Global MicroComputer Specifications
The table below shows the technical characteristics of some old computers, like the type of CPU unit, RAM memory capacity, ROM capacity which stored the basic firmware or Operating system, and dedicated Video RAM for graphics display.
The latter was quite important, because the more video RAM (VRAM) there was, the better the graphics were.
In the early 80s, a personal computer that could use 16kb of VRAM was a very good machine! Now nobody wants a GPU with less than 4GB of RAM :D
The ROM is now a bit like the Flash we have on our phones, except that the firmware or OS was not updated as easily, as it was not erasable.
If you find any inaccuracies, or if you have any questions about retro computing, please leave me a message below.
| Brand/Model | Country | Year | Units Sold | CPU | Coprocessors | RAM | ROM | VRAM |
| Commodore VIC20 | US | Sept. 1980 | 2.5 million | MOS 6502 @ 1.02Mhz | - | 4 KB | 20 KB | 1 KB |
| Sinclair ZX81 | UK | March 1981 | +1 million |
Zilog Z80 @ 3.25Mhz | - | 1 KB (up to 64KB) | 8 KB | |
| TI 99/4A | US | June 1981 | 2.8 million |
TMS9900 @ 3Mhz | - | 256 bytes 16bits (up to 32KB) | 26 KB | 16 KB |
| Commodore 64 | US | Sept 1982 | 22 million |
MoS 6510 @ 0.985 MHz | - | 64 KB | 16 KB (20KB for the 64C) | up to 20KB of RAM used |
| Apple IIe | US | Jan 1983 | MoS 65c02 @ 1Mhz | - | 64KB | 16KB | up to 16KB of RAM used | |
| Tandy/RS TRS 80 CoCo II | US | Sept 1983 | Motorola 6809E @ 0.895 MHz | |
16 KB | 16 KB | |
|
| Micronique Hector HRX | FR | Aug 1983 | Zilog Z80A @ 5Mhz | - | 64KB | 16KB | |
|
| Atari 800 XL | US | Dec 1983 | MoS 6502C @ 1.77 MHz | - | 64KB | 24KB | up to 8KB of RAM used | |
| ORIC Atmos | UK | 1984 | MoS 6502A @ 1 MHz | |
48 KB | 16 KB | 8 KB of RAM used | |
| Thomson MO5 |
FR |
1984 |
Motorola 6809e @ 1Mhz |
- |
32 KB |
16 KB |
||
| Philips VG8020 msx | NL | 1984 | Zilog Z80 @ 3.58MHz | - | 64 KB | 32 KB | 16 KB | |
| VTECH Laser 310 | HK | 1984 | Zilog Z80 @ 3.58MHz | - | 16 KB | 16 KB | 2 KB | |
| Exelvision EXL100 |
FR |
1984 |
TI tms 7041 + tms 7020 @ 4.91 MHz | - |
32 KB up to 290 |
4 KB |
||
| Commodore 128 | US | 1985 | 4 million |
MOS 8502 @ 1.97/0.985MHz + Zilog Z80A @ 4Mhz |
- | 128 KB | 64 KB | 16KB + up to 20KB of RAM used |
| Thomson MO6 | FR | 1986 | Motorola 6809e @ 1MHz | - | 128 KB | 64 KB | 16 KB of RAM used | |
| Sinclair ZX Spectrum 2+ | UK | 1987 | . | Zilog Z80A @ 3.54Mhz | - | 128 KB | 32 KB | 7 KB of RAM used |
| Amstrad 6128 plus | UK | 1987 | Zilog Z80A @ 4MHz | - | 128 KB | 128 KB (64 KB used by a demo game!) | 16 KB of RAM used | |
| Atari 520 STf | US | 1987 | Motorola 68000 @ 8MHz | - | 512 KB | 192 KB | 32 KB of RAM used | |
| Macintosh II |
US |
1987 |
|
Motorola 68020 @ 16Mhz |
68881 FPU |
1 MB |
256 KB |
external video card (300 KB typ.) |
| Commodore Amiga 600 | US | march 1992 a500+;August 1990 | 5 million (all Amigas) |
Motorola 68000 @ 7.14MHz | - | 1 MB | 512 KB | up to 1 MB of RAM used (2 MB with extension) |
| Apple Macintosh SE30 | US | 1991 | Motorola 68030 @ 15.77Mhz | 68882 FPU | 4 MB | 256 KB | |
Books
If you're interested in Retrocomputing, I would also recommend reading the following books. I find very interesting how these computer industry pioneers, with brilliant ideas, made history and begun to earn millions of dollars !
