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Lou - N2MIY
August 18th, 2010, 06:09 PM
For anyone interested, I've uploaded a few pics of a recent project that has been going well so far. I've been putting a pdp 11/04 back together from parts. I do not have the front panel, so built my own. The machine is working with 32kW of core running RT11 off of RX01 floppy. The next steps involve making it pretty, putting it in a rack, then populating the unibus with various fun options I have accumulated. This is a good point to start looking through the album:

http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4322

Special thanks are in order to Tim for providing many of the parts.

This is about 80 hours of work after cleaning, assembling, building, troubleshooting, etc. This is my very first unibus machine and I have been learning a lot.

Lou

pontus
August 18th, 2010, 11:57 PM
Wow! Good work. Having worked with an 11/70 PSU I know the regulators can be a pain. If it was an OEM machine, It might not have had an operators console.

Is the operators console any different from an 11/23 console?

Also, is that a VAX I see in the background?

Lou - N2MIY
August 19th, 2010, 03:35 PM
Pontus,

Since you bring up working on the regulators, I will elaborate on two especially painful parts. First, the transformer is in a separate part of the chassis and the harnesses to the regulators are pretty short. This makes moving a regulator out of the chassis to a convenient to work on location while having it energized pretty difficult - in a fully assembled machine. Fortunately, this machine had been torn down so far that the power distribution PCB had been removed from the main chassis. Only the bits necessary were on the bench as I worked on the regulators.

Second, there is a power diode in a TO5 case that I cannot find a cross for. It's used in a few of the regulators, including the H745. It's an NAE model NSR8117. I have not been able to find a datasheet on this diode anywhere. NAE was a small diode manufacturer in Lynn, Mass. that was bought up in the 80's by Diodes Inc. After poor financial performance, the Lynn plant was shut down in 1990. Of course the current Diodes Inc. website knows nothing of this particular diode. If anyone out there has an NAE databook on their shelf and can scan the datasheet for this diode, I would be greatly appreciative!!!

I usually like to fix everything, but I had one left over H745 that I scavenged the good NSR8117 diode out of. I would really like to make this H745 whole again as a good spare.

As for the console, the model list does say that this 11/04-JH was supposed to ship with the KY11-LA. So, it did have one once....

In the background is an empty option rack from an 11/780. I was given that by Tim when he was cleaning out before he moved. It was empty when he got it. It is really strong. It can only fit five 10.5" tall devices (one less than an H960) but it looks strong enough to hold five RA80s! I plan to move the 8/e, RX02, two RK05s and the TU60 into that rack (eventually....) Rearranging the equipment in the racks is not as fun as troubleshooting...

Lou

pontus
August 20th, 2010, 04:32 AM
Pontus,
In the background is an empty option rack from an 11/780. I was given that by Tim when he was cleaning out before he moved. It was empty when he got it. It is really strong. It can only fit five 10.5" tall devices (one less than an H960) but it looks strong enough to hold five RA80s! I plan to move the 8/e, RX02, two RK05s and the TU60 into that rack (eventually....) Rearranging the equipment in the racks is not as fun as troubleshooting...
Lou

Sorry, can't help you with the diodes :(

But I think your equipment will look nice in the VAX-rack!

Agent Orange
August 20th, 2010, 11:13 AM
Lou:

Is this what you're looking for?

http://www.amazon.com/dp/B001ISDQVI/ref=asc_df_B001ISDQVI1202285/?tag=globa0a-20&creative=394997&creativeASIN=B001ISDQVI&linkCode=asn

Chuck(G)
August 20th, 2010, 11:49 AM
Don't think so--that's a 7-segment display. Lou's looking for a TO5 power schottky diode. Lou, can you probe a bit and determine the contents of the case? (i.e. diode direction). Since power schottky is commonplace nowadays, it's quite probable that you can find a substitute.

Lou - N2MIY
August 20th, 2010, 03:23 PM
Chuck,

The case is the cathode, both pins are the anode. I have uploaded the schematic here: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4333

It looks to me like a snubber for the output filter coil. In this application, it would make sense to be a Schottky diode for speed.

I suppose a cathode case TO220 power Schottky diode could work here mechanically also if it had sufficient ratings. Any suggestions?

Lou

Chuck(G)
August 20th, 2010, 03:49 PM
How about an MBR1035? Should be more than adequate for the application. You probably could get by with an axial-lead diode like an MBR3100.

