Orao ( en. ''Eagle'') was an 8-

bit The bit is the most basic unit of information in computing and digital communications. The name is a portmanteau of binary digit. The bit represents a logical state with one of two possible values. These values are most commonly represente ...

computer A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as C ...

developed by ''PEL

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'' in 1984. Its marketing and distribution was done by ''Velebit Informatika''. It was used as a standard

primary school A primary school (in Ireland, the United Kingdom, Australia, Trinidad and Tobago, Jamaica, and South Africa), junior school (in Australia), elementary school or grade school (in North America and the Philippines) is a school for primary e ...

and

secondary school A secondary school describes an institution that provides secondary education and also usually includes the building where this takes place. Some secondary schools provide both '' secondary education, lower secondary education'' (ages 11 to 14) ...

computer in the former

Yugoslavia Yugoslavia (; sh-Latn-Cyrl, separator=" / ", Jugoslavija, Југославија ; sl, Jugoslavija ; mk, Југославија ;; rup, Iugoslavia; hu, Jugoszlávia; rue, label=Pannonian Rusyn, Югославия, translit=Juhoslavija ...

(

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = "Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capit ...

and

Vojvodina Vojvodina ( sr-Cyrl, Војводина}), officially the Autonomous Province of Vojvodina, is an autonomous province that occupies the northernmost part of Serbia. It lies within the Pannonian Basin, bordered to the south by the national capital ...

) from 1985 to 1991. Orao (code named YU102) was designed by Miroslav Kocijan to supersede Galeb (code named YU101). The goal was to make a better computer, yet with less components, easier to produce and less expensive. The initial version, dubbed ''Orao MR102'', was succeeded by ''Orao 64'' and ''Orao+''.

History

The chief designer of Orao was Miroslav Kocijan, who previously constructed the basic motherboard for Galeb (working name YU101). Galeb was inspired by computers

Compukit UK101 The Compukit UK101 microcomputer (1979) is a kit clone of the Ohio Scientific Superboard II single-board computer, with a few enhancements for the UK market - notably replacing the 24×24 (add guardband kit to give 32×32) screen display with a ...

, Ohio Scientific Superboard and Ohio Scientific Superboard II which appeared in the United Kingdom and the United States in 1979 and were cheaper than the Apple II, Commodore PET and TRS-80. Driven by the challenge of Anthony Madidi, Miroslav Kocijan began to develop a computer that is supposed to be more advanced than the Galeb with fewer components, easier to produce, better graphics, performance and a more affordable price. The working title of the new project was YU102. Miroslav Kocijan managed to gather around him a group of people who helped in the development of electronic components and software. Kocijan had the idea to commercialize Orao, and was able to convince Rajko Ivanusic, director of ''PEL Varaždin'', to support the idea. In the market of the former Yugoslavia, where the purchase of home computers were disabled due to high tariffs and due to the low purchasing power of citizens and schools computers were unattainable, the idea of mass-produced home computers made sense.

Serial production and price

The price of Orao was originally set to be around 55.000

Yugoslav dinars The dinar (Cyrillic script: динар) was the currency of the three Yugoslav states: the Kingdom of Yugoslavia (formerly the Kingdom of Serbs, Croats and Slovenes), the Socialist Federal Republic of Yugoslavia, and the Federal Republic of Yu ...

, however the price rose to 80.000 dinars. The production began in the summer of 1984. Since the only imported components were integrated circuits which were hard to acquire in Yugoslavia because of strict monetary politics, ''PEL Varaždin'' itself financed the imports of these components, which enabled a cheaper final product. Occasional problems that occurred in the serial production were related to the construction of certain external parts and overheating.

Lack of supported software

Since the Orao was not compatible with any home computer of the time, its software offering was scarce due to the lack of software companies whose products supported the platform.

Lack of capabilities

That was one of the most common sentences related to 8-bit school computer. Result of that statement is chapter above.

