[cctalk] Re: Old Professional/350 software, any of this out there
On 7/29/2023 12:36 PM, emanuel stiebler wrote: On 2023-07-29 13:57, Bjoren Davis via cctalk wrote: I never made a push to publish it because by the time I got to it the parts (Cypress CY62167G-45ZXI SRAM and ATF1504AS-10AU100 CPLD) had become unobtainable. The SRAM can still be find, but the CPLD? Any chance to replace it with something newer? Possibly. This was only the 2nd PCB I ever designed, so I was very conservative and used a CPLD. Now that the logic has been proven, I'm sure the board could be reworked using just 5V-compatible flip-flops, discrete logic, and a latch. As far as using the board as it is: I think the only other possible CPLD that would work would be the 25 ns version ATF1504ASL-25AU100. I think that's still plenty fast enough, but it seems to be just as hard to get as the original. Maybe things have changed, but right now there are only 3 of these boards. I have 2 and I think I sent the 3rd to you, Paul. Any chance you like to have a look at it again? Sure, I guess. As I mentioned I think the best thing would be to rework it with discrete logic so as to really reduce the susceptibility to future shortages. Even if it increases BOM and assembly costs. The problem with reworking the board with a different CPLD is that it needs to be a 5V-compatible CPLD, and it needs to be able to buffer half of the address lines (9 in and 20 out). That means it needs a high pin count. These two criteria quickly narrow the possibilities down to almost nothing. Add to that the wanting a reasonable price and availability for a few years and it really does go to nothing.. Digikey claims that the ATF1504AS-10AU100 is still an Active product and expects new product in April, 2024. Maybe it just makes sense to wait?
[cctalk] Re: Old Professional/350 software, any of this out there
Paul, A couple of years ago I did design and build a new daughterboard with modern SRAM that supports up to 2 MiB of RAM on the PC/380 and up to 512 KiB on the PC/350. https://oshpark.com/shared_projects/eBNkBw8x It even works. I never made a push to publish it because by the time I got to it the parts (Cypress CY62167G-45ZXI SRAM and ATF1504AS-10AU100 CPLD) had become unobtainable. Maybe things have changed, but right now there are only 3 of these boards. I have 2 and I think I sent the 3rd to you, Paul. --Bjoren On 7/29/2023 10:36 AM, Paul Koning via cctalk wrote: On Jul 29, 2023, at 12:45 PM, Chris Zach via cctalk wrote: Answering my own question: Yes it does work. My Pro/380 now sees 320kw of memory instead of 256kw. Now to buy some sockets and upgrade these boards to 256kw each. One can go in the Pro/350 and the other plus the memory boards should take my Pro/380 to almost 1kw. I wonder if the CTI memory boards can be upgraded from 64k chips to 256k chips. Probably would require reprogramming the ROM as well on the board. Hm. The Pro Technical Manual (on Bitsavers) answers a bunch of these questions. If I remember right, the 380 will accept 350 memory daugher cards but also larger-capacity cards (bigger chips) that are 380 only. Also, the wiring for the board allows for larger memories than what DEC actually built; the details are in the CPU/Motherboard chapter of the manual. And/or in the schematics. I've thought about building such a daughtercard, I think the best case allows close to full 4 MB worth of memory. paul
[cctalk] Looking for information on Data General 602X magtape drive
Hello CCtalk, I recently bought the mortal remains of a Data General 602X magtape drive on craigslist. Apparently it had been stored outside. When I got it it had mudwasp nests and mud all over it and everything that could rust had. When it was decomissioned it was just cut out, so it's missing its chassis, hinges, controller board, power supplies, vacuum blower, vacuum pressure limit switches, etc. The cables to the heads are just cut (no connectors). But boy does it look cool, and it *does* have all three of its transport motors and its console PCB. There's very little identifying information on the drive. The front of the drive has a label "9 TRACK 800 BPI". The console PCB says "COPYRIGHT © 1973 BY DATA GENERAL CORP" "CONTROL BOARD FOR 75 I.P.S. DRIVE DGC NOVA 107-000275-17 /16" and has a sticker on the back "DRAWING NO. REV. 005-005-525-02 005-001-743-11". The date codes on the few chips I can read place it from 1976. I think all of this adds up to this being a model 6021 or 6023. I've been slowly disassembling, cleaning, and repairing it. The DG documentation at bitsavers is really good, but, sadly, the schematics are not available there. Does anyone have such schematics? I'm especially interested in the analog portion that connects to the heads, the connection to the BOT/EOT sensor, and a schematic for the console board I actually do have. My goal is to replace all of the missing controller parts with some SOC boards (e.g., a Teensy 4.1), ultimately to be able to use this drive to read and write tapes. I'd love to reuse the console board as it is. I've already replaced the vacuum blower with a $30 Bosch vacuum cleaner I also bought on craigslist. Thanks. --Bjoren
[cctalk] Re: Using Gotek's to emulate RX50's.
Chris, I, too, tried a similar thing. It mostly worked until there was a need to switch quickly between the two drives (booting the diagnostics, for example). Then it worked strangely. What I believe may be going on is that the Pro is relying on the fact that, although there appear to be 2 drives attached, they are using the same head positioning -- they seek in parallel. I thought about hacking the Flashfloppy code to pay attention to the drive select and allow a single Gotek to emulate both drives (and take into account the parallel seeking), but I just ended up using a real RX50 to boot diagnostics and that was good enough at the time. The big problem is that the Flashfloppy would need to have 2 disk images mounted at once. There's a problem of limited RAM in the Flashfloppy, but there's also a problem of the UI which is really set up for only a single image. --Bjoren On 3/2/2023 3:25 PM, Chris Zach via cctalk wrote: Seems like it should be simple, but it is not. I have a pair of Goteks with the Flaashfloppy code and each one has a USB with 400k RX50 images on it. Both are set to drive 2, and a standard 40 pin floppy crossover cable allows me to emulate a pair of drives. Now, I want to replace the RX50 drive on my Pro/380 with this setup to allow it to install POS. However it does not work, the Pro fails startup with an error on the floppy controller board, and so far it looks like POS can't see the disks. So what is the difference between an RX50 and a pair of 5.25 drives, and is it possible for Flashfloppy to emulate whatever oddness is in a true rx50? CZ
[cctalk] Re: Pertec controller; was: anybody need 1/2" tape drives?
Hello Chuck and Jay, I took this off list because I'm not sure people would be interested. I made a simple board with level shifters to allow me to use a PJRC Teensy 4.1 (https://www.pjrc.com/store/teensy41.html) with a Pertec interface. I called it a "Pertexus". The Teensy is really nice because it's actually available, relatively cheap, and has Ethernet. The firmware I wrote creates a simple USB "serial" command line interface which allows me to read tapes to files on the SD card, write tape images from the SD card, and do a bunch of hairy diagnostic things. I've only tested it with my Qualstar 1052 drive. In theory the setup could be used to emulate a drive, but I haven't actually tried that. Is this interesting to you? Thanks. --Bjoren On 11/29/2022 6:21 PM, Chuck Guzis via cctalk wrote: On 11/29/22 13:31, Jay Jaeger via cctalk wrote: I very much care; indeed I had thoughts of maybe doing something similar, using a BeagleBone, but this sounds a lot easier. Would like to know exactly what board you chose, so I can acquire one. I have a cipher drive and an HP 88780A that would be good candidates to use with this / use this to test. I also have a DG drive that might well have a Pertec interface (haven't looked in a while). Hi Jay, The board I'm using is the STM32F4VE, described here: https://stm32-base.org/boards/STM32F407VET6-STM32-F4VE-V2.0 Cheap and available; generally about $14-15 from Aliexpress. I've toyed with the STM32H750 board (very similar, but runs at 400Mhz; the added cost didn't contribute anything toward functionality. Your DG might well be Pertec-interface, but you can check that out with Bruce Ray. Oh, a word of caution is in order... With the chip shortage, a lot of Chinese vendors are re-labeling GDS32F407 and CKS32F407 chips with the ST logo and markings. I've run into a few, but generally, they perform as well as--and in some cases, better than, the real thing. I'll put you on my mailing list... All the best, Chuck
[cctalk] Re: MicroVAX CTI (DEC Professional) card
On 9/9/2022 5:39 PM, Warner Losh via cctalk wrote: On Fri, Sep 9, 2022, 3:24 PM Lee Gleason via cctalk wrote: Took some pictures of the MicroVAX CTI card, and another odd card I got - an 8086 CTI smartcard. See 'em both at https://rsx11.blogspot.com/2022/09/microvax-and-8086-smartcards-for-dec.html The 8086 card was likely for DOS or CP/M-86 programs... It likely predates windows and didn't seem to have graphics parts / output (though I suppose the latter could be over the bus...) I have one of the Virtual Microsystems PC-Bridge CTI boards (the commercial 8086 board). One of the more interesting things about it is that it has its own video circuitry. It's built up around an Hitachi HD46505/HD6845 CRT controller with 16 KiByte of video RAM and a character generator ROM (a lot like a CGA). The board has one of the "long" ZIF connectors with the additional 30 pins which carry, among other things, the analog video signals wired directly to the monitor port. The board superimposes its own video onto that of the system. The PC-Bridge host software just clears the screen and turns off the cursor. In some cases the host software can pop up host video simultaneously with the PC-Bridge video. I assume the PC-Bridge hardware looks for sync on the "GREEN VIDEO" signal or, possibly, the driver software uses the host video sync interrupts to do a kind of software PLL to lock the video sources together. Somehow the fact that both the system and the PC-Bridge board simultaneously drive the analog video lines works out. Hairy stuff. Another really interesting thing about the PC-Bridge board is that it has DEC-labelled parts on it. I'm not talking about things like "proprietary" bus interfaces chips. The DRAM SIMMs (used for the board's main memory) have the digital logo and a DEC part number on them (1418744-00). In addition the chips are labelled with the DEC convention (Exx) and are numbered E1, E2,... starting in the lower right hand corner, with the first chip of each column being labelled on the board, just as on DEC boards. This made me suspect that the PC-Bridge board was actually designed by DEC, or maybe the design was originated by DEC, and so maybe the board Lee got on eBay was an earlier version of the PC-Bridge. But it's clear that isn't the case -- Lee's board has a 60-pin ZIF connector and no apparent CRT controller chip. I was never able to get the original Virtual Microsystems software package for my board, but from a friend I did find a Pro hard drive image with the PC-Bridge application software installed on it. With that I was able to regenerate the installation diskettes. All of this is an incredibly roundabout way of saying: I was going to offer my reconstituted PC-Bridge installation diskettes, but I really doubt they'll work. In fact, I really doubt the software to drive Lee's board is easily obtainable at all, given that his board bears no real resemblance to the PC-Bridge board which, AFAIK, was the only 8086 CTI board commercially available. From what I see in the photograph I'd guess that the board works much more like the DEC "CP/M" (Z80) board. In that case there's a simple mailbox register with interrupts wired up on both sides. When using the CP/M board the host is mostly just a dumb serial terminal with some side-channel floppy and file access. That's why there's no graphics at all with the CP/M board. --Bjoren
Re: MicroVAX CTI (DEC Professional) card
On 7/13/2022 3:02 AM, Paul Koning via cctalk wrote: Does anyone know anything about this card? Especially curious is the daughtercard connector: is it just for RAM expansion or is the daughtercard necessary for card operation? Daughtercard almost looks like a Pro memory board, but those were 16 bit and only 256kw in size if I recall. That's can't be enough to do anything useful. The standard ones, yes, but the connector and address wires supported up to a MW per board, perhaps even 2. It's mentioned in the Pro technical manual. I thought about building such a beast, never did. I actually did design and build such a board, and yes, it supports up to 2 MB (on the PC380 only). But the connector on the eBay board can't be a connector for a DEC Professional RAM daughtercard because it's the wrong gender and has too many positions. The DEC Pro RAM daughtercards also have header sockets, not pins, and they either have 40 positions (PC325/PC350) or 48 positions (PC380). The eBay board seems to have a connector with 2x32 = 64 positions. --Bjoren
MicroVAX CTI (DEC Professional) card
Hello Classic fans, Recently eBay seller smhelectronics261 posted a very interesting prototype board: https://www.ebay.com/itm/295087630609 The description is "Dec Digital PRO 350/380 Professional Microvax II Proto 54-16707 Collectors", and the board art mentions "MICROVAX SOFTCARD." Does anyone know anything about this card? Especially curious is the daughtercard connector: is it just for RAM expansion or is the daughtercard necessary for card operation? The photographs are fuzzy, but the more recent chip date I can see is 8536 (on one of the QFPs). This puts the board in the time period of the MicroVAX II development. The internal "MicroVAX Business Plan" (http://bitsavers.org/pdf/dec/vax/610/memos/Microvax_Business_Plan_Dec83.pdf) mentions a "Meteor" project (p. 11). It describes Meteor as: Meteor is Digital's first single-user MicroVAX product. Developed within Low End Engineering, the product is positioned as a strong competitor in the low end, technical/scientific and the high end office/business graphics workstation market. Meteor should be an effective follow-on product to the Professional Series and high end VAX/Seahorse workstations. Although not a replacement product per se, Meteor represents a clear migration path for PRO users upward in functionality, and for VAX Workstation applications downward to a lower cost, single user design. Does anyone know if this board is Meteor? I'll be bidding on the board, but given how pricey CTI boards have gotten recently (a DECNA card from the same seller recently sold for $422.99), I probably won't win. If the winner of the auction reads this, could they please contact me? I'd like to collect an image of the boot ROM from the board, if possible. Thanks. --Bjoren
DEC RX50 mysterious 81st cylinder
