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Logo Nuova Elettronica
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The Z80NE is a project of the Italian magazine of electronic "Nuova Elettronica" and it was published in 1979.

Nuova Elettronica was founded in 1969 by the hands of the brilliant and unfortunately passed away Giuseppe Montuschi and closed its doors in February of this year (2014) to my great regret.

 
Logo Nuova Elettronica
Magazine Logo

Despite the long period of activity and the large number of successful projects and related kit products by Nuova Elettronica, still today, talking about the magazine the first thing that is remembered is just the microcomputer Z80NE.

Premise that i will not go there too deep in describing machine details. To know all about the Z80NE, there is a very complete site of my friend Roberto Bazzano "The home of Z80NE" to which you can refer for any further information.

 

It was the year 1979...

However, I can not describe this project if not making a small digression on the period in which this kit has seen the light, because I can not ignore the great impact that this computer has had on my life.

The times were not yet become frantic as they are today, and there was time to think about things. Electronics had become "fashionable", so to speak, when his presence started to get into any everyday object with effects presented as miraculous.

And they were...

It was in progress a true cultural phenomenon, generated by the great pressure that the market was doing with the arrival of the "silicon".

Even movies and books of the moment heavily were affected by this new fascinating presence.

A charm that certainly was having great influence on many people, radio amateurs and electronics geeks, always armed with tin and solder iron, intent to mess up everything happen to throw, from transistor radios to the lights of the stairs, the timer for the camera flash or the electrical systems of their car. And they were numerous and in full operation at the time, as evidenced by the presence in each kiosk of a large amount of magazines devoted to the subject and by the opening of shops selling electronics at every street corner.

I was not an exception. At the second year of the high school (that is five years long in Italy) it was already clear to me that electronics would be my future. After high school i would have go to the degree course in electronics engineering.

Or so i thought ...

In this context, digital was really the last frontier. Computers simply does not exist. Not in the sense that we are used today to be clear.

There were computers, yes, but as a mysterious presence, of which there was much talk, "A job for the future? Become a programmer!". Yes, but how?

The massive invasion of personal computers like the ZX80/81, the Commodore or the Apple II and many others, was still some time away. The same Z80 processor in 1979 was a new thing, the marketing of which was begun only in July of 1976.

Yes, if you wish, you could buy a computer, such as those based on the S-100 bus, but the spread of these systems despite the publicity, was quite poor, especially in Italy, not to mention the prohibitive price, I'd say science fiction, which they had for a kid at the beginning of high school.

In this framework, just before the boom of Apple, Commodore and Sinclair, and then the cataclysm made by IBM with its "Personal",  there was Nuova Elettronica at the time my favorite reading.

From what has been published, you could guess that something was brewing, with the increase number of articles and kits containing ROM, EPROM and the like. Not that digital was absent from the projects of the magazine, the contrary, even though you could see the emergence of new kind of components.

Nuova Elettronica has always had a very unique approach in the field of specialized press. In the first place every published project was based on a corresponding kit, of which the magazine punctually provided printed circuit board and components in a classic blue-black "blister".

But what always really characterized its contents was the explanation precise, didactic, of the circuits operation  both practical and theoretical, using a language so simple that it was impossible not to understand the principles.

Finally on the number 68 of the magazine appears the project of this computer kit.

original-kit
Z80NE aka "Microcomputer Z80" picture from issue 69
 
copertina 68
Issue 68 cover

It is a system based on a Z80 cpu at 2 MHz and realized on dedicated cards connected via a proprietary bus. Initially were proposed: the CPU board complete with 1Kb of monitor on EPROM and 1Kb of ram, a 7 slot BUS board, an hexadecimal keyboard with eight seven-segment display, and the interface card for the hexadecimal keyboard, followed on the next issue of the magazine (69) by a power supply that enables its effective functioning.

Evidently a very didactical initial approach.

But for me more than enough. Is love at first sight.

Immediately began the nights spent experimenting on the hexadecimal keyboard and, in parallel, related fits of anger when things "inexplicably" do not work. But every challenge overcome led to something more complicated, like a drug, inexorably programming and computer science became a part of myself.