Architecture

The graphics were controlled by a special circuit, not by the main processor as it was the case in many other home computers because Kocijan's intention was to create a graphical computer similar to

Xerox Alto The Xerox Alto is a computer designed from its inception to support an operating system based on a graphical user interface (GUI), later using the desktop metaphor. The first machines were introduced on 1 March 1973, a decade before mass-market G ...

, or

Macintosh The Mac (known as Macintosh until 1999) is a family of personal computers designed and marketed by Apple Inc., Apple Inc. Macs are known for their ease of use and minimalist designs, and are popular among students, creative professionals, and ...

, and as such, he had it utilize bitmap graphics. The resolution was 256x256 dots, for up to 196,608 bits of VRAM as the graphics could need no more than three bits per pixel. Such a resolution was chosen for square dots, which enabled easy writing of graphical programs. The resolution of text was 32x32, and every character was rendered in an 8x8 field. The designers of Orao went an additional step further to create a computer which could be far more easily expanded, connect with a printer and establish a net connection through

RS-232 In telecommunications, RS-232 or Recommended Standard 232 is a standard originally introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' (''data terminal equipment'') such a ...

Specifications

CPU A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and ...

MOS Technology 6502 The MOS Technology 6502 (typically pronounced "sixty-five-oh-two" or "six-five-oh-two") William Mensch and the moderator both pronounce the 6502 microprocessor as ''"sixty-five-oh-two"''. is an 8-bit microprocessor that was designed by a small t ...

at 1

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

Read-Only Memory Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM cannot be electronically modified after the manufacture of the memory device. Read-only memory is useful for storing sof ...

: 16 KB (with

BASIC BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...

interpreter and

Machine code monitor A machine code monitor ( machine language monitor) is software that allows a user to enter commands to view and change memory locations on a computer, with options to load and save memory contents from/to secondary storage. Some full-featured m ...

) *

RAM Ram, ram, or RAM may refer to: Animals * A male sheep * Ram cichlid, a freshwater tropical fish People * Ram (given name) * Ram (surname) * Ram (director) (Ramsubramaniam), an Indian Tamil film director * RAM (musician) (born 1974), Dutch * Ra ...

: 16 KB (expandable to 32 KB) * VRAM up to 24 KB *

Graphics Graphics () are visual images or designs on some surface, such as a wall, canvas, screen, paper, or stone, to inform, illustrate, or entertain. In contemporary usage, it includes a pictorial representation of data, as in design and manufacture ...

monochrome A monochrome or monochromatic image, object or palette is composed of one color (or values of one color). Images using only shades of grey are called grayscale (typically digital) or black-and-white (typically analog). In physics, monochrom ...

256×256 pixels, in up to 8 shades of gray *

Text mode Text mode is a computer display mode in which content is internally represented on a computer screen in terms of characters rather than individual pixels. Typically, the screen consists of a uniform rectangular grid of ''character cells'', each ...

: 32 lines with 32 characters each * 72 chars in one BASIC line * Sound: single-channel, 5

octave In music, an octave ( la, octavus: eighth) or perfect octave (sometimes called the diapason) is the interval between one musical pitch and another with double its frequency. The octave relationship is a natural phenomenon that has been refer ...

s through built-in

loudspeaker A loudspeaker (commonly referred to as a speaker or speaker driver) is an electroacoustic transducer that converts an electrical audio signal into a corresponding sound. A ''speaker system'', also often simply referred to as a "speaker" or " ...

Computer keyboard A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology ...

: 61-key

QWERTZ The QWERTZ or QWERTZU keyboard is a typewriter and keyboard layout widely used in Central Europe. The name comes from the first six letters at the top left of the keyboard: ( ). Overview The main difference between QWERTZ and QWERTY is tha ...

