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Scored an RX02 !

Lou - N2MIY said:
The bits in your earlier picture look like they're from the spindle that engages the hole in the disk. I hope they're not from one of the currently installed spindles!

The jumpers for RXV11 are described in the qbus interface handbook starting on page 461. http://bitsavers.informatik.uni-stuttgart.de/pdf/dec/qbus/EB-23144-18_QbusIntrfs_1983.pdf

Yes, these drives are DX0: and DX1: .
Click to expand...

Hi Lou,

Thank you very much for your assistance. Yes, I have that document. I was so intent on looking for M7946 that I forgot to also look for RXV11 (Why do they have two names for everything, anyway?). DOH! Anyway, that is exactly what I needed to confirm that my board is indeed wired for the factory default.

Hmmmm. Yes, I guess I will have to disassemble my RX01 to confirm whether or not those bits came from one of the drives. I was hoping not to have to do that, but I cannot see inside the drives well enough to get a look at the upper portion that comes down to engage the diskette.

Oh, well, I guess that's all part of the hobby!

Thanks again for your attention and support.

smp
 
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Lou - N2MIY said:
The bits in your earlier picture look like they're from the spindle that engages the hole in the disk. I hope they're not from one of the currently installed spindles!
Click to expand...

I have now disassembled the entire assembly in order to get a good look inside the drives. Yes, the "ears" around one of the drive spindle diskette holders are all broken off. The other drive seems to be OK.

Prior to disassembling it all, I did try it out with my new M7946. I booted up as normal from my SCSI drive into RT-11. I heard some initialization clacking from both drives - probably the heads being pulled back to track 0, or something like that.

I put in a random old 8 inch floppy disk into both drives, and attempted an INIT DX0:. After answering Y to the "Are you sure?" prompt, I thought that I heard the head load on one of the drives, but I couldn't tell which one. Then the whole system simply went to sleep on me. I expected some sort of time-out and have RT-11 come back with some sort of error message, but after a couple of minutes that didn't happen, so I issued a couple of control-c's to get the system's attention again.

During that time I waited, I could not tell if the disks were spinning or not (the motors are turning and the belts are OK - turning the motors manually did turn the spindles), and I did not hear the head mechanism stepping along, either, so I don't know if anything was happening at all.

Now I am wondering - do I need any special DEC formatted floppy disks? Is there some formatting that the system will be looking for in order to carry out the INIT command?

If so, does anyone know where I might be able to pick up some good used or new-old-stock DEC floppy disks?

Final question (for now): Which of the drives is DX0: and which is DX1: ? with no indicator LED on these drives, and all the noise going on when they are running, I have not yet been able to tell which is which. Also, I'd like to make sure that my "good" drive is in the DX0: position when I reassemble this beast.

Thanks for listening!

smp
 
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Hi, RX01 and RX02 diskes come with low level, track and sector , pre formated, the drive itself cant do this format, so yes need to get some genuine RX disks, they come up every now and again, Iv recently got 2 boxes of 10, one from the UK and one from the USA.

Now, I understand that his low level format is in fact a standard singe density one and that it is [possible to hook up and early PC to a standard 8 " drive and format a "normal" 8" disk and you can then use this in a RX01, I have 2 boxes of Dysan disks I intend to try this with sometime but not had the time yet.
Pitty about the disk holder, I wonder if you could get one 3D printed ?, Im considering this for some front panel switches for one of my 8's.
DaveH
 
smp said:
OK, I now have a few DEC 8 inch floppy disks on the way to me:

http://www.ebay.com/itm/370965870739?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Hopefully, these will do the trick?

smp
Click to expand...

If not, someone here should be able to format up some RX-01 or RX-02 disks for you. I have an SMS-1000 and it has built in support for formatting RX-01, RX-02, RX-03 (double sided) disks. I haven't actually tried exchanging disks formatted there with my real RX-02 drive, but I assume that should work fine. I think I have a few unused 8-inch disks on hand around somewhere.

-Glen
 
If you should ever see a DSD-880 with a dead internal hard drive for cheap - grab it. It can be used stand-alone to format RX02 disks.
 
If the ones you bought don't do the trick, let me know. I have a PC fitted with 8" drive and can format RX01 disks.

