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Re: pdp-10 fpga [message #6474 is a reply to message #6472] Sat, 24 August 2019 23:29 Go to previous messageGo to next message
ale500 is currently offline  ale500
Messages: 44
Registered: April 2018
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I haven't made much more progress yet since a friend of mine borrowed the board I bought for this project Sad. I have some other possible targets, like a DE0-Nano and a DE10-Lite, but they are Altera-based boards.
Anyways I am really liking Rob's approach of using a Spartan3E module (you can get off aliexpress SmileWink
@Rob: would you post your Kicad or gerber files so we could also order some boards ?
Re: pdp-10 fpga [message #6636 is a reply to message #6474] Mon, 07 October 2019 18:48 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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Well, it time for an update on this. I've got all of the hardware basically working. I can successfully telnet into the board via its network interface (see last screenshot), and the serial console works fine. So the FPGA clocking, RAM, Serial ROM and IDE/CF interface all checkout. The only Verilog I've changed is around generating the clocks from the 50 MHz oscillator on the FPGA board.

The DS1337 RTC chip seems to work from a hardware perspective in that I can write to it, read those values from it, and see that the values stored are retained across a power-cycle via battery. But I don't understand the values that ITS is writing to it, and ITS does not seem to read from it at boot time, so I have to manually set the time on a reboot.

On the network side, I can't telnet out (at least) because the TELNET binary is missing on the disk image I have, and some of the CHAOSNET stuff that Conroy shows on his screenshots on his writeup does not work for me. But I don't think these are hardware problems, but rather software ones and/or my lackof understanding how to get them to work.

Also for reasons as yet unknown the usual ITS shutdown sequence does not work.

I made a few hardware blunders on this prototype, so I'm doing another spin of the board, while making some changes to make it usable as a Multicomp system also (adding an SD card interface for sure, maybe VGA and PS/2 by reusing the pins of Ethernet interface that aren't usable in a Multicomp system).

Once I get this next iteration of the board debugged, I'll post the schematics, KiCad files, etc. on a builderpage.

Conroy has a few screenshots on his writeup as he debugged his original board. Here are some of the equivalent screenshots for my version of the board.

Initial boot, zeroing out and displaying some memory. This shows basic PDP10 instructions running to get to this point.
/forum/index.php?t=getfile&id=1533&private=0

Depositing some code via the ROM monitor, then running it.
/forum/index.php?t=getfile&id=1534&private=0

Booting Conroy's customized version of the Incompatiable Timesharing System (ITS).
/forum/index.php?t=getfile&id=1535&private=0

A directory listing.
/forum/index.php?t=getfile&id=1536&private=0

Telneting in the board, logging in, checking the time, listing some files, and running ":peek", which is like Unix's top or ps. It shows me logged in as "ROBG" on the console, and "ROBG2" via the network.
/forum/index.php?t=getfile&id=1538&private=0

Rob
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Re: pdp-10 fpga [message #6637 is a reply to message #6636] Mon, 07 October 2019 18:53 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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And here's a picture of the assembled board:

/forum/index.php?t=getfile&id=1539&private=0

As a computer history enthusiast, it's been great to have an excuse to dive into the worlds of PDP-10 and the ITS operating system, which I probably would have never done otherwise.

Rob
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Re: pdp-10 fpga [message #6639 is a reply to message #6637] Tue, 08 October 2019 10:20 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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Great work Rob!
Re: pdp-10 fpga [message #6680 is a reply to message #6639] Wed, 16 October 2019 10:38 Go to previous messageGo to next message
hsnewman is currently offline  hsnewman
Messages: 4
Registered: October 2019
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Rob, will these boards run Tops-10 or 20?
Re: pdp-10 fpga [message #6681 is a reply to message #6680] Wed, 16 October 2019 11:42 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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Hi,

These operating systems would have to be ported to the board, as Conroy did for ITS. I don't know how much work that would be. Conroy wrote ITS drivers for his custom MMU, the IDE interface, Ethernet interface, and the RTC chip. You might followup in this thread on alt.sys.pdp10 where PDP10 experts could chime in on how much work would be involved if you're interested: https://groups.google.com/forum/#!topic/alt.sys.pdp10/wgEN2t DTmKg

Rob
Re: pdp-10 fpga [message #6682 is a reply to message #6681] Thu, 17 October 2019 07:00 Go to previous messageGo to next message
hsnewman is currently offline  hsnewman
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Registered: October 2019
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Do you still have any boards for sale?
Re: pdp-10 fpga [message #6684 is a reply to message #6682] Thu, 17 October 2019 15:49 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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I haven't made any boards available. This first set of boards has several errors (missing pull up resistors, power distribution errors, missing silkscreen). I'm working on another spin of the board to fix these issues and to make the board more Multicomp compatible. When I've got that done, I will make the schematics and Gerbers available and will probably have a handful of boards available.

