Original Derby Specification
I've scanned an original Derby specification, from Nov 1985, and uploaded it to my site - I think I acquired it during my fleeting association with Mikrogen.
I don't know if this exists on WOS yet, but is a historic document. Feel free to upload it.
http://www.zxdesign.info/docs/derbySpec.pdf
I did intend to OCR and create a smaller PDF, but it was too tedious.
I don't know if this exists on WOS yet, but is a historic document. Feel free to upload it.
http://www.zxdesign.info/docs/derbySpec.pdf
I did intend to OCR and create a smaller PDF, but it was too tedious.
Post edited by csmith on
Comments
The interface 1 documents in the WoS archive are a good example of OCR rendering the document more or less unusable.
Hi Chris,
What was Derby? Looks interesting... do tell.
Paddy
Derby was the "codename" for the ZX Spectrum 128K.
I cannot confirm the dates in this link: http://en.wikipedia.org/wiki/ZX_Spectrum#ZX_Spectrum_128
So this document pre-dates the release of the machine, and was made available to help software companies get a head start in developing titles for the machine.
It's interesting to note that even at this stage, contented memory as documented (pages 4-7) doesn't match what was implemented in hardware (odd numbered pages).
Jon.
The Z80 clock signal is brought out to the edge connector (Whoops). :lol:
I didn't understand that bit, why is it whoops? The 48k brought !CK to the edge connector too...
Ah, interesting. You are a fountain of all things Speccy sir! ;-)
Paddy
Because on page 13 of the document it says that it isn't connected...they obviously changed their minds between pages 13 and 14 :lol:
Nx
I doubt that it was specifically tested for. Exiting titles would have worked fine so would be difficult to spot.
But this is the issue yes? That the Amstrad machines contend the pages from the Derby spec rather than what the actual 128k hardware did?
I just want to make sure I understand it right so I'm not perpetuating myths further down the road. :smile:
Nice find, but what happened to pages 4,5,6 and 7? :-P
And it's true. In another post of wos, we spoke about missing CLK signal on spectrum +128K egde connector.
I remember open my spanish spectrum +128K ( with investronica 2.1 PCB ) and see that CKL pin of the egde connector doesn't have any track. In other words, you can't take the CLK signal from a spanish spectrum +128K.
About "Derby"
As you probably know, Spectrum +128 K was developed by sinclair and spanish company "INVESTRONICA". The first presentation of spectrum +128K was in spain in 1985. The spanish magazine MICROHOBBY put an article about the presentation of this spectrum model.
In this magazine, the people of INVESTRONICA said that all computer companies were competing to get new models like in a motorcycle race. This is why the first spanish +128K had eproms with the word "DERBY". (DERBY was a spanish motorcycle company that won many Championships in 50cc, 80cc, 125 cc )
You can see this "DERBY" eprom in this RARE spanish +128K with INVESTRONICA 2.0 PCB
http://hardware.speccy.org/imagenes/ordenadores/spectrum128k-SP2.jpg
Bye
Jos? Leandro
Err, dunno. I thought they were all there. I'll check the paper copy tonight, perhaps I missed scanned them - though I just dropped the doc onto our funky copier in work and it did all the work. If I don't have the paper pages, then I never did - this had been in my loft since the late 80's.
I think he was referring to contended pages...
There was an error on the Investronica 128K PCB, they forgot to wire the CLK signal at the edge connector to the CPU. Every so often one of the Spanish Spectranet early adopters try it out on a Spanish 128K and find it doesn't work, the Spectranet needs the CLK signal...
Maybe... Maybe... But by sheer coincidence paper pages 4-7 are missing too :-(
Heheh, yes I did mean the printed pages! :lol: