Maxtor LXT-200A firmware issues

[philpem]

I've got a pair of Maxtor LXT-200A drives on the bench. Does anyone have any info on these seriously old drives, or the similar MXT series?

One is a working drive with nothing of any value on it and identifies itself as "Maxtor LXT-200A 1.02BHAT".
The other (which I'd like to try and recover for educational value) spins up and clicks a bit, then identifies itself with firmware version "1.02BROM".

Going by previous experience with Maxtors, that means it wasn't able to load the firmware from the platters and has dropped into the boot ROM to wait for a firmware download.
Reading and writing sectors doesn't work on the "BROM" drive.

I've hooked a scope up to the RS232 port - the transmit pin floats high, but the receive pin stays low.
CNMI (nonmaskable interrupt) floats high, shorting it to ground doesn't seem to change the drive's behaviour.
I'm waiting for a 2mm pitch connector to arrive to do some more detailed tests.

Thanks.

Code:

J4  Service Connector Pin Assignment
------------------------------------
     ----+------+------+------+------+------+---PCB
         |Pin 2 |Pin 4 |Pin 6 |Pin 8 |Pin 10|
         |CNMI  |DTR   |GND   |SPDL  |-LED  |
         |      |      |      |Pu.REF|DRV   |
         +------+------+------+------+------+
         |Pin 1 |Pin 3 |Pin 5 |Pin 7 |Pin 9 |
         |GND   |DTX   |GND   |N/C   |+ 5V  |
         |      |      |      |      |      |
         +------+------+------+------+------+
When an LED is connected to pins nine and ten, it functions in the
same manner as the LED which is mounted on the disk drive's face-
plate. This is typically used in cases when the drive is mounted in a
position where the LED is not visible or the faceplate is removed.

Pins three (transmit data, DTX) and four (receive data, DTR) are the
main communication lines. Pin two is for factory use only. Pins five
and six are signal ground lines. Pin eigth is used to synchronize the
spindles in multiple drive applications.