Rob
Re: pdp-10 fpga [message #6685 is a reply to message #6684] Thu, 17 October 2019 16:05 Go to previous messageGo to next message
hsnewman is currently offline  hsnewman
Messages: 4
Registered: October 2019
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Can you put me on the list when you complete the new version?
Thanks,
Harris
Re: pdp-10 fpga [message #6686 is a reply to message #6685] Fri, 18 October 2019 14:41 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
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Sure thing.

Rob
Re: pdp-10 fpga [message #6920 is a reply to message #6686] Mon, 13 January 2020 02:57 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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Hi Rob...
I'm wondering if you have made any progress with this?
No pressure, btw.
/ Gerry
Re: pdp-10 fpga [message #6922 is a reply to message #6920] Tue, 14 January 2020 20:49 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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Hi Gerry,

Thanks for asking. I'm waiting for what I hope to be the final version of the board to arrive tomorrow. I'm expecting to get this new board assembled this weekend and have a more complete update sometime next week. Getting close.

Rob
Re: pdp-10 fpga [message #8080 is a reply to message #6922] Wed, 11 November 2020 09:14 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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I git a board for this project from Rob back in February, and between COVID related delays and various other impediments, it has taken me until now to get it done. I have 99% of the board done, with only the crystal for the RTC and the ethernet adapter remaining to fit, and they are in the mail, so I'm rapidly approaching the point of initial power-up.

Has anyone else tried this project, whether on Rob's board or their own?

I do have a couple of questions...,

1. Is there a bitstream that I can just blast onto the FPGA, or do I need to download Quartus or something to synth it from the VHDL?
2. Is there an image with Conroy's ITS I can just image to the CF card? I can see what looks like the files for ITS, but I doubt the PDP10 can understand FAT32, so I guess I need an image of a PDP10 disk, right?

Any help gratefully received.

This is the board, BTW...

https://lh3.googleusercontent.com/Uk5epz6hQkIhgvqhWY1NI9S5823B2_14Ps1BAdkkWUnndwWGnhlRHaIUt6tzPxOY4ma_4OgCfkgqP9Lx-YYm0mfg1_wKac0vcNRM8kVsVRR48kaS8n5EWu4JdJxcAAG916gpHJrFix65o6okdOYjGKDb_AGENxUz83ZMAZTCVq8LaBCL1zlWyADLijWWxtFtuisicDOsXxhH4Hnwh2Cor-ab9JTD6r2q8amYaW9PpCr_KGywhNg2dLeGrv42AZZ6s2huySUmt95qb1o75TU_cTVZgCibCAXLvTSaYbMflG4yTSWMoKqfsiZuDnH_4opVJnWigtlcbj3iuyXn1p8yvb_aD_NNZXE91LYf30j8YoJh7FKxEidaRhpR6QGcQen_cSKlIYhMl7_t5weApMIuqUJSZk3B4UEQDjOrMMVczCg0mKgzq1zH7LEjo_YSp0VY76cR-48Jxvbx9VOsnRzn7oCbBfEDlBQpM0B4N_X3dOi0hnCsB1lubMKEl7cSQ5hzutsXFaPyQFbV3qksyyd7PBKgu3hH8QIiH3Zn767Wg34ONSDuWoP0PLQyUP126naGNNfQauCzwcvskKfS5jBmCgDhj3lb8-Mb6rHTUL-jSaOTwU-pCPikwiIwj8Ihxpq1Yo9C2ICmLpY5Uv7xgmUe-VV5rtOiGYaC7tBH6R8vuyqMHjIYl0kmHm27ljyH_Q=w990-h1320-no?authuser=0
Re: pdp-10 fpga [message #8081 is a reply to message #8080] Wed, 11 November 2020 19:49 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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gerryk wrote on Wed, 11 November 2020 09:14
I git a board for this project from Rob back in February, and between COVID related delays and various other impediments, it has taken me until now to get it done. I have 99% of the board done, with only the crystal for the RTC and the ethernet adapter remaining to fit, and they are in the mail, so I'm rapidly approaching the point of initial power-up.