Sound, Graphics, I/O
The table below gives more details about the graphics and sound capabilities of old computers.
Multimedia capabilities started to be much better, around 1985, when the 1st mass produced 16/32 bits computers were introduced. Specialized processors were often in charge of displaying and moving quickly bitmaps for games (BIT BLT column), to ease the task of the main micro-processor.
| Brand/Model | Text Modes | Graphics Modes | BIT BLT/Sprites | Sound | |
|
I/O ports |
| Commodore VIC20 | - 22x23 8 colours | - 176x184 16 colours |
none | 3 voices (square wave), noise and volume | |
Video composite, 1 Joystick, Cardridge, Tape, Serial, User Port (RS232 compatible) | |
| Sinclair ZX81 | - 32x22 B/W | - 64x44 B/W - 256x182 B/W with 16KB RAM expansion |
none | none | |
RF video, Expansion slot, Tape | |
| TI 99/4A | - 40x24 B/W | - 32x24 16 colors - 256x192 16 colors, 2 colors per 1x8 block - 64x48 16 colors |
32 sprites | TMS9919 3 voices, 1 noise | |
ROM cartridge, tape, Audio/Video output, Joystick, bus expansion | |
| Commodore 64 | - 40x25 16 colors | - 320x200 16 colors (1 color per 8x8 block) - 320x200 16 colors (1 color per 1x8 block) - 160x200 16 colors (4 colors per 4x8 block) - 160x200 16 colors |
yes | SID 6581: An advanced 3 voices synthetizer | |
|
Video composite, Joystick x2, Cardridge, Tape, Serial, User Port (RS232 compatible) |
| Apple IIe | - 40x24 - 80x24 (with 80 columns card) |
- 40x48 16 colors - 280x192 6 colors with constraints - 560x192 16 colors with constraints |
none | 1 channel | |
|
Composite video, Internal slots *7, Tape, Joystick *2 |
| Radio Shack TRS 80 CoCo II | - 32x16 8 colors | - 32x16x8 colors - 64x32x8 - 128x96x2 or 4 - 128x192x2 or 4 - 256x192x2 |
none | 1 voice | |
|
Tape, RGB, Joystick x2, Cardridge, Serial RS232 |
| Micronique Hector HRX | - 40 x 24 4 colors | - 243 x 231 4 colors. 15 colors palette | none | 1 voice | |
|
RGB, Centronics, Cardridge, Joystick * 2 |
| Atari 800 XL | up to 40 x 24 5 colors 256 colors palette |
- up to 320 x 192 1 color - up to 160 x 192 4 colors - up to 80 x 192 16 colors 256 colors palette, flexible video chip (ANTIC) |
4 sprites 8x256 1 color, 4 sprites 2x256 1 color, H/V scrolling | Atari POKEY, 4 voices | |
|
Composite Video, Bus, Cardridge (16KB), Joystick * 2, Tape+Serial Bus |
| Oric Atmos | 40 x 28 8 colors | 240 x 200 8 colors with constraints (hard to display more than two colors per line) | none | 3 voices: AY-3-8912 | |
|
RBG, RF video, Bus, Printer, Tape |
| Thomson MO5 | - 40 x 24 | - 320 x 200 16 colors (1 color
per 1x8 block) |
none |
1 voice (8 bits DAC) | RGB (Scart), Light Pen, Tape Cardridge, Bus | ||
| Philips VG8020 msx | 40 x 24 16 colors | 256 x 192 16 colors with constraints | yes | 3 voices: YM-2413 | |
|
RGB, Centronics, Cardridge *2, Tape, Joystick *2 |
| VTECH Laser 310 | - 32 x 16 9 colors | - 64 x 32 9 colors - 128 x 64 8 colors |
none | beeper, 1 voice | |
