~e; correction: hard drives
From
brian carroll <human@electronetwork.org>
Date
Sat, 1 Jan 2005 23:41:42 -0600
Cc
johannes_richter@gmx.net
I am grateful to Johannes Richter for finding a
major error (and the subsequent inaccuracies) in
the essay 'deconstructing hard drives', and it is
especially appreciated as my work is self-taught
explorations and the error was catastrophic in
this case and so I wanted to describe the error.
The chip that was in the harddrive that runs the
circuit to move the actuator arm had markings
which were misread, in short I added a '1' to
the number and got the wrong datasheet, wrong
schematic, and speculated from this point on.
The most basic investigation would show that
the pin number was 24 not 28 and that it did
not look like the logo of the semiconductor
company Cirrus, rather it is more like Cherry
Semi (now either Ontario Semiconductor or Intel,
from efforts to locate the company's datasheets).
Here's an interesting site found as a result of
the search for additional chip information:
'semiconductor logos'
http://www.dialelec.com/semiconductorlogos.html
The attempts to find datasheets for the existing
chip have been dead-ends, with no information
available except the part number for bulk-level
purchases/bids for what seem to be chip brokers
in China. Otherwise no information exists on
what the chip is/does, at least that I can find.
So my apologies for the major error, the new page
has been updated with an acknowledgment of this
error and the schematic and pinout configuration
graphics for the wrong chip removed from the site.
I will try to be more careful in the future, as I
am learning and did not comprehend the company
logos on the chip, but in hindsight remember it
was a curiosity why the logo was what it was.
A new scan of the chip is online, luckily it
was saved as an artifact so it could at least
be corrected. Next time the harddrive information
itself would be the most valuable to aid in any
general investigation, such as the size of the
harddrive, company which made it, as maybe a
chip's data or functioning could be deduced
from industry literature or some other way.
In any case, thanks to Johannes and I hope to
dismantle a new hard drive again to look into
chip/circuit functioning further, as there is
so much to learn and it's all the more curious.
I'll work harder to present accurate information.
Brian
– deconstructing the computer hard drive –
http://electronetwork.org/education/decons/harddrives.htm
the electronetwork-list: electromagnetism and culture...
archives: http://archives.openflows.org/electronetwork-l/
un/subscribe: http://www.electronetwork.org/list/