Has anyone else tried this project, whether on Rob's board or their own?

I do have a couple of questions...,

1. Is there a bitstream that I can just blast onto the FPGA, or do I need to download Quartus or something to synth it from the VHDL?
2. Is there an image with Conroy's ITS I can just image to the CF card? I can see what looks like the files for ITS, but I doubt the PDP10 can understand FAT32, so I guess I need an image of a PDP10 disk, right?

Any help gratefully received.

This is the board, BTW...

Hi Gerry,

You're the only person I sent a board to. I've since reworked to the board to use a Spartan-6 FPGA board. The Spartan-6 is not only larger, allowing for more system possibilities, it is cheaper too. I've almost got the revised board ready for anyone who might be interested.

Anyway, I'll continue to support your use of the Spartan-3E version. Answers to your questions:

1. I've attached a dump of the serial ROM used with the board. This binary file contains the FPGA bitstream and the 1K-word PDP10/X ROM image. Just burn this to the W25Q32JV and you should boot into the ROM monitor immediately on power-up.

2. The archive hosted by this site at http://www.retrobrewcomputers.org/fpga-pdp10-archive/v3arch. zip contains the necessary disk image at v3arch/disk/sim10x.disk. Write that to your Compact Flash card.

Let me know if you have more questions...

Rob
Re: pdp-10 fpga [message #8082 is a reply to message #8081] Thu, 12 November 2020 11:20 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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Awesome! Many thanks. Will give it a try over the next day or two.
Re: pdp-10 fpga [message #8093 is a reply to message #8082] Mon, 16 November 2020 13:40 Go to previous messageGo to next message
hsnewman is currently offline  hsnewman
Messages: 4
Registered: October 2019
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Rob,
When will you update the files to be for the Sparten 6? Also, does the pdp10x have the ability to multiboot under multicomp? Finally, are you in Austin, I'm in Cedar Park...
Re: pdp-10 fpga [message #8094 is a reply to message #8093] Mon, 16 November 2020 21:37 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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Hi Harris,

I hope to update the files for the Spartan-6 version in the next couple of weeks. It won't be on the Wiki, probably GitHub instead, as I can't reset my wiki password with the forum email not working. The stuff I have on my builderpage is for the Spartan-3 version, frozen in time.

I'm not sure exactly what you mean by "ability to multiboot," but the board can run both Multicomp and PDP10/X, though switching between them is a manual process of using the Xilinx ISE/iMpact tool to program the FPGA or serial ROM each time you want to switch. And as a bonus Smile because the QMTECH FPGA board I'm using has SDRAM, the system will run Will Sowerbutt's socZ80, which Alan Cox once referred to as one of the fastest non-software-emulated Z80 system he's used.

And yep, I'm in Austin, on the southwest side. Howdy neighbor.

-- Rob

/forum/index.php?t=getfile&id=1924&private=0
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Re: pdp-10 fpga [message #8096 is a reply to message #8094] Sat, 21 November 2020 22:10 Go to previous messageGo to next message
djmartins is currently offline  djmartins
Messages: 40
Registered: February 2018
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How about porting it to the MiSTer FPGA system?
Already a few retro machines on MiSTer including a PDP-1 and
would love to see more DEC machines on it.
Re: pdp-10 fpga [message #8413 is a reply to message #8081] Fri, 26 March 2021 03:09 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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robg wrote on Wed, 11 November 2020 19:49

1. I've attached a dump of the serial ROM used with the board. This binary file contains the FPGA bitstream and the 1K-word PDP10/X ROM image. Just burn this to the W25Q32JV and you should boot into the ROM monitor immediately on power-up.
Hi Rob

Got a little sidetracked over the last few months, but finally got round to trying this. I hvae an SPI EPROM flashed with the attached image (and verified by reading off and diffing against the original binary). The FPGA starts up with the default LED flashing image, but that's as far as it goes.
If I connect a serial terminal to the TTY, I just get a series of NULLs.

I have traced the SPI lines from the EPROM to the FPGA headers, and all seems fine.

I guess I am missing something obvious but can't think what it might be.
Re: pdp-10 fpga [message #8416 is a reply to message #8413] Fri, 26 March 2021 21:27 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
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gerryk wrote on Fri, 26 March 2021 03:09
robg wrote on Wed, 11 November 2020 19:49

1. I've attached a dump of the serial ROM used with the board. This binary file contains the FPGA bitstream and the 1K-word PDP10/X ROM image. Just burn this to the W25Q32JV and you should boot into the ROM monitor immediately on power-up.
Hi Rob

Got a little sidetracked over the last few months, but finally got round to trying this. I hvae an SPI EPROM flashed with the attached image (and verified by reading off and diffing against the original binary). The FPGA starts up with the default LED flashing image, but that's as far as it goes.
If I connect a serial terminal to the TTY, I just get a series of NULLs.

