of "typical" eprom chip with uploaded
> suitable code that'll will make this machine alive again. Could you tell me
> where can I get such a code and what type of chip should I use?

The device you're referring to isn't an EPROM - it's an NVRAM. It contains
a 2k x 8 static RAM, along with a real-time clock circuit, and a 3-volt
lithium cell which is designed to keep the whole lot powered up in the
absence of an external power source for up to 5 years. Of course most
machines are running for a significant part of that 5 years, so the
lithium cells last much longer (up to 10 years or longer) in some cases.

The NVRAM replaced the IDPROM used in machines before the Sparc system.
The first 32 bytes of the static RAM hold the 'idprom' information, which
includes the system board's serial number, H/W manufacturing date, it's
MAC address, machine type (not used from the Ultrasparc systems up), and a
checksum. It's read at power-on time.

Mark Henderson maintains the Sun IDPROM/NVRAM FAQ at:

http://www.squirrel.com/sun-nvram-hostid.faq.html

and it's a must-read if you want to do anything with NVRAM's.

The devices themselves are easily replaced and re-programmed. I sell them
through my Sun surplus business here in Australia, and some of the
electronics retailers in the US sell them over the counter.

The device you need is a 48T02 2k x 8 timekeeper RAM made by ST
Microelectronics.

Regards,

Craig.

-- 
  Craig Ian Dewick (craig@lios.apana.org.au). http://lios.apana.org.au/~craig
  APANA Sydney Regional Co-ordinator. Operator of Jedi (an APANA Sydney POP).
 Always striving for a secure long-term future in an insecure short-term world
   Have you exported a crypto system today? Do your bit to undermine the NSA.



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