A Short History of the PC

1. A Short History of the PC

2. Prolog • Before the IBM, there were many PC vendors. • These were typically garage-shop start-ups with shaky financing. • The big names were Radio Shack and Apple. • Early personal computers were crude. • CPUs were 8-bit, usually and 8080 or Z80. • Storage was usually on audio cassette tape as diskette drives were expensive. • Monitors were TV sets with a maximum of 64 characters per line. • Printers were very expensive and often were upper-case only. • The big applications were WordStar and VisiCalc.

3. IBM PC – 1981

4. 1981 IBM PC Features • CPU – Intel 8088 • 16-bit CPU, 8-bit I/O, 4.77 MHz clock • 8-bit Industry Standard Architecture (ISA) expansion bus. • 16 K to 64 K RAM (up to 640 K with a RAM expansion card) • ROM BASIC • Operating systems • PC-DOS ($40) • CP/M ($450) • UCSD p-System ($550) • $1265 (plus monitor, video controller, operating system, serial port, floppy disk, and printer)

5. 1981 IBM PC Accessories • Displays • “High-resolution” character-only (80 per line) with a monochrome monitor. • Low-resolution graphics controller with a color display. • RAM cards were needed to expand memory beyond 64K. • Diskette drives held of 360 Kbytes. • Modems had speeds of 100 to 300 bps. • Printers used matrix-impact technology and ribbons.

6. IBM PC Open Architecture • IBM published its hardware interface specifications. • This allowed other companies to develop expansion cards, keyboards, mice, etc. • IBM decided that they would profit only from the hardware. • All software was developed by other companies. • IBM published its BIOS specifications. • As a result other companies reversed-engineered the BIOS, which allowed PC clones into the market. • IBM allowed Microsoft to sell DOS to others.

7. MS-DOS Screen

8. MS-DOS • The basic operating-system commands were in ROM so you could swap your program diskette with one containing data. • DOS contained few services. For example, an editor had to know how to control your printer. • Users had to configure peripherals (e.g., modems, ports, and printers) by editing control files, such as autoexec.bat and config.sys. • The simple software of the day easily fit on a360-K diskette.

9. IBM XT – 1983 • CPU – Intel 8088 • 16-bit processor, 8-bit I/O • 4.77 MHz clock • 8-bit ISA bus • 256 K or 640 K RAM in 36 DIP sockets • 360K, 5-¼” diskette (720K, 3-½” optional) • 10 or 20 Mbyte hard disk • $5000 (with a 10-MB disk) • Other manufacturers began to enter the PC market.

10. IBM AT – 1984 • CPU – Intel 80286 • 16-bit processor, 16-bit I/O • 6 or 8 MHz clock • 16-bit ISA bus • 512 K on motherboard, 16M maximum • 1.2M, 5-¼” diskette (1.44M, 3-½” optional) • 20 or 30 Mbyte hard disk • EGA graphics • $6000 with a 20 Mbyte disk

11. Hardware Milestones • 1982 – Compaq “Portable” (28 lbs., ac power) • 1984 – HP introduces the laser printer. • 1985 – 2400 bps modems become common; the 16-MHz 80386 appears. • 1986 – Compaq releases the first 80386 PC. • 1987 – VGA graphics (640480) appear. • 1990 – Intel introduces the 80486 with an integrated co-processor. • 1993 – The Intel Pentium debuts at 60 MHz; the PCI bus appears.

12. DOS Milestones • 1981 - DOS 1 (purchased from Seattle Computing for $50,000) • 1983 – DOS 2 (subdirectory and 10-MB hard disk support) • 1984 – DOS 3 (1.2-MB diskette and 32-MB hard disk support) • 1988 – DOS 4 (too buggy to be popular) • 1991 – DOS 5 (allowed the use of 640-1024K RAM and larger disks, added a disk cache and undelete) • 1993 – DOS 6 (disk compression and defragging, better memory management)

13. Windows 1.0 Screen

14. MS Windows Milestones • 1985 – Windows 1.0 (a DOS shell, crude and slow) • 1987 – Windows 2.0 (icons, overlapping windows) • 1990 – Windows 3.0 (16 colors, new file manager, the first successful version) • 1992 – Windows 3.1 (drag-and-drop, better integration) • 1995 – Windows 95 (long filenames, dial-up networking) • 1998 – Windows 98 (USB support, Internet Explorer 4 built- in) • 2001 – Windows XP (32-bit architecture, DOS independence)

15. Epilog