|
RGB, Tape, Centronics (opt), Expansion bus |
| Excelvision EXL100 |
- 80x25 |
- 320x250 8 colors |
? |
Vocal synthetizer |
IR joystick+keyboard,
centronics, bus, RAM ROM ext, tape |
||
| Commodore 128 | - 40x25 16 colors - 80x25 16 colors - 80x50 16 colors |
- 640x200 16 colors (1 color per 8x8 block) - 320x200 16 colors (1 color per 8x8 block) - 320x200 16 colors (1 color per 1x8 block) - 160x200 16 colors (4 colors per 4x8 block) - 160x200 16 colors |
yes | SID 6581: An advanced 3 voices synthetizer | |
|
RGBI, Video composite, Joystick x2, Expansion port, Tape, Serial, User Port (RS232 compatible) |
| Thomson MO6 | - 80 x 24 - 40 x 24 |
- 160 x 200 16 colors - 320 x 200 16 colors (1 color per 1x8 block) - 640 x 200 2 colors 4096 colors palette |
none | 1 voice (8 bits DAC) | |
|
RGB (Scart), Light Pen, Joystick, Mouse, Centronics, Cardridge, Stereo, Bus |
| ZX Spectrum 2+ | - 32x22 8 colors | - 256x192 8 colors (1 background/foreground by 8x8 block) | no | 3 voices: AY-3-8912 + 1 bit audio |
|
|
Z80 Bus, Numeric Keyboard, RS232 or Midi Out, Audio, RGB, 2 x Joystick |
| Amstrad 6128 plus | - 40 x 25 - 80 x 25 - 20 x 25 |
- 160 x 200 16 colors (32 colors with sprites) - 320 x 200 4 colors (20 colors with sprites) - 640 x 200 2 colors 27 or 4096 colors palette |
16 sprites (16 x 16 15 colors each in any graphics mode, XY x1 x2 x4 magnification), hardware scrolling, horizontal split screen with independent scrolling | 3 voices: AY-3-8912 + possibility to stream data without CPU intervention | |
|
RGB, Centronics, Z80 Bus, Joystick x 2, 1 Analog Joystick (SUB-D 15), Light gun (RJ-11), Disk unit, Tape, ROM Cardridge (up to 512 KB) |
| Atari 520 STf | - 40 x 25 - 80 x 25 |
- 320 x 200 16 colors - 640 x 200 4 colors - 640 x 400 B/W 512 colors palette |
NO (Appeared on the MegaST and STe) | 3 voice: YM-2149 | |
|
RGB, Cardridge, Midi in and out, Centronics, RS232c, Hard Disk, Floppy disk, Joystick, Mouse |
| Macintosh II |
- 640x480 256 colors (external
video card) |
Depends on video card |
Stereo 8 bits |
ADB x2, Serial x2, 6 Nubus
slots, 2 integrated FD |
|||
| Amiga 600 | - VERY flexible PAL/NTSC chip - up to 320 x 512 from 2 to 64 or 4096 colors - up to 640 x 512 from 2 to 16 colors - up to 1280 x 512 2 or 4 colors - 4096 colors palette. - overscan, dual video output | Yes | 4 stereo channels 8 bit (28 or 56 Khz sampling rate) | |
|
Analog RGB, Composite Video, 2 Stereo Audio RCA, 1 parallel port, PCMCIA T1, 1 internal slot, Mouse/Game port x2, RS-232 (DB-25), External Floppy, | |
| Apple Macintosh SE/30 | - | 512 x 342 B/W | none | 1 voice (22Khz / 8 bits DAC) | |
|
RS232/422 *2; ADB *2 (keyboard, mouse), Stereo, Floppy disk, SCSI, 68030 Processor Direct Slot |
Sound chip specs
Since first micro-processors were not fast enough to handle graphics, sounds, and calculations at the same time, the best old computers were equipped with co-processors dedicated with sound generation.