Hello Retroovers, Here's something interesting that Oleksii in Ukraine discovered. While playing with a Fluxengine, he found that some RX50s have data, stored in FM format, in a single sector the 81st track of the diskette. For fun I went through my collection of original DEC distribution diskettes for the DEC Professional, read the single sector and compared them. Here is what I found: Common data (locations with variations marked with __): 00: 46 4d 54 20 4d 46 4d 20 4e 4f 2f 46 43 20 31 2a |FMT MFM NO/FC 1*| 10: 31 30 2a 35 31 32 20 38 30 54 20 2d 44 45 43 20 |10*512 80T -DEC | 20: 52 58 35 30 00 20 20 20 32 32 32 36 34 2d 32 33 |RX50. 22264-23| 30: 20 20 __ __ 84 __ __ __ 20 46 01 f5 30 30 __ 30 | __.___ F..00_0| 40: __ __ __ 20 20 20 20 20 20 20 20 20 20 20 20 20 |___ | 50: 20 20 20 20 82 f1 c8 54 9a fd ce 57 9b 7d 0e b7 | ...T...W.}..| 60: 6b 05 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |k. | 70: 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | | Variations: offset 32 33 35 36 37 3e 40 41 42 file --- BL-AI19C-BH 04 02 10 34 19 30 31 35 30 BL-CF74C-BH 03 26 00 01 36 30 30 39 30 BL-CF74C-BH 03 26 00 03 45 30 30 39 30 BL-CL73B-BH 11 10 00 53 44 30 30 37 31 BL-HC42A-BH 04 09 19 59 54 30 31 33 30 BL-HD04A-BH 01 21 17 26 09 30 31 34 30 BL-HD04B-BH 01 07 11 34 01 30 30 f3 31 BL-HD04B-BH 06 18 02 24 01 30 30 31 30 BL-HD05A-BH 01 22 02 33 40 30 32 30 31 BL-HD05B-BH 02 11 19 59 51 30 30 30 31 BL-HD05B-BH 02 11 20 00 55 30 30 30 31 BL-HD06A-BH 01 03 13 31 10 30 30 34 30 BL-HD06B-BH 06 18 05 08 58 30 30 35 31 BL-HD06B-BH 06 18 05 07 54 30 30 35 31 BL-HD07B-BH 06 18 01 42 23 30 31 38 30 BL-HD07B-BH 06 18 01 43 28 30 31 38 30 BL-HD07B-BH 01 07 12 22 22 30 30 f3 31 BL-HD08B-BH 01 07 13 51 38 30 30 f3 30 BL-HD08B-BH 01 19 12 45 32 30 31 38 30 BL-HD08B-BH 01 07 13 52 42 30 30 f3 30 BL-HD09B-BH 01 07 13 05 38 30 30 f3 31 BL-HD09B-BH 01 17 05 34 48 30 31 39 30 BL-HD09B-BH 01 07 13 04 33 30 30 f3 31 BL-HD10B-BH 06 18 09 43 45 30 30 35 30 BL-HD10B-BH 06 18 05 45 16 30 31 39 30 BL-HD10B-BH 01 20 19 22 06 30 30 30 31 BL-HD11B-BH 01 17 06 05 36 30 30 31 31 BL-HD11B-BH 01 17 06 06 41 30 30 31 31 BL-JB90B-BH 06 17 14 45 00 30 31 31 30 BL-JB90B-BH 06 18 12 29 42 30 32 30 30 BL-JB90B-BH 06 17 14 46 03 30 31 31 30 BL-JB91B-BH 06 18 12 43 59 30 30 39 30 BL-JB91B-BH 01 13 12 01 21 30 30 30 30 BL-JB92B-BH 01 15 16 03 31 30 30 36 30 BL-KS73A-BH 06 04 09 36 40 30 30 30 30 BL-N596F-BH 01 03 10 09 00 30 31 31 30 BL-N596G-BH 07 03 18 02 08 34 39 36 31 BL-N605G-BH 02 13 01 12 58 30 32 30 31 BL-N631H-BH 12 16 15 41 36 30 31 33 30 BL-N631I-BH 01 19 10 28 32 30 30 35 30 BL-N633G-BH 12 11 03 48 40 30 30 32 30 BL-N633H-BH 03 05 14 21 50 30 30 33 30 BL-N634G-BH 07 03 17 00 26 30 30 31 30 BL-N638F-BH 12 05 19 13 38 30 31 32 31 BL-N639H-BH 03 26 02 32 50 30 30 39 30 BL-N640G-BH 03 26 00 59 57 30 30 31 30 BL-N640G-BH 03 26 04 41 36 30 30 34 30 BL-V444B-BH 12 13 02 51 00 30 31 34 30 BL-Y472B-BH 03 20 08 21 38 30 31 32 31 BL-Y982D-BH 03 05 20 02 57 30 31 39 30 BL-Y982D-BH 07 03 15 48 31 30 30 37 31 BL-Z934D-BH 04 10 04 16 13 30 30 33 30 --- MIN 01 02 00 00 00 30 30 30 30 MAX 12 26 20 59 59 34 39 f3 31 NVALS 08 12 14 22 21 02 04 0b 02 OR 17 3f 3f 7f 7f 34 3b ff 31 AND 00 00 00 00 00 30 30 30 30 Key MIN is the minimum value seen MAX is the maximum value seen NVALS is the count of unique values seen OR values have a 1 for every bit that is ever 1 AND values have a 1 for every bit that is always 1 Some interesting things to note: * only some diskettes have 81st cylinder data. They tend to be the later releases (1985 and later). (My table simply omits those diskettes I have without 81st cylinder data). * different copies of the same diskette (e.g., BL-HD11B-BH) have slightly different values, so it doesn't appear that these value encode some kind of master ID. * the values at offsets 0x32, 0x33, 0x35, 0x36, 0x37 appear to be BCD-encoded month, day-of-month, hour (0..23), minute, and second. Logically, this would mean that the value at 0x34 should be the BCD-encoded year, but it's always 0x84, and most of these diskettes
interesting DEC Pro stuff on eBay
Hello Retronians, I just saw some interesting DEC Professional items on eBay from smhelectronics261 (https://www.ebay.com/sch/smhelectronics261/m.html): 1. Pro-350 (and presumably -325) video board https://www.ebay.com/itm/294933607768 2. RD (hard disk) controller https://www.ebay.com/itm/294933620853 3. CTI RAM board https://www.ebay.com/itm/294933515548 4. RAM daughtercards https://www.ebay.com/itm/294933505973. The description says "This added 512MB or Ram" but I think it is mistaken. The boards are marked "5415084" which I believe is the 2-layer version of the board populated with 64 Kibit DRAMS, for a total of 128 KiByte/board or 256 KiByte for both boards (assuming that's actually what they're selling). 5. Something called a "DEC Digital Professional DMA tester diagnostic module Pro350" board https://www.ebay.com/itm/294933577848. I've bought from this seller before and they seem to have had access to DEC-internal development stuff. I bought a prototype TMS board and a prototype never-released high speed serial board from them. #5 is especially interesting because, as far as I know, no production CTI board ever did DMA (not even the disk and Ethernet controllers, to everyone's disappointment). Looking at the photo I see the name "Dave Iacobone". I wonder if he is still around and remembers that board. Just FYI: I, too, might bid on some of these items, but I thought it'd only be fair to let everyone know. --Bjoren
Replacement BOT/EOT markers for 1/2" tape
Hello Retrofolks, I have a 1/2" 9-track magtape which is missing a BOT marker. Does anyone have a recommendation for a reflective tape to use to replace the BOT marker? I was looking at https://www.amazon.com/Metalized-Polyester-Adhesive-Multiple-Available/dp/B07TXN8TD8, but I have no idea if it's too stiff/thick/not sticky enough/etc. Thanks. --Bjoren
Re: Question about DECtape formulation
On 1/25/2022 9:18 AM, Paul Koning via cctalk wrote:
On Jan 24, 2022, at 10:27 PM, Gary Oliver via cctech
wrote:
...