Lou - N2MIY
August 22nd, 2010, 07:02 PM
Chuck,

MBR1035 looks good. It is case cathode TO220, plenty of current and good voltage ratings. Looks like a winner. It will go on my next DigiKey order. Thanks!

Otherwise, we now have an RL11 installed and and RL01 connected. Installed another DL11 for an emulated TU58 (DD: ). Both are also bootable. Still no XXDP yet though. I need to make a small monitor bootable TU58 image.

Lou

AK6DN
August 22nd, 2010, 09:20 PM
Chuck,

MBR1035 looks good. It is case cathode TO220, plenty of current and good voltage ratings. Looks like a winner. It will go on my next DigiKey order. Thanks!

Otherwise, we now have an RL11 installed and and RL01 connected. Installed another DL11 for an emulated TU58 (DD: ). Both are also bootable. Still no XXDP yet though. I need to make a small monitor bootable TU58 image.

Lou

Take a look at: http://www.ak6dn.dyndns.org/PDP-11/TU58/ for bootable TU58 xxdp images with diagnostics. I have created image files with basic CPU diags for 11/34 and 11/44, but not 11/04. I could make an 11/04 basic CPU diags image if there is interest.

Don
AK6DN

Lou - N2MIY
August 23rd, 2010, 02:46 PM
Thanks Don,

I will use the 11/34 image as a starting point. I will swap out the F??????.BI? routines with the G??????.BI? for the 11/04 processor. I have spent plenty of time with Will's TU58 emulator and have built various images over the years. It will be a good time savings for me to start with your 11/34 image though. If I think I have made something respectable, I'll send you a copy to include with the rest of your files.

Lou

AK6DN
August 23rd, 2010, 11:25 PM
I went ahead and generated an 11/04 base CPU plus memory and M9312 diagnostic TU58 image as 1104_1.dsk and posted it (simple for me to do since I have a bunch of perl/shell scripts that extract diagnostic files from the XXDPv25 master RL02 disk image and build a custom TU58 image).

You might also look at the TU58 emulator links on that page. I rewrote (basically from scratch) the original Univ of Rochester TU58 emulator by Dan Ts'o and cleaned up the code. With the timing switches on to make it behave like a real (ie, slow) TU58 it even passes the DEC TU58 diagnostic ZTUUF0.BIN.

Lou - N2MIY
August 29th, 2010, 05:05 PM
Well, we've got RXDP floppies made now from the DDDP. I used Will's TU58.exe emulator. I will have to try the emulator on your site someday, Don. I was hoping that it would work on a DOS PC, but alas it needs Windows. I use Will's on a dos laptop (dec HiNote, of course.)

With the ability to run diagnostics, I connected one of my old RL01s and finally repaired it. The upper head was electrically dead. I had a set of heads and positioner from Tim, so I replaced the upper head only and did a head alignment. My one and only good RL01 pack (also from Tim) works just fine. All errors were reported as soft by the exerciser routine. Here's a fuzzy picture of the setup now: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4370 . Here is a fun closeup of the RL01 with the guts hanging out : http://www.vintage-computer.com/vcforum/album.php?albumid=63&attachmentid=4371 .

This system is coming together. 11/04 with 32kW of core, RX01 floppy (256kB - RX: ), RL01 disk pack (5MB - DL0: ), emulated TU58 (DD: ) running RT11 V5.0. I have the DL: boot rom in my M9312, so no more manual bootstrap entry! Now I need to finish a cosmetic front panel and put it all in a rack. Later I will connect my TU60 from my 8/e for the hell of it (I have TA11 controllers) and a DEUNA (the Kent State small rt-11 tcp/ip package will run on this hardware with this little memory.)

Lou

pontus
August 29th, 2010, 11:29 PM
I have a bunch of RL01 disk packs if you want (free for cost of shipping, I have original boxes). Unfortunately both my RL01 drives seems busted :( So I have no way of testing right now. Also I'm uncertain what is on the packs, so if you could make images of them that would be good.

Lou - N2MIY
August 30th, 2010, 05:05 PM
Pontus,

Thanks for the kind offer, but I'm afraid that the postage would be killer. There should be plenty of packs on this side of the pond still waiting to be rescued.

Anyway, you should fix your RL01 drives. What is wrong with them?

Lou

pontus
September 1st, 2010, 03:05 AM
Pontus,

Thanks for the kind offer, but I'm afraid that the postage would be killer. There should be plenty of packs on this side of the pond still waiting to be rescued.

Anyway, you should fix your RL01 drives. What is wrong with them?