The AY-3-8910, created in 1978, was one of the most popular of them, and was used in many arcade games, pinball machines, game consoles and 8-bits home computers, like the Amstrad CPC, Oric-1, MSX, Sinclair ZX Spectrum.
Here is some of the most frequently used sound generators found in home computers:
→ AY-3-8912: 3 voices 9 octaves 16 volume levels, 1
noise generator, 10 fixed enveloppe paterns (but with programmable
period). It's the same chip as the AY-3-8910, but with less I/O ports.
→ YM-2149: 3 voices 8 octaves 32 volume levels, only 1 waveform (square
wave), 1 noise generator, 10 fixed enveloppe
paterns. similar to AY-3-8912.
→ SID 6581: 3 oscillators (0-4Khz), 4 waveforms per oscillator (Triangle,
Sawtooth, Variable Pulse, Noise), 3 amplitude modulators (8 bits), 3
envelope generators (Full ADSR), ring modulation, programmable filter
(low pass, Bandpass,High pass, Notch with variable resonance), one
channel can be used as a 12 bits PWM (12 bits digital sound in 1983
!!!).
→ YM-2413: FM synthetizer, 9 poly channel or 6 channels and 5 rythm
sounds. Built-in instruments: 15 melody tones, 5 rhythme tones. 1
programmable instrument (ADSR).
→ Atari POKEY: 4 voices of 8-bit pitch-resolution, 4-bit
volume-resolution,
8-distortion sound can be produced. 2 voices (1 and 2, and/or 3 and 4)
can be combined to make 16-bit pitch-resolution. Also 4-bit volume-only
modes can be enabled for digitally sampled sound replay.
Obsolete Microprocessors
I also tried to estimate to power in MIPS of these old processors using the theorical cycles needed for basic machine language instructions.
| Brand/Model | Year | Type | Typ. Freq. | Registers | Imm. Load | Mem. Load | And | Imm. And | Incre- ment | Imm. Sub- stract | Compa- rison | Condi- tionnal Jump | Stack Push | Estimated Power |
| Zilog Z80 | July 1976 | 8 bits | 4-8 Mhz | 1 x 8bits 3 x 16bits (or 6 x 8 bits) 2 x 16bits index (double all these numbers if you count shadow registers) |
7 (10*) | 7 (16*) | 4 | 7 | 4 | 7 | 7 | 12-7 | 11* | 0.58 MIPS @4Mhz |
| MoS 6502 | 1975 | 8 bits | 1-2 Mhz | 1 x 8bits** 2 x 8bits index |
2 | 3-4 | 2 | 2 | 2 | 2 | 2 | 2-3 | 4 | 0.43 MIPS @1Mhz |
| Motorola 6809 | 1977 | 8 bits | 1 Mhz | 2 x 8bits (or 1 x 16bits) 2 x 16bits index |
2 | 4 | 2 | 2 | 2 | 2 | 2 | 3 | 5 | 0.42 MIPS @1Mhz |
| TI TMS 9900 | June 1976 | 16 bits | 3 Mhz | 3 x 16bits 256 x 16bits in fast ext RAM |
0.1-0.2 MIPS @3Mhz | |||||||||
| Intel 8086/8088 | 1978 | 16 bits | 8 Mhz | 4 x 16bits (or 8 x 8bits) 4 x 16bits index 4 x segment |
4 | 14 | 3 | 4 | 2 | 4 | 3 | 16 | 8 | 1.2 MIPS @8Mhz*** |
| Motorola 68000 | Sept 1979 | 16/32 bits | 8 Mhz | 16 x 32bits | 4/8 | 8 | 4 | 8 | 4 | 4/8 | 4 | 10/8 | 8 | 1.4 MIPS @8Mhz |
**: Only one register but fast access to the 1st 256 bytes of memory. So the 6502 was close to having 256 registers
***: speed for the 8086. On the 8088 you will get only 60-70% of this speed because of the 8 bits bus and the smaller prefetch buffer.
68000: because of 68000 transistors ;)
Links
Planet Sinclair by Chris Owen
Atari Historical Society's virtual Atari museum
Atari Archives
Please, comment below