Each proposed addition later, memory expansion, interfaces for cassettes and floppies, video interface cards and more (not to tell you the excitement of seeing charachters appear on the screen pressing on the keyboard buttons) does nothing but increase my infatuation for "computers" .

Now it seems only rhetoric, but later and only because of those two initial stupid cards, i gave up engineering degree to devote myself exclusively to programming my beloved computers, thing, that i'm still doing.

Infact today i'm developing the project in this picture:

sts
STS, Supervision and Tracing System running at Telecom Sparkle's facility.
Acilia (RM) - 2010

 

but, if it were not for the Z80 by Nuova Elettronica, it was never possible.

imgp0123-or
Z80NE running at home. (Picture by Pino Giaquinto)

 

Microcomputer Z80 by Nuova Elettronica

 

As already said the system consists of dedicated boards. Each card performs a specific function and all the main boards are connected on a propietary bus.
As i found out later, the original design of the system was effectively developed by a company called Micro Design of Genoa and not by Nuova Elettronica.
The orientation however, is to provide an educational system as evidenced by the basic system that consists of the CPU board and an hexadecimal keyboard.
The magazine, however, has introduced later a comprehensive set of additional hardware to allow the construction of a complete system of a level comparable to systems like S-100s or TRS-80 just for an example.
The kits provided by Nuova Elettronica were presented fairly quickly at the beginning and then slow down over time.
The whole system is developed, however, covering a period of considerably long time from 1979 to 1985, which is much greater in life expectancy then today's PC.
The decision to break up the presentation and furniture of the Z80NE hardware, worked well for both the magazine, interested in selling kits and so to maintains high the interest in his system, both for the users who can spread over time the costs (quite remarkable at the end) of buying the whole system and, at the same time, having the time to "assimilate" what the magazine continues to offer in terms of didactic information a kit after another.

The board design is sophisticated and robust, with low component density so to put even the less "technically savvy" people able to mount the components without errors (well... almost).
As to be noticed, not all the hardware presented can be used simultaneously, for example, there are two video interfaces, a low resolution and a hi-res which are mutually incompatible, as well as various memory cards that can only be used in certain configurations to obtain a maximum of up to 56K of RAM which is the limit for our computer. This is because the upper 4kbytes are used by the monitor and lower 4k of RAM (a single kbyte used actually) from E000H to EFFFH is reserved for the lo-res video card.
Another interesting case is the system monitor originally present on the CPU board, which maps 1kb of EPROM at address 8000H, thus blocking any expansion above 32k, chip that infact was removed almost immediately, and placed on the floppy interface card (mapped at F000H).

This apparent schizophrenic design is explained, over the time, with the intent to have a system that users can set up accordingly to their needs and interests.
Even if, i'm willing to bet that the most of them have brought their Z80NE to its maximum potential.
Many of these limitations can easily be overcome with small interventions, as we'll see later.

This is the list of Z80NE kits produced by Nuova Elettronica:

Issue

Kit

Item

68

LX381

7-Slot BUS (there was also LX381/B a 10-Slot BUS board)

68

LX382

CPU Board

68

LX383

Interface for hexadecimal keyboard and display

69

LX380

Main Power Supply

70

LX385

Cassette interface

70

LX386

8 KBytes static memory expansion

72

LX387

Alphanumeric keyboard (and LX387/B with numeric keypad connector)

72

-

Thermal printer (every Centronics parallel printer can be used)

73

LX389

Printer interface & parallel port

73

LX388

Video interface (low resolution MC6847 based)

73

-

Monitor 12" complete with terminal case

75

LX390

Floppy disk interface (FM - Single density, on the same issue also Tandon TM-100 5" floppy drive )

75

LX394/5

EPROM programmer (and also UV Eprom eraser)

76

LX391

Floppy drive power supply

76

LX391

32 KBytes dynamic memory expansion

80

LX599

12" Video monitor

84-85

LX529

Video graphics interface (high resolution SY6545A-1 based)

84-85

LX530

Beeper daughter board for LX529

89

LX547

50Hz interrupt card

89

LX549

Numeric keypad (to be added to LX387/B)

96

LX548

16 KBytes BASIC interpreter on EPROM

101-102

LX683

SASI Hard disk interface

103

LX710

Autorepeat for LX387

 

 

The system BUS is parallel, consisting of 48 lines divided on two single-in-line connectors of 24 pins each.
The connector "A" drives power (-12V, + 12V, + 5V) and all control signals of Z80 cpu including IEI, IEO pins that should established a daisy-chain interrupt priority between the cards according to the position of insertion, feature never used by Nuova Elettronica, while the connector "B" was dedicated to the address and data lines.

