Category Archives: Olivetti CP486

Olivetti CP486

The Olivetti CP486 was “the other” machine on the market which provided an 80486 and an 80860 on the same mainboard. The same board was used in Olivetti machines called LSX-5010 (25MHz) or LSX-5020(33MHz).
Like the Hauppauge 4860, it was an EISA bus system too, had no 2nd level cache but an extra socket for a Weitek 4167 FPU. Again very similar is the use of an huge array of PALs and GALs… and huge is the keyword for its size:  40,5 cm x 34 cm (16″ x 13.4″)!

CP486_total

My CP486 which I’m showing here seemed to have been through very though conditions. It was quite dirty and is of course not working :-/ Mainly due to a missing PAL, I guess (shown in the following picture).
So here’s the lower part of the board (90° tilted for better reading):

CP486_left

At the top the i486, in this case an DX2/50 I had lying around – nicely fitting the 25MHz oscillator to the right of it. At the edge of the photo you can see a bit of another socket. That’s where the optional Weitek FPU would have go (See the picture of the total view).
Next you’ll spot the many PALs around it. And a wild mixture it is! All PALs/GALs on the board are from different manufacturers, years and kinds. Some still featuring labels, most of them peeling off. According to the only documentation I was able to find, “in field” upgrades seemed to happen quite often. The little red arrow indicates the missing PAL at “U82” I talked about before. It should be a 16R4 containing the snoop-control, a vital part of the memory management. Without it, the board is pretty much brain-dead 🙁
Next are 8 slots for PS/2 SIMMs… depending on the BIOS version up to 64MB RAM were usable.

In the low left corner is what made this board special: The i860 socket. The 3 PALs above it are his address decoders… nothing is known about how the two processors shared the RAM.

Which leads us to the other half of the board:

CP486_right

This part is mainly chip-set stuff. At the top left there are the Intel 82358 EBC and 82537 ISP (See my Knowledge-Base article for more info) ICs.
The rest of the action is squeezing into the lower right corner: On top the WD16C552 Serial and Parallel Port Controller. The other two bigger PLCC ICs are EP1800 CPLDs supposedly working as I/O controllers. To their right is a 8742AH handling the PS/2 keyboard and mouse.
Below that there’s the inevitable DALLAS clockchip, a 64kbit EEPROM (probably EISA config) and a 1Mbit 28F010 Flash EPROM for the BIOS. Pretty modern stuff actually.
Naturally I read out the BIOS… it’s completely Olivetti propriety as they always did back in those days (Download available at the end of this page).
Last but not least, the power connector. Again, propriety but I do have the original power supply. Nice big paper weight.

The EVC-1

Like the Hauppauge 4860 (again), the CP486 also offered a special Graphics Card which enabled the i860 to directly write into its video memory, so it could be used as an accelerator.
While Hauppauge went the way of offering a special dedicated slot, Olivetti designed a special EISA Video Card… well, the EVC-1.

CP486_EVC

While it features a standard EISA slot connector, it does not work in other EISA systems (You get the BIOS boot messages but it then hangs with wire-do chars displayed).

It’s core is a Chips & Technologies 82C452, a mediocre VGA chip.  Olivetti attached this DRAM VGA controller to 1MB dual-ported DRAM… This totally makes sense because the 82C452 can act as a simple VGA controller while the i860 will als be able to write to the screen (via EISA DMA) for example doing the heavy lifting graphics stuff. The idea is the same as Hauppauges Framebuffer but enhanced with a VGA controller.
That said, IMHO 1MB video memory is a bit less for such a professional approach.

Conclusion

So, here‘s the CP486 PDF-document I was able to find in the WWW including my BIOS dump.
If you happen to own a CP486/LSX50x0 I would be happy to hear from you!

Final anecdote: I’m not sure this guy (German forum, Google-Translation here) knew what he was doing when scavenging a complete, fine running LSX-5020 for a boring case-modding stunt. In a few years he will kick his ass for killing a one-of-a-kind machine for a boring mass-market PC.
That’s the same sin many Americans did to their vintage Ferraris when they replaced the somewhat complicated original engine with an off the shelf Ford V8 to make it reliable… and reduced its value to 10%. Sin! Sin I said!

Olivetti LSX 5010

Years ago I got that broken Olivetti CP486 board (the predecessor of the LSX 5010 and 5020 family) – one of the two ever made i486/i860 combo Mainboards (the other one was the 4860 by Hauppauge). Well because it was broken, missing important parts and I felt like I’m the only one on the planet having such system I dumped it.

There’s life out there!