More disk tricks: 1.) Punch new sector holes in the single sided location to use double sided 8" disks as RX media. 2.) Punch two sets of holes to actually use both sides of the media (flippy disks).

Lou
 
Lou - N2MIY said:
If the ones you bought don't do the trick, let me know. I have a PC fitted with 8" drive and can format RX01 disks.

More disk tricks: 1.) Punch new sector holes in the single sided location to use double sided 8" disks as RX media. 2.) Punch two sets of holes to actually use both sides of the media (flippy disks).

Lou
Click to expand...

Hi Lou,

Thanks very much for the offer, and also the tips!

I'll let you all know how things go.

smp
 
OK! I had a couple of adventures trying to obtain some original DEC 8 inch floppy disks, but suffice it to say that I have some disks now and I have been trying to check out my system.

As a refresher, I have a PDP-11/23, and I have an Emulex SCSI controller that I normally boot from to get into RT-11, and I have an M7946 RXV11 interface to use with the RX01.

Today, I put in one of the official Digital 8 inch floppy disks, and attempted an INIT DX0:. After answering Y to the "Are you sure?" prompt, I heard the head load. Then the whole system simply went to sleep on me. I expected some sort of time-out and have RT-11 come back with some sort of error message, but after a couple of minutes that didn't happen, so I issued a couple of control-c's to get the system's attention again. I tried a few of the disks, just to make sure, but it was the same every time.

I figured that I would try to use XXDP to see what is going on. To make a long story short, I find that ZRXAF0 - RX11/RX01 System Reliability and ZRXBF0 - RX11 Interface Test seem to be the most promising ( especially as they are the only XXDP diagnostics for RX01 that I found ) but I note that they say they are for RX11 and I have RXV11. I am hoping that the only difference is RX11 is UNIBUS and RXV11 is QBUS, but I don't know.

I booted the TU-58 tape image 11xx_4.dsk provided by the AK6DN web site, using the TU-58 emulator.

I issued the command: R ZRXAF0.BIC

and I see this:

Code: 
MAINDEC-11-CZRXA-F

SWR = 000000 NEW =      <- I typed a CR here
RXCS = 177170 RXDB = 177172 INT VECTOR = 264

and the terminal cursor stayed right after the VECTOR = 264.

After a few minutes, it typed:

Code: 
TEST HUNG

007200
@

dropping me back into ODT.

I saw in the PDP-11 Diagnostic Handbook that I could ask it to restart at location 204 to get a dump of all errors, so I did:

Code: 
@204G

RX11 DUMP
MAINDEC-11-CZRXA-F

DRIVE(S) P=0 T=0 S=0
NO DRIVES READY

002536
@

dumping me back into ODT again.

I have a few questions at this point:

Can I use these XXDP diagnostics for my RXV11 and RX01 combination, even though the diagnostics indicate they are for RX11 and RX01?

I looked around on Bitsavers and I have obtained the RX01 User's Manual, RX01 Maintenance Manual, and RX01 Schematics. I see that all of this documentation refers to the PDP-8 interface card or the PDP-11 interface as being the UNIBUS quad wide M7846 ( and I have the QBUS double wide M7946 ).

Does anyone have any suggestions for running there diagnostics? And, if these actually are OK for me to use with my system configuration, how do I break out of a diagnostic and get back to the XXDP OS without having to type in the TU-58 boot code all over again? I have not found any user-friendly documents on how to actually use these diagnostics.

As well, what are your suggestions on proceeding with my troubleshooting?

Finally, my disks that I obtained are marked as RX2 on the DEC labels - I assume this means they are originally for RX02. I know that RX02 was double density and my RX01 is single density. Can this be fouling me up at this point? I remember reading that double density is recorded at higher flux density (or some such like that), so I am wondering if there is any difference in the timing signals that may also be giving me trouble.

Thanks for listening, and thanks for whatever you may have to offer me.

smp
 
Oh, we have advice. It's just that I've been having my own butt kicked lately by my second DSD440 (problem in the read/write controller, 2911 based. Deja vu all over again...)

It seems possible that your RX02 floppies are not making the RX01 happy, but it may be more than that. I have seen the utilities for making RX01 floppies into RX02 floppies on an RX02 drive, but I can't remember any routines for making RX02 floppies into RX01 floppies on a RX01 drive. If the drive still will not come ready with known good RX01 media, I'm not sure how much more use any computer based diagnostics are going to be. Then, I would start diving into the RX01 manuals and print set.