Lou

I should! I haven't investigated further. I have two, both show the same behaviour. When I press the load button the drive spins up but the load light doesn't come back on. One never worked and the other worked up until a week or two ago :(

I did remove the SLU card to get a look at the cable. (I tried removing just the cable but It wouldn't budge). Perhaps I touched something I shouldn't have, but that sounds unlikely.

Lou - N2MIY
September 1st, 2010, 03:38 PM
Pontus,

Well, a lot is working to just get so far as having the load button light come on. Now, after the drive spins up, do the heads attempt to load? They should come out, go just past the outer guard track, and seek track zero. Then, the ready light will come on. This is all easy to watch with the back cover up and the head amplifier board in the service position. This is shown in the picture in the earlier post.

Of course you know that the load light will not come back on until the pack has spun down. Is your ready bulb good? Is your fault bulb good (do you get a fault?)

On my drives with the bad upper head (head zero), they would shoot out, past the outer guard track, past all the data cylinders, past the inner guard track, and slam into the travel stop. Then the fault light would come on. Why, because they never found any track on initial load and just kept on going.

For anyone else out there, I should mention that this drive is extemely educational to work on. Doing a head alignment teaches how stuff really works. The track density is so low (2.5MB per surface on a 14" disk) with your own hand and a screwdriver you can advance the heads and "see" the centers of the tracks on the scope. No human could ever have this level of interaction with a 2TB 3.5" drive.

Lou

pontus
September 2nd, 2010, 12:08 AM
I'm certain that the bulbs are good, since they come on when you first power the drive up. I'm not sure the heads come out, I think I would hear them bump into the travel stop if that was the case.

I'll pop the hood and take a look when time allows.

Lou - N2MIY
September 4th, 2010, 05:23 PM
Today I finally finished my nice home-made KY11-LA panel and fitted it to the front of the chassis. Here is the finished unit: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4413

And here is a closeup of the switch / logo panel : http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4412.

I didn't label it as an 11/04 as such. I might upgrade it to an 11/34 eventually, so I wanted to leave the front panel generic. Now all I need to do is make sheet metal top and bottom covers, since the originals are long gone.

Lou

pontus
September 6th, 2010, 03:02 AM
Wow, looks really nice! Quite authentic.

dave_m
September 6th, 2010, 09:25 AM
Today I finally finished my nice home-made KY11-LA panel and fitted it to the front of the chassis. Here is the finished unit: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4413

Very impressive effort. Congratulations on a fine job so far. I always admire people who are not only 'electrically inclined' but also 'mechanically inclined'.
-Dave

Lou - N2MIY
September 7th, 2010, 03:28 PM
Thanks Dave,

I'm a mechanical engineer by trade, so I have no excuse there. There's actually a lot for a mechanical person to appreciate on vintage big iron. On this 11/04, the cooling airflow path is quite interesting and will not work properly without the lower and upper sheet metal covers.

Another of my next projects is to restore two RK05s and an RK8E. I always get a kick out of seeing the different ways to position disk drive heads. Anyone who has ever seen the head positioner on an RK05 will understand why I would be amused. In a way, it reminds me of the carriage on my 1950's DeWalt radial arm saw. Just with a big voice coil at the end.

Lou

pontus
September 8th, 2010, 10:55 AM
Lou,

I hope you don't think I'm hijacking this thread to much :)

I opened up the faulty RL01 today and watched what happened when I press LOAD. ( I also tested with another disk pack, same thing, but I don't know if that pack is good )

1. The drive spins up.
2. The head moves out a little bit and stays there
3. nothing.

So it looks like it finds the guard track but not track zero? Is this an indication that I need to do a head alignment? which actually sound quite fun :)

I also tried to boot the PDP-11/23, but it halts with an error code which just indicates generic RL-disk problems, so it just confirms that something is not right with the disk.

Cheers

Lou - N2MIY
September 8th, 2010, 03:58 PM
Pontus,

If you have a dual trace scope it will be easy to see where the head is ending up. One channel will trigger the scope on and display the sector index pulse. The other channel goes on the output of the head amplifier. Over the guard tracks, there is only one servo burst. Over data tracks, you'll see two servo bursts, then the sector header data. This is actually what is displayed on my scope in the earlier photo of the RL01 with the guts hanging out. The head is out over data in the photo.

The appropriate test points and what to look for are all detailed nicely in the RL01/RL02 techncial manual volume 2 (EK-RL122-TM-001) Chapter 3.