Normally, the power supply and the boards were enclosed in a 5U rack mount black case. This all-black style led me to give to my system the nickname of Z80Darkstar, for which you'll find references in the next articles.

For all details about every board and also original schematics and magazine articles, please, look here: http://www.z80ne.com/eng/hardware.asp

 

Next article: 2006, Z80NE a second life >> articles

 

Clik on the pictures for an enlarged view.

04
The CPU board, complete with initial monitor EPROM.
(pict. Pino Giaquinto)
 
05
A new "old" initial setup quietly running.
(pict. by Pino Giaquinto)
 
06
The 32 KBytes dynamic memory expansion.
(pict.by Roberto Bazzano)

 

03
Floppy disk interface, FD1771 based with the socket
for newer monitor. (pict. R. Bazzano)
 
07
The 320x144 graphics interface (80x24 text mode).
(pict. by Roberto Bazzano)
 
08
The "terminal" like metal enclosure for video
lo-res, keyboard and floppy.

 

02
A typical enclosure with the system in the rack-mount
case. (pict. by Roberto Bazzano)
 
01
A more modern enclosure with four 3½" floppy drives.
(pict. by Pino Giaquinto)

 

Next article: 2006, Z80NE a second life >> articles

 

  Some picture courtesy Roberto Bazzano - The Home of Z80NE  

 

 

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under-construction

 

 

articles << Previous article: Z80NE 2006 a second life

 

 

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Please ask, if you wish an english translation added

 

original kit

Il mio Z80 NE

 a.k.a. ZDS or Z80 Darkstar

 

 

  

 

Il declino

Se avete letto l'articolo introduttivo alla Z80 di Nuova Elettronica, potete facilmente immaginare che, con il trascorrere degli anni, anche il buon vecchio Z80 andò in pensione.

Con l'arrivo in casa del primo PC IBM 8088, poi AT 286 e così via, di passo con la mia carriera professionale (oggi lavoro su cluster massivi), fu inevitabile che lo Z80 venisse progressivamente abbandonato. E così, anche se, nonostante la "concorrenza" di molto più performanti PC, la mia amata macchinina abbia caparbiamente proseguito la sua carriera per qualche anno con un programma di gestione abbonati per la rivista ferroviaria di mio padre scritto in DBII, fu inevitabile che infine trovasse la strada per la soffitta...

 

Tutti noi cresciamo negli anni e le prospettive cambiano. Così, ad un certo punto, come probabilmente è capitato a molti di voi, una maggiore disponibilità di tempo e una crescente nostalgia per i vecchi amori ha fatto sì che nascesse l'esigenza di "recuperare" il mio primo ed insostituibile computer.

2006, via la polvere!

Disceso dalla soffitta, non era messo poi tanto male, anche se recuperare i vari pezzi sparsi tra uno scatolone e l'altro non è stata impresa da poco.

A seguire le classiche operazioni di restauro, pulizia innanzitutto, verifica dell'alimentatore e prima ri-accensione. Sfortunatamente non ho fatto una documentazione fotografica di questa attività.

Quindi per farla breve il mio Z80 era di nuovo funzionante!

Bè non proprio.

Al primo tentativo di bootstrappare la macchina ho avuto la sgradita sorpresa di vedere che tutti i floppy del NE-DOS erano rovinati. Non solo quelli del NE-DOS a dire il vero, ma tutti in blocco, incluso quindi CP/M e qualsiasi altro software.