As to the real reason I was doing this: Most of my tapes are un-boxed and have suffered
being in a dusty area (before I got them) with the dust forming a sort of 'crust' on the
outside of the tape. It's only on the first wrap or so, but it's enough that it keeps
those handy vinyl cohesive tapes from sticking. For that reason, I was trying to find
something to clean of this dusty gunk so the vinyl strip would hold the tape into a
spooled condition. It was the side-effect of this effort that lead me to the discovery if
this "removable layer" on the DECtape.
BTW, does anyone know of a source for these vinyl strips. My old ones are 10 mil blue
very-flexible vinyl without any adhesive. They rely only on the cohesive properties of
vinyl-to-a-non-porous surface. I tried using some of the 'dry vinyl' sheets from Cricut
(the plastic decal printer company.) They have a couple of colors without adhesive that
they call "window cling" but they aree only 4 mills thick and a bit flimsy,
though so-far they are holding ok.
There's a children's toy I remember: shapes cut from vinyl, intended to be
stuck to windows to make pictures. That seems to be the same stuff.
paul
Paul,
Are you thinking of Colorforms (https://en.wikipedia.org/wiki/Colorforms)?
To answer Gary's original question: I did find something at
McMaster-Carr: https://www.mcmaster.com/catalog/128/3973 ("Clear
Static-Cling Chemical-Resistant PVC Film").
I don't have any personal experience with it, and it's only 0.007"
thick, so it may not meet Gary's needs.
But if anyone has used it before for tapes I'd love to know if it works
well.
--Bjoren
Re: Documentation for F11 Chipset?
[ off list ] Rob, Did you get my response to your question? Was it helpful? Do you have more questions? BTW I'm back at my home so I can instrument my machine again. --Bjoren On 5/16/2021 9:56 AM, Bjoren Davis via cctalk wrote: I have been looking at this and I think you are right. But the reason is odd. It looks like the ROMs are never being selected by the ROM address decode. I can't find on the printset anything that says what the boot address would be, perhaps that is burned into the F11 chipset? However, from the Pro technical manual the ROM addresses are in the ranges 1773-17767776, so I think the top 7 bits of the address should all be 1s. It looks like I never get anything other than 0s, when the address strobe (CT6 RCV AS H on the printset) is asserted. There is activity on the F11 chips, so I think they are working. Any ideas anyone? Rob, The start address on the DEC Pro is physical address 01776. As a virtual addresses this is at the beginning of the I/O page (016). This mapping extends up 4 KiB (to physical 01776 or virtual 016). But, of course, the ROM is actually 16 KiB long. So where are the other 12 KiB? They're at physical addresses 01773..01775. These physical addresses are not mapped into virtual address space at reset, but the boot ROM does map them during its execution to exactly where you'd expect: 013..015. Now, just to top off this confusion, the mapping of CPU-perspective physical addresses to ROM address lines is a little odd. It's really best described a table, which I hope doesn't get mangled by email formatting (all values in octal): Virtual Physical ROM offset 013* 01773 03 013* 01773 03 014* 01774 00 014* 01774 00 015* 01775 01 015* 01775 01 016+ 01776 02 016+ 01776 02 * = mapped later by boot ROM into virtual address space + = low half of I/O page -- mapped at CPU reset time So you can see the low 14 bits of physical address are fed directly to the ROM. It makes for a slightly lumpy looking layout. The decode for this is on page CT10 of the schematic. You can see the "ROM ADDRESS DECODER" section which has a NAND of address lines 21..15 being used as an enable on a 3-to-8 negative-output decoder and a 3-input negative-input OR on outputs 3,4,5. This selects physical addresses 0177[3,4,5]. Then E114 decodes the I/O page locations when A12 is low (01776..01776). This is the crucial reset-time ROM selection decoder. As to why the CPU starts at 016...I swear I saw that once in the documentation somewhere but I can't immediately find it again. I believed that the CPU is presented with some kind of word at reset time that tells it where to start executing. I believe that you can see this word constructed by E3 and half of E17 on page CT2 of the schematic, but I can't find the documentation that describes the layout of the word. You can see the word would be 0b1110L010 where L is ~(CT2 LPOK 1 L) and X is undefined. Notice that the high bits decode to 016, and I think that's where the start address comes from. I hope that answers your question. --Bjoren
Re: Documentation for F11 Chipset?
I have been looking at this and I think you are right. But the reason is odd. It looks like the ROMs are never being selected by the ROM address decode. I can't find on the printset anything that says what the boot address would be, perhaps that is burned into the F11 chipset? However, from the Pro technical manual the ROM addresses are in the ranges 1773-17767776, so I think the top 7 bits of the address should all be 1s. It looks like I never get anything other than 0s, when the address strobe (CT6 RCV AS H on the printset) is asserted. There is activity on the F11 chips, so I think they are working. Any ideas anyone? Rob, The start address on the DEC Pro is physical address 01776. As a virtual addresses this is at the beginning of the I/O page (016). This mapping extends up 4 KiB (to physical 01776 or virtual 016). But, of course, the ROM is actually 16 KiB long. So where are the other 12 KiB? They're at physical addresses 01773..01775. These physical addresses are not mapped into virtual address space at reset, but the boot ROM does map them during its execution to exactly where you'd expect: 013..015. Now, just to top off this confusion, the mapping of CPU-perspective physical addresses to ROM address lines is a little odd. It's really best described a table, which I hope doesn't get mangled by email formatting (all values in octal): Virtual Physical ROM offset 013* 01773 03 013* 01773 03 014* 01774 00 014* 01774 00 015* 01775 01 015* 01775 01 016+ 01776 02 016+ 01776 02 * = mapped later by boot ROM into virtual address space + = low half of I/O page -- mapped at CPU reset time So you can see the low 14 bits of physical address are fed directly to the ROM. It makes for a slightly lumpy looking layout. The decode for this is on page CT10 of the schematic. You can see the "ROM ADDRESS DECODER" section which has a NAND of address lines 21..15 being used as an enable on a 3-to-8 negative-output decoder and a 3-input negative-input OR on outputs 3,4,5. This selects physical addresses 0177[3,4,5]. Then E114 decodes the I/O page locations when A12 is low (01776..01776). This is the crucial reset-time ROM selection decoder. As to why the CPU starts at 016...I swear I saw that once in the documentation somewhere but I can't immediately find it again. I believed that the CPU is presented with some kind of word at reset time that tells it where to start executing. I believe that you can see this word constructed by E3 and half of E17 on page CT2 of the schematic, but I can't find the documentation that describes the layout of the word. You can see the word would be 0b1110L010 where L is ~(CT2 LPOK 1 L) and X is undefined. Notice that the high bits decode to 016, and I think that's where the start address comes from. I hope that answers your question. --Bjoren
Re: Documentation for F11 Chipset?
