Z-100 is an early microcomputer manufactured by Zenith Data Systems . In fact, it was the renamed microcomputer Heathkit H-100. It was sold as a kit of parts Heathkit (shortly before that was acquired by Zenith Electronics and became Zenith Data Systems) H-100, which left the stage of final assembly to computer enthusiasts.
The Z-100 computers in the first half of the 1980s , in the era of personal computers , were one of the first alternatives to the heirs of IBM PC / XT / AT or the computer families that conquered the market. It was conceived as a family: Z-120 (all-in-one model, with a monitor in the case), Z-110 (low-profile model), was similar in size to the cases of IBM PC, XT or AT, but a little shorter, and It was equipped with a raised stand on the upper surface of the case, designed to prevent the monitor from sliding sideways or backward. Both models had a built-in keyboard that tactilely and externally repeated the keyboard of the IBM Selectric typewriter , the most common office machine model of the time. The keyboard had amazing sensitivity and impact, according to which several issues went crazy for columnist Jerry Purnell, author of Byte magazine.
Specifications:
- Two processors : Intel 8085 and 8088
- The scope of delivery included the operating systems CP / M and Z-DOS (a non-IBM version compatible with MS-DOS .)
- 5 expansion slots on the S-100 bus
- Two 5.25- inch floppy drives for working with double-sided 40-track floppy disks with a capacity of 320 KB. There was also a connector that allowed you to directly connect an external 8-inch drive.
- 2 serial ports (on the 2661 UART chip ), 1 Centronics port for the printer (discrete TTL chips), port for the light pen .
- Monitor 640 by 225 pixels. 8-color (in the low-profile model) or monochrome with the ability to improve up to 8 shades of gray (all-in-one model).
- 128K RAM expandable up to 192K on the motherboard and up to 768K via S-100 cards. (Video memory above 768K was divided into 64K pages).
The Z-100 was partially compatible with the IBM PC using a standard floppy drive. He worked under the control of a non-IBM version of MS-DOS, so he allowed to run programs for MS-DOS. But most commercial software for personal computers used the IBM BIOS extensions and did not work. Several companies have offered software and hardware solutions to run unmodified programs for the IBM PC on the Z-100.
The Z-100 was superior in graphics capabilities to its modern CGA (monochrome raster 640 by 200 or 4-color 320 by 200), MDA (80 by 25 only text mode) and even Hercules (monochrome 720 by 348). Early versions of AutoCAD were released for the Z-100 due to its advanced graphics capabilities.
Parts manufacturers also released modifications to expand the memory on the motherboard and allowed the installation of the Intel 8087 mathematical coprocessor.
In 1983, Clarkson College of Technology (now the university, Clarkson University ) demanded that all freshmen buy the Z-100 as an entry requirement, making it one of the first institutions to oblige students to have their own computer.