When the head loads, it should seek track 0. In the manual, you will see what needs to be jumpered to defeat the positioner motor and seek timeout timer. Then, you can manually move the positioner with your hand. Withdrawing the heads radially outward, the very next track should be the outer guard track, which will only have one servo burst. If you're not over track zero, you can count the tracks to figure out where you were. I might do this a few times to see if it's ending up at the same track each time.

If you weren't over track zero though, the seek timeout timer should expire eventually and the fault light come up. I wonder why it doesn't do that.

When you say that the heads come out a little bit, can you roughly measure that? I'm wondering if the heads are ever actually leaving the ramp (that lowers the heads onto the surfaces) and loading onto the disk.

As for head alignment, there are actually two alignments, the radial alignment of the positioner (is it really radial, or is it off to one side or cocked at some angle), then the head alignment (heads with respect to each other). I only needed to perform the latter after replacing the upper head because the former was good. Head skew does not appear to be adjustable and would require head replacement if it was off.

I have a feeling there is something else up and that a head alignment won't help (but I am only a novice at this.)

Lou

pontus
September 8th, 2010, 10:10 PM
Lou

Thanks for the detailed answer :)

I will have to get a better scope I think, I only have a small 20MHz scope my dad bought ages ago.

I estimate that the heads went out about one inch, I'll have to get back in there to make a more accurate measure. I sounds like the heads are landing (I can hear them brush against the disk), I believe they actually are supposed to touch the surface of the drive in these beasts, otherwise that might be my problem.

This problem occurred after I removed and reinserted the SLU, perhaps I have a controller or cable problem. I could try replacing the RLV11 (I have spares), but I'm uncertain if the READY light depends on a working controller (the manual you pointed to indicates that its all in the drive). You do get a fault unless you have a cable attached.

Pontus.

Lou - N2MIY
October 13th, 2010, 04:15 PM
Again from the "because I could" file, I put a DEUNA in this 11/04. http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4670

I extended the unibus to the 4-slot expansion backplane and put the dual hex height card set in there. I then sysgenned RT-11 appropriately and installed the RT-11 telnet / FTP package. I moved a nice big file from an FTP server in the garage (on a PC). With only two nodes on the network, the 11/04 was downloading a file by FTP at 6.2 kbytes / second and writing it out to RL02. http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=4669

I think the only thing crazier would be to get a UDA50 and put that in too, then connect it to the RA72. A computer with 32kW of core and 1GB of disk space.

I think the T-11 on the DEUNA might be more powerful than the 11/04 itself.

Next, we probably add the TA11 controller and connect it to the TU60.

Lou

cosam
October 14th, 2010, 12:44 AM
Hi Lou,

I somehow managed to miss this project but photos like these always bring a smile to my face. All those open cases and wires all over the place - great stuff! Makes me want to get back to tinkering with my 11/35 again...

Do you have any tapes for the TU60? I heard they can rip regular audio cassettes to shreds!

Lou - N2MIY
October 14th, 2010, 03:26 PM
Steve,

It's certainly good fun. Fortunately I have half the garage to "spread out" in. I am impressed by folks that are able to work in very tight spaces.

My TU60 has never shreaded any tapes. However, any old tapes, like real dec TU60K media are no longer readable. The oxide comes right off onto the heads. The tape in a compact cassette is nowhere near as robust as dectape (which is encapsulated on both sides). The old cassette tape has no encapsulation. So, I do use audio cassettes. I wrote something about this in a post to alt.sys.pdp8 when I first restored the TU60. Basically, high quality audio tape with a clear leader and a notch added to the cassette housing, works fine. I think I had the best result with some tape from BASF.

I would be intersted to find anyone else with a working TU60. The heads between the two transports in my TU60 are aligned differently (tapes written in one are not interchangable with the other.) I would like to get a tape from someone who thinks their heads are aligned properly and try it in my transports. Then I will re-align to match.

Lou

tradde
October 14th, 2010, 04:02 PM
I don't believe any hard disk head should ever touch the disk surface. A floppy disk sure. But a hard disk spins much
faster. Back in those days 3600 rpm was common. If the heads touch the disk and there is any type of debrib (fingerprint, hair, etc) you have a major problem. You can often hear the high pitched tinging of particles hitting the heads as I did
on my RK05 after I had cleaned them but still missed minor particles. Clean the heads good also.
Tim R

MikeS
October 14th, 2010, 05:45 PM
@Lou:

Tried to send you a PM but it looks like your inbox is full and needs a good purge...

mike

pontus
October 14th, 2010, 11:12 PM
TU60 is the DECassette right? The computer club has one, but I have no idea about function or if we even have a controller.

