ZVT SPU-800

ZVT SPU-800 Also called Systém Pořizování Údajů,TP8.Designed by Ing. Pavel Sedláček.It was manufactured from 1979 (it could have been introduced, the development was definitely taking place) by ZVT B.Bystrica. Hardware is based on 74181 @ 10 MHz.Operating systems running on the computer: SPUAS,MKOS-1.

This topic contains doubts or inaccuracies that need to be corrected. More information follows below.

Parts of this topic may be machine translated.

Contents

TP8 Processor Cards

The entire processor is built on TTL 74xx series circuits, so there is no microprocessor in the modern sense of the word.

The front panel is labeled RPL (Control Panel), it is connected to the TP8 bus using individual wires (wound connections).

The model of the processor will probably be some calculator from HP, I guess according to the bus terminology - signals /SIH, /CEO, SP-ScratchPad can be found e.g. in HP9830 or in patent US4012725A.

Bus Expanders

Universal basting plates

It is a board with an array of connections with a metric pitch of 2.5 mm. According to the photos, these boards were apparently quite actively used for various specific applications where it was not appropriate to use any existing peripheral board.

(it is also possible to use TNS-BASTL, which was created later)

Memory cards

They plug into the ZPP part of the SPU-800 like other peripheral cards

The cards can be addressed in the entire 64kB address space of the processor. At least one P1K card usually contains a Boot ROM, e.g. to read another code from the punched tape.

According to available unverified information for the SPU-800 there was also a set of complete controller cards with DRAM memory (cards PMT 7CB 006 275, GAD 7CB 006 276 and RSP 7CB 006 277).

Peripheral Cards

They connect to the ZPP part of the SPU-800

Front Panel Description

LED indication:

Functions (buttons):

Program Counter, ACC, PHASE, CARRY are displayed dynamically while the processor is running (LEDs flash)

ZPP bus

The bus is I/O compatible with 8-bit TNS.

MI[0..7] memory IN
MO[0..7] memory OUT
MW Memory Write
CO[0..3] I/O select CODe
SO[0..3] I/O Status OUT
SI[0..3] I/O Status IN
DI[0..7] I/O data IN
TO[0..7] I/O data OUT
/SIH Service INhibit
/CEO Control-Enable-Output

Modern developments

Using the SPU-800

Terminal Workplace

In 2023, Martin Bílý shared about the use of SPU-800 at CTU FEL: "I knew this as, let's say, an educated user sometime around 1985. I encountered it in, let's say, terminal workstation mode. Four workstations, character screen, keyboard. Connected via domestic modems via a common landline to the parent computer. Modems the size of a shoebox, apparently it was MDS 1200. There was a protocol for addressing individual workplaces on that line. I probably knew it in detail then. I vaguely suspect that the text of the entire line was being scrolled. There was no such thing as a teletype mode. It was not very comfortable to edit files in line mode combined with sharing a slow shared line meant that users only used it in emergencies when they didn't want to wait for "normal" terminals to become available.

In the deployment known to me, it was about expanding the number of user workstations of the ICL-2904 minicomputer. The communication line was a piece of cable, the modems for both ends were on top of each other in the table of one of those workplaces. I don't know why modems were used there. Perhaps that ICL computer required a full and true serial interface on its interface with all control signals and their timings.

I have no idea what the typical use of the SPU-800 was, how and what it was programmed into. In my case, the assembly worked at the imaginary turn of the mains switch."

In a treatise on the history of the use of computer technology at the FE BUT in Brno, he states about SPU-800: "The first terminal classroom was a classroom built on the SPU 800 system... The terminal classroom was connected to the ADT 4316 minicomputer via the TC-99 serial communication protocol, its use began in 1983. The SPU 800 system consisted of a TP8 terminal processor, 9 expanders, with which it was possible to increase the number of connected devices and individual workplaces.In our terminal classroom, these devices were alphanumeric display units AZJ 6416 also produced in ZVT Banská Bystrica [...]

It can be said that during the development of the terminal classroom, a typical feature of that time manifested itself - our workplace had to develop the necessary technical and software equipment on its own. It was a time when devices appeared on the market whose deployment in a specific application was solved by their users themselves. Our workplace was able to implement such activities."

Data acquisition

Control computer

EPROM programmer (see AMARO in references)

Management of technological processes

Data acquisition

Peter Šindler states in private correspondence (2024/05) about the use of the SPU-800:

"An interesting deployment of SPU-800 was in Žiar nad Hronom in an aluminum smelter, where a network of SPU-800s (perhaps 10 units) was connected to SM 4-20 and SPU-800s were connected to furnaces for the production of aluminum, where it was determined whether the so-called skin-effect – the emergence of an electrode from liquid aluminum – and the time it took the operator to react rewards. In the beginning it turned out badly, because the operator did not react, which caused very large energy losses. While they got used to it, there was also damage to the computer equipment..."

Software

COUNTDOWN Test App

The program for the punched tape, which is loaded by the standard loader from the SDP card to address 0170000 (0xF000) and counts slowly on the ACC front panel display from 0377 to 0000, the BASE64 encoded content of the punched tape follows:

📋ADwAOfAA/wBlZv//YwAAAAAAAAAAAA
AAAAAAAAAAAAAAANiVGmVTsTAH/9tl
lhpmU7EwB9STFWOyMAfYvUAwAADo

Unknown derived computers

Inaccuracies/doubts related to the topic

Unknown predecessor - "inspirational model" (probably from Hewlett-Packard)

If you have information on the ''Unknown Derived Computers'' chapter.

Insecure controller with DRAM memory.

If anyone has more information, please get in touch.

Computers derived from ZVT SPU-800

The following computers were inspired by or derived from ZVT SPU-800:

References

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