Sulla superficie dei floppy si era formata una specie di patina di muffa. Più tardi ho scritto un programmino per lo Z80 che fosse in grado di recuperare i settori non danneggiati. Visto che di molti floppy avevo copie multiple, in effetti, leggendo un settore da un disco, uno da un'altro, qualcosa sono riuscito a recuperare anche se questo purtroppo è quasi costata la vita ad uno dei drive Tandon da 5".

Tuttavia il problema immediato rimaneva: come caricare software sullo Z80?

All'epoca il sito di Roberto Bazzano, "The Home of Z80 NE", non esisteva e non ero ancora in contatto con altri affezionati dello Z80 NE. L'unica soluzione sembrava utilizzare la schedina parallela LX389 per realizzare una interfaccia parallela tra Z80 e PC. Anche perchè ormai il PC ospitava le immagini di tutti i dischi e il software per lo Z80 in mio possesso.

Fatta una piccola modifica su tale scheda e aggiunto il software necessario tutto si è sbloccato.

Da quel punto in poi sono nate tante idee, alcune realizzate, alcune ancora no (il tempo libero è quello che è). Non voglio annoiare nessuno e quindi vi risparmio la cronistoria delle modifiche apportate allo Z80 e del perchè alcune modifiche ne hanno richieste altre.

La documentazione del tutto è disponibile nelle pagine più in basso dove ho cercato spiegare le cose al meglio e nel dettaglio.

Qualche considerazione generale. 

Tutte le modifiche, alcune realizzate poi anche con l'aiuto dell'amico Pino Giaquinto portano ad avere uno Z80NE con gli "steroidi". Questo è bello da un lato ma comporta delle rinunce dall'altro.

Per chiarire: usare ad esempio la scheda multifunzione, che si porta a bordo 768k di ram, è possibile solo rinunciando alle schede di memoria originali. Ciò che alla fine ottenete non è più esattamente in linea con lo Z80NE, ma uno ZDS come io lo chiamo o Z80 Darkstar, nomignolo che il mio Z80 ha avuto praticamente da sempre, per via del suo case nero.

L'idea è avere lo Z80 dei miei sogni e vedere fin dove è possibile portare l'architettura di base di Nuova Elettronica, senza progettare un computer da zero, come per esempio hanno fatto i ragazzi del N8VEM.

Personalmente ho risolto il problema mettendo da parte tutto il "non serve più" e duplicando "il modificato" in modo da avere l'occorrente per uno Z80NE suo gemello, puro così come mamma lo ha fatto (grazie Pino per la scheda floppy...)

Una seconda importante considerazione è la seguente: tutto il software realizzato lato PC gira ed è stato sviluppato su Linux. Questo vuol dire che se non utilizzate questo sistema operativo vi dovrete attrezzare. Il software di per se è in puro C quindi non dovrebbe essere difficile il porting su DOS/Windows utilizzando Cygwin, ma io non l'ho mai fatto. Questo sforzo spetta a voi e anzi, se ci riuscite, This email address is being protected from spambots. You need JavaScript enabled to view it..

Tutto il software sviluppato, il software adattato (quasi tutto per il CP/M), la documentazione, i progetti e quant'altro è disponibile qui:

https://github.com/pbetti/ZDS

indipendentemente dalla descrizione dei singoli progetti che trovate sotto. Il materiale è disponibile su github sia per la facilità della distribuzione, sia perchè, bè, non ho mica smesso di lavorarci sopra... 😀

Per avere una copia del repository il requisito software è avere installato "git", che è disponibile su qualunque versione di Linux o che, a vostra scelta potete compilare prelevandolo da https://git-scm.com/downloads, quindi, posizionatevi in una cartella appropriata al contesto in cui creare la sottodirectory di github e date il comando:

$ git clone https://github.com/pbetti/ZDS.git

In seguito per mantenere il repo sempre aggiornato, entrate nella cartella ZDS ed usate il comando:

$ git pull origin master

Buon divertimento!

 

Progetti

Le modifiche realizzate e quelle in via di realizzazione sono documentate nella lista qui sotto. Cliccate sui titoli per la pagina corrispondente.

 

 Software, Tips&Tricks

 

  • La eprom da 4K e il SONE prima del SONE
  • Il CP/M 3 o CP/M+
  • Requisiti del sistema di sviluppo e HOWTOs