On Fri, 2 Dec 2011 13:17:46 GMT, lid
(Windmill) put finger to keyboard and composed:

If you disconnect one of the RAM buffer pins, does the LED pattern
change? Doing so should result in a Sector Buffer Error (error code
03h).

Not sure where I would do that. I haven't disassembled the drive and
don't have a full technical manual for it, and I'm not sure where I
would be able to disconnect (and then later reconnect) a single pin on
a tiny SMD.

There is a product manual in several parts he
ftp://ftp.octek.com.hk/UTILITY/UTILI...GFOOT/BG_CY_AT

There is a block diagram of the electronics in section 5.2 of chapter
5.

The DRAM is a 64K x 16 IC. You should be able to locate its datasheet.
I suggest you lift one of the data pins.

I have a database of datasheets he
http://www.users.on.net/~fzabkar/HDD/HDD_RAM.html

Should the flash pattern be interpreted as hex code 8A ? Do you have
something which lists these codes, or a link to something which does? I
found some information by Googling, but nothing about error codes from
the LED.

FWIW, there are error codes listed for the ATA Execute Drive
Diagnostic command (section 6.7.7 of the manual). I don't know if they
bear any resemblance to your codes, but 8Xh indicates error number 0Xh
for drive #1 (slave).

If putting a fault on the DRAM results in a flash code of 83h, then
this would be consistent with the table of errors in the manual.

- Franc Zabkar
--
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