Lou - N2MIY
October 15th, 2010, 03:25 AM
Pontus,

Yes, TU60 is the decassette drive. It uses Philips compact cassettes. If it hasn't been used in a long time, all of the rubber tires will be dried out and broken. I had to rebuild my tires.

Last night I found the XXDP diagnostics for the TA11 and most of the listings. We are making progress.

Lou (and my overflowing mailbox is now fixed.)

Lou - N2MIY
October 17th, 2010, 05:35 PM
Well, the TA11 is installed and cabled to the TU60. The four controller checkout and tape motion XXDP maindecs pass. However, the data integrity maindec hangs after an initial rewind as it waits for the ready signal from the drive. It looks like my drive is flakey and there is a problem coming ready after a programmed rewind. Both transports behave the same.

Under RT11 I can initialize and take the directory of a cassette. I can copy files to the cassette, but cannot get copy/verify to work. I also cannot copy files back from cassette. It finds each of the file gaps, but passes right on to the next file until the end of the last file, when it rewinds and then RT11 gives a "channel not open" error. But somehow it can take a directory, which means data can be read off the cassette.

Amusingly, it can take a directory of CAPS-8 / OS/8 cassettes. I also don't understand why, but the XXDP block-by-block tape duplication maindec runs without errors, supposedly even verifying the copy! But alas, something is truly wrong, because when reconnected to the 8/e, OS/8 MCPIP hangs right when trying to access the tape, right after a rewind, just like the XXDP data integrity maindec does.

So, the TU60 will come out of the rack and go on the bench while we scope this out.

tradde
October 18th, 2010, 02:18 PM
You'll figure it out, I have no doubt.

Lou - N2MIY
November 14th, 2010, 06:39 PM
A lot has happened over the last four weeks or so. When I put the TU60 back on the TA8E, it didn't work there either. After a bunch of weeks of troubleshooting (and finally buying some card extenders from Douglas Electronics) the TA8E / TU60 is back to working condition. The IOT decoder 7442 on the TA8E was broken and two 8640s in the TU60 were bad. It turns out that 380 and 8640 have the same pinout, so I used 380s. So tonight, for the first time in a long time, I booted CAPS-8 from the original bootable cassette that I built by hand almost four years ago now.

While waiting for my card extenders to come, I fixed up an MI8E diode bootstrap loader. I have no idea what the original diode configuration was for, but I changed the diodes to the RX01 bootstrap. Now the SW switch on my 8E does something! Of course, the MI8E was broken too, but the problem was a 2N3009 that drives the Pulse LA H line. I actually had the replacement. So, now it's the end of an era - I no longer have to fat finger a bootstrap on the 8/E. I can use the rom bootstrap loader to load the RX01 bootstrap, then run OS/8 and use the boot command there to load whatever strap I want (which at the moment is only the cassette.)

Now I need to clean up a bit, and put the TU60 back on the TA11 11/04 and try that again. At least now I know that the TU60 is good!

Lou

pontus
November 15th, 2010, 03:07 AM
Good work! Sounds like a nice little setup.

How much did the extenders cost you?

tradde
November 16th, 2010, 01:28 PM
A lot has happened over the last four weeks or so. When I put the TU60 back on the TA8E, it didn't work there either. After a bunch of weeks of troubleshooting (and finally buying some card extenders from Douglas Electronics) the TA8E / TU60 is back to working condition. The IOT decoder 7442 on the TA8E was broken and two 8640s in the TU60 were bad. It turns out that 380 and 8640 have the same pinout, so I used 380s. So tonight, for the first time in a long time, I booted CAPS-8 from the original bootable cassette that I built by hand almost four years ago now.

While waiting for my card extenders to come, I fixed up an MI8E diode bootstrap loader. I have no idea what the original diode configuration was for, but I changed the diodes to the RX01 bootstrap. Now the SW switch on my 8E does something! Of course, the MI8E was broken too, but the problem was a 2N3009 that drives the Pulse LA H line. I actually had the replacement. So, now it's the end of an era - I no longer have to fat finger a bootstrap on the 8/E. I can use the rom bootstrap loader to load the RX01 bootstrap, then run OS/8 and use the boot command there to load whatever strap I want (which at the moment is only the cassette.)