Rob, Off list: I was wondering: you mentioned you have a printset for the machine. Is it the one from bitsavers or it is another? I ask because I'm the source of the one on bitsavers, but it is sadly missing the "MP-01483-00 PRINT SET RCX50" subset. I'm hoping someone has a printset that includes that piece. Do you have a different printset? Thanks. --Bjoren On 5/3/2021 6:19 AM, Rob Jarratt via cctalk wrote: I have gone back to trying to fix my DEC Professional 350. I have a printset for the machine now. I think the CPU is being constantly reset. Is there any documentation anywhere on the F11 chipset? Bitsavers only seems to have the later J11. Thanks Rob
Re: Documentation for F11 Chipset?
Hello Paul and Rob, The next thing I did was to hook up a logic analyzer to the address lines on the ROM. This told me how far I got with the boot sequence before it restarted. I disassembled the ROM and have some portions of it semi-decoded so that may be helpful. If you like I can send you the text file I have. Another helpful thing for me was to take the Xhomer emulator https://xhomer.isani.org/xhomer/ and instrument it to give me a "good" ROM boot sequence (correlated nicely with device accesses) and compare that with what I saw with my logic analyzer. That's how I figured out my ROM was failing to see an interrupt from the EPCI (I think the ROM was running the EPCI in loopback mode) and so it was resetting. I have to say: the POST on the PC3XX is impressively thorough, but the mechanism for reporting failures is absolutely atrocious (4 LEDs and, if you're lucky, a cryptic octal error code on the screen). I do have a functional 350 that I can instrument, so let me know if I can help. --Bjoren On 5/3/2021 2:29 PM, Paul Koning via cctalk wrote: On May 3, 2021, at 2:23 PM, Rob Jarratt via cctalk wrote: Sadly my machine is not at the point where I can attach a console of any kind. The CPU is being reset every 13us by a bus error. I am having trouble working out why though. I have got as far as working out that is the CT2 TIME OUT signal, but just why that is active isn't entirely clear to me. It would help to have a working machine to compare it to! Regards Rob That sounds like it's trying to access the boot ROM and not getting an answer. paul
Re: Documentation for F11 Chipset?
I recently brought a PC350 back from the dead. A good source of documentation for the F-11 is that for the 11/23 and 11/24 (e.g., http://bitsavers.org/pdf/dec/qbus/Digital_Microcomputer_Processor_Handbook_1979_80.pdf chapter 3 "LSI-11/23 Processor" or http://bitsavers.org/pdf/dec/pdp11/1124/EK-11024-TM-001_PDP11_24_System_Technical_Manual_Jun81.pdf) The first thing I'd do is to attach a "console terminal" cable (a cable attached to the printer port with pin 9 pulled to ground -- pin 8). DEC makes such a cable called BCC08 but I just made one myself. Then use a terminal program at 4800 to send a break and see if you get the ODT prompt. In my case I didn't get such a response. It turned out that the leaky battery had destroyed the "EPCI" at E155 (the async serial chip for the printer/console terminal port). I swapped the EPCI at E154 (the keyboard async serial chip) and I was able to at least talk to the ODT. I then bought a replacement EPCI on eBay and I was on my way. Good luck! --Bjoren On 5/3/2021 12:16 PM, Zane Healy via cctalk wrote: On May 3, 2021, at 3:19 AM, Rob Jarratt via cctalk wrote: I have gone back to trying to fix my DEC Professional 350. I have a printset for the machine now. I think the CPU is being constantly reset. Is there any documentation anywhere on the F11 chipset? Bitsavers only seems to have the later J11. Is the Sunsite archive still online? I seem to recall there being some documentation there. Zane
DEC CTI Bus Technical Manual, or looking for Ken Wellsch or Megan Gentry
Hello All, Does anyone have a copy of the DEC CTI Bus Technical Manual (EK-00CTI-TM-002) I can scan? If not, does anyone have an email address for Ken Wellsch or Megan Gentry as they both appear to be authorities on the CTI bus (see https://en.wikiversity.org/wiki/DEC_Professional_(computer)/Archive question 10)? Thanks in advance! --Bjoren Davis
DEC Professional: software and docs for CP/M and PC-Bridge boards