I take it you have no other means to format RX01 floppies, like no PC with 8" drive? If worst came to worst one of us can reformat your floppies for you.

Lou
 
I may be wasting your time but in my limited little world I have thought that RX-01 and RX-02 media is different and not compatible. I have RX-01 disk and know they will not work in the 02 drive unless I change the switches inside the drive to be compatible. And just the little bit that I have played with the 01 drive know it don’t like the 02 media, but when it comes to this stuff remember that I may not be the sharpest tool in the shed.
I have a RX-01 with disks that I plan on setting up with the 11/10 when it gets here but playing around with the RX-01 have to say that there aint much the same between the 01 and 02 drives. On one of my YouTube videos for the 11/23 I show formatting and file copying on a RX-02 (look under rafantini8) but consider myself to be far from an expert on the drives.
 
Qbus said:
I may be wasting your time but in my limited little world I have thought that RX-01 and RX-02 media is different and not compatible.
Click to expand...

Correct. RX01 is IBM 3740 128 byte sector single density.
RX02 media will not work on an RX01
 
The way I understand things from the manuals is that an RX02 drive should be compatible with both RX01 an RX02 formatted media, and an RX02 drive should be able to change the format of RX01 formatted media into RX02 formatted media, and the other way around too. (Although if the media is neither RX01 nor RX02 formatted, it needs to be formatted as such somewhere else first).

From the RT-11 System User's Guide, AA-5279C-TC, March 1983
AA-5279C-TC_RT-11_System_User's_Guide_Mar83.pdf

The FORMAT command formats disk and diskettes, and verifies any disk, diskette, or DECtape II except MSCP devices.

Formatting is advisable under the following circumstances:
When you wish to format an RX02 double density diskette to single density, and vice versa.

NOTE
You can format a diskette (RX01 or RX02) only when you have mounted the diskette in a double-density diskette drive unit (RX02). Unless you use the /SINGLEDENSITY option, the system will format diskettes in double-density format. If you attempt to format a diskette in a single-density drive unit (RX01), the system will print an error message.

/SINGLEDENSITY Use this option to format an RX02 double-density disketee in single-density format. The following example uses the /SINGLEDENSITY option to format a diskette in RX02 drive unit 1 as a signle-density diskette.
.FORMAT/SINGLEDENSITY DY1:
DY1:/FORMAT-Are you sure? Y
?FORMAT-I-Formatting complete
 
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Al Kossow said:
Correct. RX01 is IBM 3740 128 byte sector single density.
RX02 media will not work on an RX01
Click to expand...

Please forgive me if this is a dumb question: Are you stating that an RX01 cannot read/write disks that were formatted/written in an RX02, or that the required media is physically different? I don't understand yet whether the RX01 and/or RX02 requires pre-formatted media like a TU58 does, or if blank/bulk-erased floppies can be formatted on an ordinary RX01/RX02 drive. I've just gotten my first PDP-11+RX02 system up and running over the weekend, so I still have plenty to learn.
 
Lou, Qbus, Al, Glen, thanks a million for your responses.

This is a disappointment, but I am not surprised.

So, to be perfectly clear. Despite the title of this thread, I actually acquired an RX01 even though it was advertised as RX02. I believe it to be working, I just have not been able to acquire any RX01 compatible floppy disks. Floppy disks cannot be formatted by my system as they are in an S-100 system or a CP/M system. I have a very nice set of floppy disks marked as 'RX2' which probably means that they are for an RX02 system.

Does anyone out there have a couple of official RX01 floppy disks they can part with, or can anyone create a couple of known good RX01 floppy disks?

In the meantime, I will continue scanning eBay for any offerings that might come up.

Thanks again for your replies and assistance.

smp
 
Hi All;
SMP, I am mixed up, not all that unusual.. If the RX01's are Single Density and they are IBM compatible, then You should be able to format then in Your S-100 system.. Which Boards and which processor do You have ??
If it is a Z-80, I had a format program that was able to do all sorts of formats, not only Single but Double Density and there was not a problem switching between the two.. Its mainly setting up the parameters..
THANK YOU Marty
 
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