Now I need to clean up a bit, and put the TU60 back on the TA11 11/04 and try that again. At least now I know that the TU60 is good!

Lou

Congrats,
It must feel good. How did you manually create the CAPS-8 bootable though? Also it's nice to have a bootstrap board.
Manually toggling in a bootstrap a few times is fun, but not for long.
Tim

Lou - N2MIY
November 17th, 2010, 02:35 AM
Last night I put the TU60 back on the 11/04. I have two TA11 controllers that are "close" to working. One has a stuck high receiver for the MSB data bit, the other "seems" to be working fine. The seemingly good looking one does not run the most complicated maindec, still hanging after the initial rewind. It's stuck in a loop waiting for a flag. The controller with the stuck data bit does the same thing. The time has come to start scoping the TA11 controller now.

The problem is that the TA11 controller print set is nowhere to be found in the internet.

Pontus or Steve or any of you fellows with connections, can you check your computer clubs for the schematics for the M7892 TA11 controller? I would be very appreciative.

Pontus, the dual height extender (without socket connector) was ~$19.50USD each. I had connectors desoldered from junk boards from Tim. They are really handy! Now I have the TA11 raised up out of the 11/04.

Tim, as for the CAPS-8 cassette, I posted on alt.sys.pdp8 on Dec. 12 2006 the long story. If you search google groups for CAPS-8 alt.sys.pdp8, it will come up.

Thanks for your help guys,

Lou

pontus
November 17th, 2010, 05:59 AM
Pontus or Steve or any of you fellows with connections, can you check your computer clubs for the schematics for the M7892 TA11 controller? I would be very appreciative
Well, we have a TU60, so there is a chance there is documentation. But it will take some serious archeology to dig it out! We are very cramped up in our storage, so it might take me a while.

Lou - N2MIY
November 20th, 2010, 02:23 PM
We figured out why the most complicated TA11 maindec would not run. The maindec in question is DZTAEB0. The B0 version is the only one I could find anywhere. It was on an image of an RK05 pack on bitsavers. The listing I have, also from bitsavers, is for revision C0.

I thought there was a problem with interrupts, and I was right. The B0 version is missing a CLR PS (clear the processor status word) early in the code that is present in the C0 version. I only saw that by doing a bunch of examines and comparing the code in the machine with my listing. The missing CLR PS sets the processor priority to 0, allowing it to be interrupted by any interrupt. Without the CLR PS, it was stuck at priority 7, thus ignoring the priority 6 interrupt that the TA11 was setting after finishing the initial rewind back to the clear leader.

I say that without the CLR PS that the processor was stuck at priority 7, but that may be a function of the machine I am using. My 11/04 has no proper programmers console, so I rely on using the console emulator in the M9312. In this mode of operation, the machine never halts, since the M9312 is sort of running a monitor. When under monitor control, it would make sense that the processor be at priority 7 so that no other devices could interrupt the monitor. Maybe on a machine with a real blinkenlights programers console, the PSW does not get reset to priority 7 on a halt, and so long as it is 6 or lower, the B0 version runs fine.

So, I inserted a NOP and CLR PS into the code (overwriting a little bit of code that I don't need to use that allows the user to set a nonstandard CSR, vector, and BR level). Now the B0 version is running good. (For the record, starting at location 002010, I deposited 000240, 005067, and 175760 as the patch. The maindec must be started at location 200 or 204 and NOT 210 since the patch destroyed the code called by 210)

Now we have to figure out why RT-11 doesn't work properly with the CT: handler. It must be a software problem, since all the hardware maindecs now pass.

Lou

Lou - N2MIY
November 20th, 2010, 06:40 PM
Well, it works under RT-11 V4.0 at least. I can now read and write TU60 tapes on both the 11/04 and the 8/e.

Somehow the CT: handler seems to have gotten broken between RT-11 V4.0 and V5. That will take some looking into.

Lou

Lou - N2MIY
April 10th, 2011, 12:10 PM
As a final bit of insanity for this project, I have installed a UDA50 for connecting RA series SDI drives.

I would now call this project complete.

The 11/04 has a full 32kW of core (maximum supported for 11/04) and these perhiperals:

RX11 / RX01 8" dual floppy
RL11 / RL01 and RL02 drives
TA11 / TU60 Cassette
UDA50 / RA80 (shared with the 11/53, RA80 is dual ported)
DEUNA Ethernet
DL11 / Emulated TU58
DL11 / for the console terminal

It's mounted at the top of a five foot rack with the RX and RL drives. Final picture is here: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=5577

Lou

RSX11M+
April 10th, 2011, 02:49 PM
As a final bit of insanity fot this project, I have installed a UDA50 for connecting RA series SDI drives.