I/O port Memory-mapped I/O (MMIO) and port-mapped I/O (PMIO) are two complementary methods of performing input/output (I/O) between the central processing unit (CPU) and peripheral devices in a computer. An alternative approach is using dedicated I/O pro ...

s: video and RF

TV out The term TV-out is commonly used to label the connector of equipment providing an analog video signal acceptable for a television AV input. TV-out is different from AV-out in that it only provides video, no audio. Types of signals and their re ...

cassette tape The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Ottens ...

interface ( DIN-5),

(D-25), Edge expansion connector *

Peripheral A peripheral or peripheral device is an auxiliary device used to put information into and get information out of a computer. The term ''peripheral device'' refers to all hardware components that are attached to a computer and are controlled by the ...

s: 5.25" floppy drive,

Printer Printer may refer to: Technology * Printer (publishing), a person or a company * Printer (computing), a hardware device * Optical printer for motion picture films People * Nariman Printer ( fl. c. 1940), Indian journalist and activist * Jame ...

* Price: 55,000

dinars The dinar () is the principal currency unit in several countries near the Mediterranean Sea, and its historical use is even more widespread. The modern dinar's historical antecedents are the gold dinar and the silver dirham, the main coin of ...

planned but increased to 80,000 during production

BASIC example

Math

10 REM PLOTS ONE PERIOD OF SINUS GRAPH 20 for x=0 to 128 30 y=64*sin(3.14159*x/64) 40 plot x,y+96 50 next 60 END

Physics

5 REM CONVERTS KM/H TO M/S 10 PRINT"KM/H M/S" 20 FOR SP=0 TO 60 30 PRINT SP,SP*1000/(60*60) 40 NEXT Output RUN KM/H M/S 0 0 1 .277777778 2 .555555556 3 .833333333 4 1.11111111 5 1.38888889 6 1.66666667 7 1.94444445 8 2.22222222 9 2.5 10 2.77777778 11 3.05555556 12 3.33333333 13 3.61111111 14 3.88888889 15 4.16666667 16 4.44444445 17 4.72222222 18 5 19 5.27777778 20 5.55555556 21 5.83333334 22 6.11111111 23 6.38888889 24 6.66666667 25 6.94444445 26 7.22222223 27 7.5 28 7.77777778 29 8.05555556 30 8.33333333 31 8.61111112 32 8.88888889 33 9.16666667 34 9.44444445 35 9.72222223 36 10 37 10.2777778 38 10.5555556 39 10.8333333 40 11.1111111 41 11.3888889 42 11.6666667 43 11.9444444 44 12.2222222 45 12.5 46 12.7777778 47 13.0555556 48 13.3333333 49 13.6111111 50 13.8888889 51 14.1666667 52 14.4444444 53 14.7222222 54 15 55 15.2777778 56 15.5555556 57 15.8333333 58 16.1111111 59 16.3888889 60 16.6666667

Machine code/Assembly example

1000 A9 7F LDA #7F 1002 85 E2 STA E2 ; x center 1004 85 E3 STA E3 ; y center 1006 A9 6F LDA #6F 1008 85 F8 STA F8 ; radius 100A 20 06 FF JSR FF06 ; draw circle 100D C6 E2 DEC E2 ; decrement x center 100F C6 E3 DEC E3 ; decrement y center 1011 A5 F8 LDA F8 1013 38 SEC 1014 E9 04 SBC #04 ; reduce radius for four points 1016 85 F8 STA F8 ; store it 1018 C9 21 CMP #21 ; compare with 0x21 101A B0 EE BCS 100A ; bigger or equal ? yes, draw again 101C 60 RTS ; no, return

Design team

* Miroslav Kocijan * Branko Zebec * Ivan Pongračić * Anđelko Kršić * Damir Šafarić * Davorin Krizman * Zdravko Melnjak * Vjekoslav Prstec * Dražen Zlatarek

References

External links

Orao page at old-computers.com

Orao implementation
in

FPGA A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturinghence the term '' field-programmable''. The FPGA configuration is generally specified using a hardware de ...

Another Orao implementation
in

MESS, Multi-System Emulator which supports Orao

Orao emulator with source code and some software, as well as Orao 2007 recreation of original computer

Orao Emulator written in C#

Orao Emulator for Android

ORAO BASKET

Orao Emulator in web browser

Orao Emulator in Python

Browser Orao Emulator as standard web site, using Blazor/C#

Browser Orao Emulator as Web Assembly app, can work offline in modern browsers
{{Croatian computers Computer-related introductions in 1984 Personal computers