July 8, 2012 AT 11:13 am

First Vial Greater Than Last Vial — Read-Only Archaeology

I’m really enjoying these articles by phooky (Adam Mayer) at NYC Resistor about pulling data from old EPROMs. Aside from the technical information, there’s a cultural aspect too — it gets you thinking about the need for context and the things you commit to digital posterity. He writes:

CHANGING TO ISOCRATIC MODE OF
OPERATION ABORTS GRADIENT AND LEAVES
EVENTS IN THEIR CURRENT STATE

There are incoherent, mumbling ghosts everywhere. A lot of the time they look like this.

These are 80′s-era erasable programmable read-only memories, or EPROMs. They were an immensely popular way to store firmware for embedded systems when the production run size or schedule didn’t make it economical to use less expensive masked ROMs. Then cheap EEPROM hit the market, and EPROMs all but disappeared from devices within half a decade.

TABLE LINE TABLE SAVE HELP
First vial greater than last vial.
End of table.
Table is full.

This is the firmware for an obsolete solvent control system running on a Motorolla 68000 microprocessor, obscurity on obscurity on obscurity. Who’s ever going to need it anyway? Why save the bits?

Gradient and event tables
to be executed simultaneously.
# GIVE ME SOME HELP
Number Out of Range

For the same reasons we record any history: because someday it may prove to be useful, and because someday it may prove to be beautiful.

The above is from the first article he wrote on the topic back in June. He’s since written a nice follow up detailing the process of data extraction. Take some time and check them both out, and perhaps even give it a try yourself.

It makes me wish there was a twitter feed or tumblr for out-of-context ROM dump messages. @Horse_EPROMS?

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2 Comments

  1. I lived that era – if anyone wants a gander at some 6809 or 68000 code for Caltech EE projects, I still have the ROMs, some in the equipment, a couple extra in a drawer that might need a read.

  2. Ah…happy times spent putting these babies under a UV lamp (20 mins to erase) and then writing another version of the code on the device _again_…

    I remember that Motorola made the technically superior 68000, but Intel had a more complete set of compatible devices for their micros. There was a brief tussle, but Intel won.

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