Now I learned there are at least two LSX 5010 owners left on this planet and one of them contacted me, primarily asking for an i860… well, long story short:
His LSX 5010 was broken, too, but complete! We agreed on a deal: I try to fix it (plus an i860) and he’ll give me a system out of his collection.

Some days later I had everything I’d call a good-to-go system:

The grey box with an LCD display is the “console”, giving you POST information, a speaker and some buttons. Next to it the huge power-supply and in the slots you can spot the EVC-1 graphics card an my trusty ISA/PCI POST card…

Let there be light

Booting the system just the console showed a “CMOS Periodic Int Error“. Doing a warm-boot it replaced by a „Base 128k Ram Error“.
Additionally it behaved somehow flaky, booting  into different states every now and then:

These three Errors were solvable:

  • Flaky behavior: Replacing all caps – this always helps. Believe me. The system booted into a reproducible state after this.
  • CMOS error: The dreaded DALLAS CMOS clock-chip… we all know the drill. Its battery is empty and EISA systems heavily rely on a working CMOS storage. So it got an external battery surgery.
  • RAM error: That was a bit tricky. The LSX’es need parity RAM. One SIMM per bank. Max. mem is 16MB – I only have 16MB+ SIMMs. So I had to get small parity PS/2 SIMMs. 2x4MB did it.

Booting the system now, the console greeted me with

  • „Console Passed“
  • „P.O.D. Running“ (That’s the Power On Diagnostic)

…and then „Non-Maskable Int. Error“. Dammit! This can have many reasons, most of the time it’s RAM (parity). But in my case, it’s been different…

That was a fun one (actually two):
The trace to the i486 processor NMI-pin (B15) was scratched and needed repairs. But it still kept throwing that error. Why-oh-why?!?! After a whole day of digging I had a severe facepalm-moment:

The owner replaced the CPU by an 80486SX because he was under the assumption the LSX 5010 was an SX system. But it wasn’t. It’s a 80486DX @ 25Mhz system (while the 5020 is 33MHz).
And while everybody is claiming the SX is just a DX minus FPU… it is not a 100% drop-in replacement!
While the DX’es have their NMI-pin at B15 the SXes have it located at A15 (where DXes have IGNEE) and B15 is not-connected. Doh! (Checkout the pinout here)

So replacing the SX by one of my 486DX  we finally got a full boot! Tadaa:

Those stripes came from the EVC-1, which definitely also had its problems. So checking its board with my microscope I came about this:

Uhhh…. a cracked diode (D14) connected to address-line A0 to the video RAM. That explains the lines quite well.
When the new DA5 (BAR43S) diodes arrived I replaced the broken one, fired up the LSX 5010:
Looking good, booting into the EISA CMOS setup and while editing the config I could watch the picture disintegrating by every keystroke. More and more garbage was displayed, columns disappearing until it was all black.
The EVC-1 literally died in action in front of my eyes 🙁

I’m not sure what happened here. The fixed address-line can’t be responsible for this. All ICs still get their clean 5 volts. I suspect that one or more of the many old PALs (some of them even bipolar) died…

Ride on…

Anyhow, plugging in my ET4000 workhorse I was able to resume the setup. EISA systems always need a setup tool to tell them all the features of their Mainboard as well as the cards being installed. Luckily the owner had the basic tools at hand… you’re screwed without them.
So this is the one for the LSX booting:

After that’s been done I ran the diagnostic tool – in German just for the fun of it (You can spot all those “OKs”, right?)

But wait a second! Isn’t there something missing?
You’re right… here you go:

The mighty i860 RISC processor… and it is detected just fine: “Pass” 🙂

But does it work, too?

Yes it does! Hooray… mission accomplished!

Downloads

As usual, here are the dumps of the BIOS, Config EPROM and CMOS.
Additionally, you’ll find the floppy images of the config- and diagnostic tools in this archive.

Conclusion

The LSX 5010 is very much like the Hauppauge 4860 a fragile system to work with.
If the unusual configuration of EISA systems weren’t enough, the use of the many, many, many proprietary ICs (i.e. GALs and PALs) make them prone to aging and hard to fix.
They were bespoke designs, limited in their compatibility – Olivetti lists about 30 cards (VGA, SCSI, most of them multi-RS232) officially working – and most importantly need specific parts like the console and software.
Without the proper EISA config tool you always get at least error messages. Without drivers for the i860 you will not be able to use that and it’s just a heating-element inside your computers case.

Those (server) systems were meant to run as-is. Pretty much like a SUN, HP or SGI server of the same period. You can pick from like 2-3 devices to add and that’s pretty much it. They were not designed as an average PeeCee running Doom.