I have traced the SPI lines from the EPROM to the FPGA headers, and all seems fine.

I guess I am missing something obvious but can't think what it might be.
Hi Gerry,

In that November message, I incorrectly suggested that the Spartan-3 FPGA configuration is loaded from the SPI ROM on the system board, but that's not right. On the Spartan-3 version you have, the SPI ROM on the system board provides the PDP10/X boot code, while there's a separate ROM on the FPGA daughterboard that provides the FPGA bitstream. So you''ll need to use the Xilinx ISE tools to program the FPGA. I'll need to send you a bitstream. (On the Spartan-6 version, it is the case that there's one ROM that stores the FPGA config and the PDP10/X boot code.)

-- Rob

[Updated on: Sat, 27 March 2021 06:42]

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Re: pdp-10 fpga [message #8417 is a reply to message #8416] Sat, 27 March 2021 03:59 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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Ah right... that makes sense.
I do have an Xilinx JTAG to flash the ROM in the FPGA, so no problems there.
Thanks
Gerry
Re: pdp-10 fpga [message #8418 is a reply to message #8417] Sat, 27 March 2021 09:36 Go to previous messageGo to next message
robg is currently offline  robg
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Registered: October 2017
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Hi Gerry,

Here's the bitstream file you need to load into the FPGA's config ROM (xcf04s) via Xilinx's iMPACT tool.

-- Rob
  • Attachment: kx.mcs
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Re: pdp-10 fpga [message #8422 is a reply to message #8418] Mon, 29 March 2021 06:29 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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Thanks Rob...
That worked... up to a point. I have an image on the FPGA EPROM that boots to a different LED pattern L1, L2 light up along with Power and Flag. But that's as far is it goes.
Would you have any suggestions?
/ Gerry

/forum/index.php?t=getfile&id=2042&private=0
Re: pdp-10 fpga [message #8424 is a reply to message #8422] Mon, 29 March 2021 09:51 Go to previous messageGo to next message
gerryk is currently offline  gerryk
Messages: 16
Registered: February 2017
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Incidentally... just came across this: https://github.com/aap/fpdpga
Both PDP6 and PDP10 implementations. Not quite as advanced as your/Conroy's implementation in that no mass storage yet, but still interesting.
Re: pdp-10 fpga [message #8425 is a reply to message #8424] Mon, 29 March 2021 11:02 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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I haven't looked at that PDP10 FPGA. There are several floating around on the internet.

BTW, I sent you a couple of private messages. I suggest we move the debug of your board to email for convenience.

-- Rob
Re: pdp-10 fpga [message #8426 is a reply to message #5326] Mon, 29 March 2021 22:03 Go to previous messageGo to next message
robg is currently offline  robg
Messages: 43
Registered: October 2017
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Ok, let's simplify things a bit. I've attached 'kx_bram.bit' which is the PDP-10/X bitstream that doesn't use the config ROM nor the SPI ROM. The Xilinx tool will write this via JTAG to the FPGA's SRAM. Note, in this mode, the FPGA will forget the bitstream when the power is off.

After you program this into the FPGA, you should see something on the serial port (set to 9600 baud 8N1). Hopefully you'll see

ROM10X.85
?RTC ERR
.

Before doing this, you might find it helpful to reprogram the FPGA config ROM with the default LED demo bitsteam, which I've also attached. I find this useful to easily tell the difference between a default bitstream and a programmed bitstream.

If load 'kx_bram.bit' works, then you can load 'kx_bram.mcs' also attached, into the FPGA config ROM. Program the ROM, turn off the board, then turn it back on. You should see the same serial port output. If that works, that will be the permanent bitstream for the board. The SPI ROM will no longer be used at all.

Let me know how it goes...

-- Rob



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[Updated on: Mon, 29 March 2021 22:05]

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Re: pdp-10 fpga [message #8448 is a reply to message #8426] Sat, 10 April 2021 15:03 Go to previous message
djmartins is currently offline  djmartins
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https://github.com/MiSTer-devel/Main_MiSTer/wiki

Check this system out, it is ripe for more DEC retro cores.
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