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Recreating the Ferguson Big Board
- Thread starter hideehoo
- Start date
Nice work!
gekaufman
Experienced Member
Amazing job duplicating this board, both electrically and visually. Thanks for letting me tag along!
Just waiting for a few oddball parts (like the darn 7445 TTL) to arrive to finish up, but seeing System Monitor 3.3 on the screen was very rewarding!
- Gary
Just waiting for a few oddball parts (like the darn 7445 TTL) to arrive to finish up, but seeing System Monitor 3.3 on the screen was very rewarding!
- Gary
hideehoo
Experienced Member
It was a pleasure working with someone who had first hand knowledge. Now to capture everything I've learned on Github (setup, diagnosis, scope traces, etc.) for the next person. Also still need to figure out the best way to test the CTC and extra PIO functions before I spin a new version of the board, but going to spend some time hopefully getting the original built board running before VCFMW. My son posted some pics of it when we first got it in this thread, https://forum.vcfed.org/index.php?threads/ferguson-big-board.67999/ Just got done giving it a bath and cleaning off the big pile of snake shit that was in the middle of the board.
Also moved the repro board upstairs and hooked it up to an actual monochrome CRT monitor. 1000x better picture than what the Dell LCD was doing with the composite output.
hideehoo
Experienced Member
gekaufman
Experienced Member
Well, if you need another challenge, it would be fun to duplicate the DD board
I recall that there is code for the CTC in some of MicroCornucopia's stuff.
I recall that there is code for the CTC in some of MicroCornucopia's stuff.
hideehoo
Experienced Member
Well, if you need another challenge, it would be fun to duplicate the DD board
I recall that there is code for the CTC in some of MicroCornucopia's stuff.
Hmmm, no sure on the feasibility of this one.
Most of the chip markings are faded and now unreadable, it has a bipolar PROM on it (the Harris M3-7603-5), and even if we could duplicate the hardware, not sure the correct software and/or patches are still around to make it work unless someone here recognizes the model. Although maybe it's an early version of the SWP card described on Enrico's site, https://www.vintagesbc.it/vintage-c.../ferguson-big-board-i/schede-figlie-e-add-on/ so there could be hope?
I take it that's a different display than the early photos with the Tetris game? The resolution looks very nice here, compared to those earlier photos. Was that because those were flat panels and the conversion from composite to digital? Or do you think the resolution was en route to be improved on the flat panel displays?
hideehoo
Experienced Member
Ya, early photos were on a Dell LCD on the workbench, looked pretty bad (and worse in the photos than in person) but that is often the case with retro computers in my experience. Probably could have been improved with some settings tweaks on the monitor, but was only concerned about functionality. The latter one is on a vintage monochrome CRT with the brightness and contrast properly adjusted. Looks really good and like other computers of that era.
gekaufman
Experienced Member
Sure looks like the SWP board. If so, it should be supported by the "SmartROM" by MICROCode Consulting, https://www.microcodeconsulting.com/z80/smartrom.htm
I can copy/duplicate the PROM and one of those cute TTL testers should identify the IC's (or confirm they are the same as Enrico's pic). I about 10 spare FD1791's here too which should be 8876A compatible.
Finding bios source might be a bit tougher!
I can copy/duplicate the PROM and one of those cute TTL testers should identify the IC's (or confirm they are the same as Enrico's pic). I about 10 spare FD1791's here too which should be 8876A compatible.
Finding bios source might be a bit tougher!
gekaufman
Experienced Member
Well, bios for SWP appears to be here...
gekaufman
Experienced Member
hideehoo
Experienced Member
I'll DM you regarding getting a board, but being in Holland shipping and customs could be expensive.
Looks like @P9P2P8 has been able to create new PAL's for the BB2 and got his largely working. https://forum.vcfed.org/index.php?t...bringing-up-the-bigboard-ii-ferguson.1240054/ Is it a coincidence you are both in the Netherlands?
gekaufman
Experienced Member
Video and Keyboard both running nicely now. I was getting some jitter (a common BB1 problem) and changing U11 to a 74F04 seemed to improve it.
The board also works nicely with XMON4 (2716x2) which adds a few features (but removes the memory test).
Printed up your RT-50B case, very nice.
Getting ready to hook up FlashFloppy once my 7445 arrives (or I may just steal one from another system). What disk image(s) did you use?
Thanks!
The board also works nicely with XMON4 (2716x2) which adds a few features (but removes the memory test).
Printed up your RT-50B case, very nice.
Getting ready to hook up FlashFloppy once my 7445 arrives (or I may just steal one from another system). What disk image(s) did you use?
Thanks!
hideehoo
Experienced Member
I converted the standard Big Board BB1 through BB4 IMD files to IMG format and then created a custom Flashfloppy format definition for them in IMG.CFG. All the files are at https://github.com/djtersteegc/Ferguson-Big-Board-Reproduction/tree/main/flashfloppy, just copy them to a USB stick and stick it in your FlashFloppy. I also just added a GAMES.img disk that my son created last weekend by transferring via PIP of some of the classic CP/M games.
DeltaDon
Veteran Member
Nice work! I like to see new boards for old systems recreated. I never had a BB back then, but often wanted to get one. Never had the cash. Now days I do have an Ampro Little Board (early version - no SCSI port) with twin 5.25 Quad density drives all mounted in a dual SCSI drive case with power supply. So I guess I guess that's close.
hideehoo
Experienced Member
Swapped all the vintage chips in my reproduction with news/used ones from UTSource (still working yay). Took the cleaned up original board, replaced the zener at VR1 that was dropping -12V to -1.76V instead of -5V, and then reinstalled all it's original chips. It has the 4MHz mod that uses the 16 MHz main crystal described on page 3 or Micro Cornucopia #3. Fired it up and while I have some screen corruption, it is responding to keyboard input and I get a clean PFM 3.3 prompt on the serial ouput, so it is running! Little more troubleshooting tomorrow and I should be able to display them both at VCFMW.
