View Full Version : IBM PC (5150)

February 13th, 2010, 02:50 PM
The IBM PC 5150 was the first personal computer produced by IBM. It was based on the Intel 8088 CPU and it started the PC revolution.
thumb|right|An IBM 5150 with monochrome monitor and [[Windows 1.01]]
An Intel 8088 running at 4.77MHz
Minimum of 16KB on the motherboard, expandable to 64KB on the motherboard
Microsoft BASIC built into ROM
Five internal expansion slots
Cassette port
83 key keyboard
Room for two full height 5.25 inch floppy drives
63 watt power supply

To make a minimal usable machine one had to select a video card and a monitor. The choices available at the time were a Monochrome Display Adapter (MDA) or a Color Graphics Adapter. Most machines were sold with more memory on an expansion card and at least one diskette drive.

The diskette drives on the initial systems were single sided and held 160KB of storage per diskette side. Later models used double sided diskette drives and changed the number of sectors per track to 9 for a total of 360KB per diskette. The floppy drive controller was capable of driving two internal diskette drives and two external diskette drives through an external 37 pin port located on the card bracket.

The IBM PC 5150 has two hardware versions and three BIOS versions. The first hardware version allowed for up to 64KB on the motherboard. The second hardware version allowed for up to 256KB on the motherboard. The BIOS versions are:
Release 1: 04/24/81
Release 2: 10/19/81
Release 3: 10/27/82

IBM discontinued the IBM PC 5150 in 1987.
Further Reading
The Wikipedia.org article on the IBM 5150 (http://en.wikipedia.org/wiki/IBM_PC)

External Links:
The Vintage Computer Forums thread on the IBM 5150 BIOS revisions (http://www.vintage-computer.com/vcforum/showthread.php?t=9692)