RX02 Repair {Follow Up}

From: steve.lubbers_at_barco.com <(steve.lubbers_at_barco.com)>
Date: Wed Aug 4 07:29:52 1999

Thanks All for the suggestions I've received so far.

To answer a few of the additional questions that cropped up:

I've had the drive for about 11 years. About 5 years ago it worked
correctly, so I'm assuming that internal switch settings are correct (though
I don't have a reference to verify them), and the controller/drive match.

I have a huge collection of disks, some marked RX01, some RX02, none will
boot. I am currently working with an RX02 disk that was used to boot
another PDP-11, then sent to me.

I checked that both drive belts are in place, and used a scope on the photo
transistor that detects the hole. The drive RPM was correct.

tony- This would help
>>>There are some things you can try. Firstly (if you have the programming
>>>info - if not I'll find it), you can try transfering 256 bytes from the
>>>PDP11 to the sector buffer and then transfering it back again (without
>>>going via the disk). This will test most of the controller logic and the
>>>sector buffer RAM. My guess is that this will fail.


>>> -----Original Message-----
>>> From: steve.lubbers_at_barco.com [mailto:steve.lubbers_at_barco.com]
>>> Sent: Tuesday, August 03, 1999 8:51 AM
>>> To: Discussion re-collecting of classic computers
>>> Subject: RX02 Repair
>>>
>>>
>>> I've been trying to bring my old RX02 drive back to life,
>>> with little
>>> success.
>>>
>>> I just received a good bootable floppy, and get the same
>>> results as with all
>>> my old disks, so now I'm looking for hardware problems.
>>>
>>> On a PDP-11/03, With RXV21 controller, and an RX02 drive, the RX02
>>> initializes, attempts to read the boot block, and crashes
>>> to ODT at 000600.
>>>
>>>
>>> > In examining what my system reads as it attempts to boot,
>>> it looks like I
>>> > read every other 128 byte chunk correctly. I haven't
>>> figured out a
>>> pattern
>>> > to the corrupt sections.
>>>
>>>
>>> Does anyone have any RX02 diagnostics, or hardware trouble
>>> shooting tips?
>>>
>>>
>>> Steve
>>>
>>>
Received on Wed Aug 04 1999 - 07:29:52 BST