Ummm.... ya. Totally agree.

NeXT
April 10th, 2011, 03:14 PM
What's wrong with RA drives besides being non removable?

Lou - N2MIY
April 10th, 2011, 05:12 PM
The insane part is putting a UDA50 on an 11/04. I wasn't even sure it would work. The only weaker unibus processor is an 11/20.

Does anyone have any spare MSCP boot roms for an M9312 unibus bootstrap card?

Lou

RSX11M+
April 10th, 2011, 07:14 PM
The insane part is putting a UDA50 on an 11/04....

Makes me gigle.... a little like stuffing a Hemi in a VW Beetle.


Does anyone have any spare MSCP boot roms for an M9312 unibus bootstrap card?

Lou
Believe it or not.... Look here (http://bitsavers.informatik.uni-stuttgart.de/bits/DEC/pdp11/M9312/index.html) - The file should be 767A9.BIN if I'm reading this right.

Here's another (http://www.slowdeath.com/AK6DN/PDP-11/M9312/index.html) - Includes Listing. This guy was pretty impressive.

pontus
April 10th, 2011, 11:10 PM
uhm.. Wow! That is one anachronistic set of racks you have there. I do like the PDP-8/e in the VAX cabinet :D

Can you access the RA80 concurrently from both PDPs?

Is that a kitchen tabletop on the left rack?

I'm butchering a rack just like it (I have to, no space, no takers). Would you like the parts missing from your rack? Free of course, but shipping is on you.

Lou - N2MIY
April 11th, 2011, 05:35 PM
Pontus,

No, both machines can't work with the drive at the same time. I have the 11/53 connected to port A and 11/04 to port B. It may be an RT-11 thing, but once a machine gets control of the drive, the other is locked out, until I release the RA80 front panel button for the machine that has control. Then, the other machine can get control until I release its button and press the other one. So, I can't get both the A and B front panel lamps lit at the same time. Maybe someone else who has tried to connect two machines to one SDI drive can comment on how it's supposed to work.

I think the dual porting on SDI drives was intended for redundnacy. A customer could have two VAXes connected to a drive so that when one VAX failed, the other could pick up the duty. I'm not sure that the intention was to have two independant systems, each with their own jobs, sharing one drive (my setup).

Yes, that's a bit of kitchen countertop under the 11/53. It was left over from when I did my laundry room. A close eye will see that it matches the counter that shows up in some pictures of activities at my indoor "bench".

If you were on this side of the pond, I would gladly give your rack a good home. Cutting one up as a scrap is terrible. If you are considering doing that then you don't nearly have enough junk lying around your place (or else the rack would be full already). I could easily fill up two more of those racks if anyone in metro NYC has them to give away!

Lou

pontus
April 11th, 2011, 10:27 PM
I have already used parts from the rack to complete the rack for my 11/44. So it's going to be cut up anyway I'm afraid. I simply can't fit it in with all my other stuff. I know I will regret this in a few years time :/

RSX11M+
April 12th, 2011, 07:23 AM
OUCH.

Crying now.

Lou - N2MIY
April 12th, 2011, 05:31 PM
Pontus,

I just looked at your website and you certainly do have more than enough room for that rack. You do not have crap piled in front of crap yet. You can still walk in that room and not step on anything. It looks too neat and organized.

If you insist on keeping everything that tidy, I have a suggestion. Put shelves inside the rack and take down some of your shelving units, then roll the rack where the shelves were.

Lou

Lou - N2MIY
November 11th, 2011, 04:39 PM
Hardware junkies might enjoy this....

I was recently reviving CAPS-11 if anyone has been reading alt.sys.pdp11 with this 11/04 that we built from parts. However, the secondary bootstrap for CAPS-11 examines the switch register but I didn't have a proper programmer's console for this machine, only the operator's console I wire wrapped. CAPS-11 can't load without a switch register!

So, I made my own switch register. See here: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=7062 with a closeup of the switches here: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=7063

I made a double height interface that plugs into a MUB slot and puts the contents of the newly added front panel switches at 177570 (the switch register address). The logic is most of an M104 address selector plus some bus drivers. The schematic is here: http://www.vintage-computer.com/vcforum/album.php?albumid=77&attachmentid=7061 Yes, I used real DEC380 for the bus receivers, but cheesed out and used 7438 for transmitters (instead of 8881).

