RX02 Difficulties

allison allisonportable at gmail.com
Sat Dec 16 16:51:48 CST 2017

If you have a system that can create/format SSSD (base RX01 media
format) RT11 can
reformat that as RX02.  Of the top of my hear the command is INIT and
you specify the
drive and /double.  It cannot format a blank disk but it can set a RX01
format to
double density.

Note a RX02 on a PDP-11 will not boot RT11 if it has the RX01 boot drive
in place, you must have
the RX02 driver built into the boot.

Whenever you have a disk fail its advisable to check the heads for crud
buildup (on RX01, RX02,
or RX33 and RX23) as sometimes the binder on the media goes to goo and
coats the head.  If
that happens the next good disk can have the media gouged off.  Been
there done that.  I
always test new media (dir /bad) on drive 2 so if it fails the system
still boots and likeliness
of munging the boot media is lower.

I use my S100 CP/M crate for format blanks for RX01 and using R11CPM I
can copy files
between the two system (sneakerware).

To read a RX02 formatted disk you must have a RX02 or one of the
functional equivalents like a DSD
or Emulex.  PCs cannot without a special board.

A slick trick for Qbus 11s is install a RQDX2/3 and put a RX33 or RX23
drive on that as the formats
they use are PC readable at the base ODS.  I managed to get a few RQDX3s
just for that in the various
Qbus 11s I have.  Even if you do not have a MFM hard disk for the
RQDX2/3 is a good choice for floppies
and it can format media.  It also can store more on the media.


On 12/16/2017 04:21 PM, Jerry Weiss via cctalk wrote:
>  Glad to hear that you cleared that up.   
> For the other floppies.
> 1)  DUMP/TERM/RAD50/END:0 DY1: 
>      If you share the listing that will give us some hints as to the OS on the floppies.
> 2) DIR/BAD DY1:
>     will do a bad block scan to see if can read all of the blocks on the media.  It
>     does not require an RT11 directory, despite the command name.  It uses
>     the utility DUP.SAV with the K option, not DIR.SAV  You will hear the floppy
>     reset if it sees a bad spot as it attempts a retry.  The number of retries
>     is configurable via a SET command.
>     For files with an RT11 Directory, DIR/BAD/FILES will include the file name
>     of files affected by unreadable blocks.
> You can do the same with the RL02 Drives.
> Jerry
>> On Dec 16, 2017, at 2:28 PM, Aaron Jackson via cctalk <cctalk at classiccmp.org> wrote:
>> I just checked all of them in RT-11, out of 12 floppies, two of them
>> were bad, or at least I am unable to perform dir in RT-11.
>> My source of confusion comes from both A) not being able to boot from
>> any of them, and B) not being able to dump them using vtserver. The ones
>> labelled RT-11 don't actually have RT-11 on them, just some random
>> files, and these were the ones I had tried to boot from.
>> I'm not sure why vtserver doesn't seem to work though. I have Kermit in
>> RT-11, is there a way to dump the other drive over this? I would like to
>> put LSI Unix on one of the floppies, can this be done with Kermit too?
>> While on the topic of vtserver, it also doesn't seem to like my RL02
>> drive. If I try to write to it or dump a cartridge, it tells me that it
>> was unable to read the labelsector. About the thing vtserver has done is
>> launch itself over odt.
>> RT-11 is unable to list the files on the RL02 drive, but maybe they are
>> UNIX or maybe they are dead packs...
>> Thanks,
>> Aaron.
>> systems_glitch via cctalk writes:
>>> We've gotten around the formatting issue by formatting SSSD using ImageDisk
>>> on a regular PC (with a floppy controller that supports single density/FM,
>>> of course). If you want RX02 media there's an XXDP routine to upconvert
>>> RX01s to RX02s.
>>> Thanks,
>>> Jonathan
>>> On Sat, Dec 16, 2017 at 2:02 PM, Chuck Guzis via cctalk <
>>> cctalk at classiccmp.org> wrote:
>>>> On 12/16/2017 10:43 AM, Fred Cisin via cctalk wrote:
>>>>> On Sat, 16 Dec 2017, Aaron Jackson via cctalk wrote:
>>>>>> Well, would you believe it. It was the disks after all. I can't believe
>>>>>> they are all bad!
>>>>> I can believe it.
>>>>> Were they "bad"?
>>>>> Or just not what they were labelled as being?
>>>> I suspect that they weren't formatted to the 3740 spec (26/128 FM).
>>>> ISTR that the RX02 doesn't have formatting abilities.
>>>> The other possibility is that the disks were DS rather than SS
>>>> (different index aperture position).
>>>> --Chuck
>> --
>> Aaron Jackson
>> PhD Student, Computer Vision Laboratory, Uni of Nottingham
>> http://aaronsplace.co.uk

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