I have two oddball CTI boards for my DEC Professional: a DEC-made CP/M board (P/N 54-15641) and a board labelled "VIRTUAL MICROSYSTEMS PRO BD. REV 1" which appears to be an x86 MS-DOS board (it contains an 8086, a video controller and a bunch of RAM). I've managed to get them both functional, I believe, but I don't have software or documentation for either. I did find the RCS/RI diskettes at https://web.archive.org/web/20040113090630/http://starfish.rcsri.org/rcs/pdp-11/Professional/Pro-CPM/, but although the image files are uncorrupted it appears the diskettes were not read reliably in the first place. And I also know that at some point the PC-Bridge software and doc set was available on eBay (https://www.worthpoint.com/worthopedia/virtual-microsystems-pc-bridge-2-2005998357). Does anyone know where I can get a copy of the diskettes and/or documentation? Thanks. --Bjoren Davis
Re: DEC Pro 3xx archives
I had no problem expanding disk 177-20. I did it on a Linux system using wteledisk (which I got from https://github.com/jmechnich/wteledsk.git) using this script: for d in ~/downloads/decpro_software/ftp.update.uu.se/pub/professional/PRO* ; do newname=$(basename $d | tr [A-Z] [a-z]) mkdir decus/$newname cd decus/$newname for f in $d/*.lzh ; do lha -x $f done for f in *.td0 ; do ~/build/wteledsk/src/wteledsk $f -o`basename $f .td0`.dsk done cd ../.. done Here's what the files look like: $ ls -la build/pos32/decus/pro177/177-20.dsk downloads/decpro_software/ftp.update.uu.se/pub/professional/PRO177/177-20.lzh -rw--- 1 user group 409600 May 16 2020 build/pos32/decus/pro177/177-20.dsk -rw-r--r-- 1 user group 152827 Oct 22 1993 downloads/decpro_software/ftp.update.uu.se/pub/professional/PRO177/177-20.lzh $ md5sum build/pos32/decus/pro177/177-20.dsk downloads/decpro_software/ftp.update.uu.se/pub/professional/PRO177/177-20.lzh ca88b1d528dab3a5b3c1aaed1dd0f215 build/pos32/decus/pro177/177-20.dsk fae286c23044d1cac4d412c64afce0f6 downloads/decpro_software/ftp.update.uu.se/pub/professional/PRO177/177-20.lzh Did you possibly download a corrupted copy of 177-20.lzh? --Bjoren On 1/22/2021 11:09 AM, Warner Losh via cctalk wrote: On Fri, Jan 22, 2021 at 8:32 AM Paul Koning wrote: On Jan 21, 2021, at 11:20 PM, Warner Losh wrote: Hey Paul... This is really helpful. I've had to deal with those archives for the Rainbow stuff I do and have some additional caveats below I thought I'd share... Thanks for that information. Part of my motivation is that I mostly run Mac OS, and after that Linux -- not DOS let alone Windows. So I was hoping to find a Unix solution which is what I documented. dosbox runs on macos :). Now I have two additional questions. 1. In the PRO177 collection (P/OS 3.2 base system) the image 177-20 which is the ProSetupV32 disk seems to be bad. It converts fine, but the converted file is 160k, not 400k as it should be. If I pad it out with zeroes it still doesn't work, even though the data at the start looks plausible. Any advice? Is there a good one somewhere? Tim Shoppa's copy has the same issue. The DEC Robin/VT180 had a format that was 160k long. It's 1 side, 40 tracks, 8 sectors. Though I can't imagine it being valid in context... Have you tried the copies that are at https://www.digiater.nl/openvms/decus/vmslt02a/pro/ ? tar tvf 177-20.lzh -rw-rw-rw- 0 0 0 245921 Oct 22 1993 177-20.TD0 which suggests a 'normal' size to me... Though I've not decoded it, and it's possible the original was corrupt somehow... 2. The Xhomer P/OS image has Pro/DECnet installed, it seems, but it doesn't work. I see the floppies (5 of them) but no information on how to use them. Any information on Pro/DECnet install and setup anywhere? pro175 Pro/DECnet came up in my searches. It's also there. There's a pro175.txt that has: Following is a list of the manuals you will receive when you order Media Service Charge Code (EE): "PRO/DECnet User's Guide" "PRO/DECnet Problem Determination Guide" Notes: This program is also included on DECUS No. VS0112. Restrictions: A DECNA module is required to use the NET1 port on the rear of the system unit. Documentation available in hardcopy only. Sources not included. though I wasn't able to find it in the usual places, nor by searching for AA-V445A-TH which is the document ID number for the first one (I could just find references to it). Warner
Re: DEC Pro hard drive formatter
I should point out that, as far as I know, you can't use the floppy and hard disk emulation of the DREM-2 at the same time; it's one or the other. --Bjoren On 1/14/2021 8:59 PM, Cameron Kaiser via cctalk wrote: I've successfully used a DREM-2 (https://www.drem.info/) with my Pro 380 for both floppy and hard disk emulation. Cool! I just bought one of the G thingies ($30 on Amazon), will try loading up the modified firmware and see if it works. Just easier than making an endless pile of floppies I will only use once or twice (I already have the whole POS 2.0 set). Which firmware is this? The DREM-2 also interests me since I'd like to have a reproducible Venix install on my PRO 380 and it seems to handle both the floppy and HD side.
