Sorted by Squirrels.

Sunday, 21 June 2009

Happy Father's Day!

The Atom needs some non-volatile random access storage. I ran out of suitable patience burning EPROMs when updating the firmware for the new MMC board. The old firmware was developed with the aid of an MMC simulation that I shoehorned into the MESS emulator. The simulator allowed me to code against a just-accurate-enough model of an MMC card in SPI mode. The new interface doesn't have such a luxury yet. So I got thinking, and decided that the 32kx8 FRAMs that I got from Ramtron recently would do as an EPROM replacement. But I'd still need the firmware in EPROM available to bootstrap from... Hmm. I'd also been meaning to build a copy of a neat videoram replacement card that I found in an Atom belonging to a friend. So that was that, really. Or rather, this is that:

At the moment it's only the video ram replacement side of the equation. The flying lead takes A10,11,12 from the main board. The rest of the signals are picked up from the vacated 2114 sockets. The empty socket is going to take the FRAM and some decoding logic will live adjacent, unless I can find suitable signals to pick up from the motherboard.

Not all underbellies are soft; This was quite hard, actually:



I shall return with news of FRAM. Dear, dear FRAM.


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About Sir Morris

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Loves: Old computers, Old Techno, Old ladies. Cake.
Hates: New computers.

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