Philips P800 Series P850 P856

I recently found this computer series.
There is a site with emulators

And I also found this Dutch forum with photos of parts in color, nice panel.

https://www.circuitsonline.net/forum/view/135384/1

Typical 70s. Doesn’t even look like a computer. (from cpushack)

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That is actually my desk, and my P854…
Hate to say it, but I threw away some 7-8 Philips P856 machines with core memory and blinkenlights, some 15 years ago, as nobody was interested…

The machine was better than a PDP11, but lacked software suppport and marketing. Philips did make a microprocessor variant, the Signetics spc16/10, which must be the most unknown microprocessor ever…Still looking for a datasheet…

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You could always port Fuzix to it if you’ve got enough RAM and the MMU option :wink:

The emulator is scary, that’s not what I thought perl was designed for

There is a free e-book about the Philips P800 series in general and the Philips PTS6000 in particular. It can be found here: https://www.researchgate.net/publication/377777427_The_Rise_and_Fall_of_Philips_Data_Systems

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Thanks Arne - I see you are a co-author. Glad you were able to make your work available for free.

Hi Arne,

do you happen to have run across a datasheet for the SPC16 ? I am currently designing a singleboard computer with the SPC16/10. A fullk datasheet would be very welcome…

No, sorry, I did not. The closest I have seen is this thesis from Eindhoven that I am sure you have also come across: https://pure.tue.nl/ws/files/4286409/8105760.pdf. It has some schematics at the end from which you can guess a few things, but not close to a real datasheet.

I worked with software down to the operating system (which was a bit complicated due to the firmware/software distinction/banking of the primary memory), but never with hardware

I had no idea there was active development using the SPC-16, fun to know. Our PTS 6911 workstation controller also had to use the interrupt and memory handler chips in the chipset, in order to be as compatible as possible with all the other machines in the PTS range.

Good luck with your build!

Best,

Arne

This was a thousand-plus-hours not-for-profit hobby project for many years. Happy if you can spread the word around to those interested in European computer history.

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I must be crazy to go ahead and design a SBC for a CPU for which there doesn’t seem to be a datasheet surviving…But I am crazy that way…

And know the realisation of the above idea :

Reset behavior is as expected, as yet no software has been written so that is the next major step.
PCB’s are available if you want to join in !

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This looks interesting… what kind of I/O and memory arrangement are you planning?

Looks like there are a few processors available on eBay.

Where did you get the led bar? It 7 segment or 14 segment?

The SPC16/10 has a 32Kx16 “software” memory, and additionaly a 32Kx16 “firmware” memory, all on the same bus. With today’s memory it is easy to provide a full 32Kx16 software memory ( for user programs ) As Firmware memory ( OS / system use ) I provide for 8Kx16 RAM and 16Kx16 Eprom.
I/O are 2 RS232 channels, IDE disk. optionally a RTC, par. in & out and a 8 character LED display.
Addressdecoding per GAL, such that easy corrections are possible.

The 7 segment display on the Kicad 3D ouput is only because they share the same footprint.

I’ll mention it here just in case someone else is looking for the info :
The Philips P853 uses the CP1A processor board, which itself uses the SPC16/10 microprocessor.
Though the schematic designates the microprocessor used as “XSC2752” it is in fact a SPC16/10.
Also the buscontroller SPC16/12 and interrupt encoder SPC16/11 are used in this design.

Good to see this project is still in progress.

There is still hope that my ROM-emulator can be adapted to 16 bits (or 2 times 8 bits) before the project is ready for reproduction. The current 8-bits version of the emulator is very useful for firmware development.
Greetings,
Fred Jan

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As always, it took longer than expected. But the above board is now up and running, a simple assembler has been written. A first program that display the SPC16’s registers via the RS232 channel has been demonstrated to work.
I would still like to see a datasheet though…

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How do you plan to bootstrap?

Not sure what you mean…It just starts up like any regular microprocessor, i.e. by reading a starting adddress from the ROM.
Adapting an existing OS will have to wait until I have a better software monitor.