Re: DEC Pro hard drive formatter
I've successfully used a DREM-2 (https://www.drem.info/) with my Pro 380 for both floppy and hard disk emulation. --Bjoren On 1/14/2021 2:14 PM, Bill Gunshannon via cctalk wrote: On 1/14/21 1:52 PM, Paul Koning via cctalk wrote: On Jan 14, 2021, at 1:42 PM, Chris Zach wrote: ... Is there a hardware emulator that can emulate RX50's from images to a Pro? Been wondering that... Perhaps David Gesswein's MFM emulator could be modified to do that. You might ask him. I don't think it does so out of the box, though. The signal frequencies are much lower than those of hard drives. Some others make products that claim to offer the capability, https://www.drem.info is one (mentioned by David) and I also found this https://www.shopfloorautomations.com/hardware/floppy-connect/ . I know nothing about either. Standard PC floppy formats use 9 sectors per track but normal drives can handle 10-sector DEC formats too. If the emulators are done right they should handle that as well, but of course you'd have to confirm that. What about the GOTEK with modified firmware that they are talking about in other groups? bill
looking for advice on cleaning old equipment
Hello Classicquers, I have some vintage DEC equipment (terminals and small systems) that I need to clean up. I'm looking for advice on how to clean the plastic bits. Specifically, I want to know if anyone has a good solution to preserve labels that are attached to such plastic bits while they're being cleaned, especially labels that can't be removed (e.g., paper labels). In the past I've cut out pieces of Saran wrap just large enough to cover the label and then covered that with painter's masking tape. Unfortunately it wasn't perfect and some water/soap did get under the tape and reached the label (this is especially problematic if the plastic surface has some texture). I'm hoping for something like a wax or some other kind of material that is easily removed with heat but at room temperature is impervious to water and soap. Does anyone have any ideas, good or otherwise? Thanks! --Bjoren Davis
Re: Microsoft C 6.0 manuals
I have a retail boxed set "Microsoft Visual Studio 6.0 Professional Edition Upgrade" (P/N 659-00145). It's stuffed with CDs, some of which I seem to remember were sent to me after I mailed in some coupons. There's not much paper documentation -- a "Microsoft Visual Studio Resource Guide", "Getting Started Setup Guide for Visual Studio 6.0", "Visual Studio Developing for Windows and the Web", and some class library posters. The documentation appears to be on a 2 CD set "MSDN Library Visual Studio 6.0" (P/N X03-73112 or possibly X03-55262). There is a card "Getting Started with Microsoft Visual Studio 6.0" which says: "The MSDN compact discs include a complete documentation set for Visual Studio and for each of the core products." --Bjoren On 10/7/2020 11:29 AM, Chuck Guzis via cctalk wrote: On 10/7/20 7:23 AM, Tomas By via cctalk wrote: On Wed, 07 Oct 2020 16:18:15 +0200, wrote: Would then not be on MSDN cds from around that time? I don't think so. I did spend some effort to locate on of those that I had some reference to, but it turned out to be nothing. (And I have checked at least ten MSDN CDs for this material.) There are paper copies in some west coast US libraries, but I have not yet gotten desperate enough to try that route. I don't know if I hung onto the MSC 6.0 manuals, but am looking at what amounts to a sizeable portion of a bookshelf that deals with 7.0. That's a lot of paper. Just the "Comprehensive Index and Errors" book looks to be somewhere around 400-500 pages. I don't believe that MSC was part of MSDN back then. At least I don't recall seeing it on my CD collection, although ISTR that there were services packs for it there. FWIW, --Chuck
Re: Pro 350 Print Set
On 20/10/2019 17:27, Rob Jarratt via cctalk wrote: >/Manx lists MP-01394-00 as the Field Maintenance Print Set for the DEC />/Professional 350. I can't find this online and I was wondering if anyone has />/a scan of it by any chance? />//>//The Field Maintenance Print Set for the Professional 380 is available on Bitsavers along with some technical manuals for the Professional 350: http://www.bitsavers.org/pdf/dec/pdp11/pro3xx/ This might give you at least part of what you need. Matt Hello Rob, I know this is an old, old thread (I don't know what the etiquette about dead threads is) but you might like to know that I bought a copy of MP-01394 (the DEC Professional 350 Field Maintenance Print Set) and scanned it. Al Kossow was kind enough to post a compressed version on bitsavers: http://bitsavers.org/pdf/dec/pdp11/pro3xx/MP-01394_PC350_Field_Maintenance_Print_Set_.pdf --Bjoren
Re: Thoughts on restricted distribution documents (Dec Professional 350)
If it helps, I bought a copy of the DEC Professional 350 Field Maintenance Print Set (MP-01394) on eBay a few months back. I've scanned it but I've been waffling about where to post it. Scanned @600DPI with lossless compression it's huge: 1 GB. Saved as an "optimized" PDF (with very little visible difference) it's 94 MB. In the short term I've temporarily thrown up the optimized copy onto Google drive: https://drive.google.com/file/d/1BHpaneWpvWTO4UXUhLRgNV09rIiWTf3P/view I'd love to be able to contribute this to something like bitsavers. Thanks. --Bjoren Davis On 9/29/2020 4:48 PM, Paul Koning via cctalk wrote: On Sep 29, 2020, at 4:29 PM, Chris Zach via cctalk wrote: Makes sense. Still it's uncompressed so pretty big. I'll need to work on cleaning up the scans a bit, then I'll put the Tiffs up for download/whatever. Just don't want a lot of copies, consider that pdf as a proof of concept to review. TIFF supports compression, in a number of different schemes. LZW tends to work well for gray and RGB; the CCITT schemes are for bitonal (black/white bitmap). All TIFF compressions are lossless so they are all safe for material of all types. Is what you posted the whole document you have, or are there others? I was really hoping for the "CT bus manual". I did see interesting stuff in this one, though; for example, the first documentation I've seen of the hard drive FORMAT command. paul