I do now have CAPS-11 running and have sent the copies of the bootable tapes and sources to the appropriate archivists. That discussion is over on alt.sys.pdp11, but I thought folks here might enjoy the switch register sub-project.

Lou

tingo
November 13th, 2011, 03:36 AM
Well done!
For what purpose does CAPS-11 examine the switch register?
(yes, I know, I'm curious - always.)

pontus
November 13th, 2011, 09:05 AM
Now that is just gorgeous! I wish I had you skill set, well done!

Lou - N2MIY
November 13th, 2011, 01:48 PM
In CAPS-11, the secondary loader loads an absolute loader that looks at the switch register. It examines the LSB to see if it should load the next file (the monitor) from the address at the beginning of the file, or relocate to the address provided. I have no idea why this was necessary, as I have not yet seen the CAPS-11 manuals. However, with no switch register at all, the loader fails. There is a gentleman in Australia who has the CAPS-11 manuals and will scan them as he finds the time. I am in no hurry....

As for having a "skill set" well, I am sure anyone could do what I did. I made that switch register label in M$ Excel and printed it on a color inkjet printer. I used it as a template to mark the holes for the switches, then hand drilled starter holes and finished the holes on my drill press. The label front is covered with self adhesive laminating film, and the back is held to the panel with double stick tape. There is really no special skill required.

Lou

tingo
November 21st, 2011, 02:01 PM
In CAPS-11, the secondary loader loads an absolute loader that looks at the switch register. It examines the LSB to see if it should load the next file (the monitor) from the address at the beginning of the file, or relocate to the address provided. I have no idea why this was necessary, as I have not yet seen the CAPS-11 manuals.
Hmm, perhaps to be able to load "next file" into memory without overwriting current contents?
(I'm only speculating here)

Lou - N2MIY
November 22nd, 2011, 02:58 AM
I think how this happened was that a big chunk of code was reused. In the source files for CAPS-11 I found the cassette absolute loader by itself. When I disassembled the secondary loader (the first file on a bootable cassette, CTLOAD.SYS), it had two parts. The first part (which I could not find source code for, but no big deal, it's simple anyway) is executed after the bootstrap loader brings in the first 200 (octal) words of the secondary loader file. Those 200 words then load the rest of the secondary loader file, which is the absolute loader used to bring in the next file on the tape (CAPS11.S8K, the monitor). Rather than bother doing anything, the absolute loader was used as-is. Which is no big deal - unless you have no switch register (but then, if not, dec got to sell you one!)

To your point Tingo, I am sure that when the absolute loader is used for other things, the intent is as you thought.


Hmm, perhaps to be able to load "next file" into memory without overwriting current contents?
(I'm only speculating here)


Lou

tradde
November 22nd, 2011, 02:13 PM
Beautiful Lou. You are the man. Someday I plan to get up there and see all your stuff.

Lou - N2MIY
November 22nd, 2011, 03:50 PM
Tim,

Well, thank you. I'm glad to have been able to do so much with the parts you gave me. When you come up for a visit I will point out all the bits that were previously in your basement. There is a VT340 waiting here for you. There really isn't a whole lot to see (compared to your old setup!), but what I do have does get played with (the dec stuff anyway.)

Lou

Lou - N2MIY
November 23rd, 2011, 04:05 PM
Guys,

You have got to see this: http://porkrind.org/missives/the-core-memory-module-from-my-dads-homebuilt-pdp-1105/ . This kid's dad is my wire-wrapping idol !!!!

Lou

pontus
November 23rd, 2011, 10:11 PM
I saw that one. Absolutely mind blowing!

RSX11M+
November 24th, 2011, 11:33 AM
A man with that much patience should be given the schematics and wire lists to a KA10. I'd bet there's 10 lbs of silver in all that Kynar Wire. The sockets cost more than the parts, and real estate to put it all on isn't cheap either.

He'd definitely win every award going at a hobbyist show.

MikeS
November 24th, 2011, 12:41 PM
...He'd definitely win every award going at a hobbyist show.An awesome project, to be sure, but he'd have a little competition:
http://www.youtube.com/watch?v=n3wPBcmSb2U
and
http://www.electronixandmore.com/project/relaycomputertwo/
And then there's my favourite:
http://nablaman.com/relay/

Never mind 'clicky' keyboards ;-)

JGardner
November 24th, 2011, 05:54 PM
Wow...

Jack