IBM 2260
| Company type | Product |
|---|---|
| Industry | Computer hardware |
| Founded | 1964 |
| Products | Monochrome CRT video display terminals (Models 1, 2, and 3) |
The IBM 2260 was a monochrome cathode-ray tube (CRT) video display terminal equipped with a keyboard, launched in 1964 as an early model preceding the more sophisticated IBM 3270 series, which eventually incorporated color text and graphics capabilities. This terminal came in three variants: Model 1 presented 240 characters arranged in six rows of forty; Model 2 offered 480 characters across twelve rows of forty; and Model 3 delivered 960 characters spread over twelve rows of eighty, aligning with the width of IBM punch cards. Additionally, a version without a keyboard, intended solely for display purposes, was available. The IBM 2260 and its later models played a significant role in shifting from punch-card systems to CRT-based computing, contributing to the foundational ideas behind the paperless office.
Distinctively, the 2260 utilized a raster display featuring vertical scan lines that moved from top to bottom—a design not commonly seen at the time. As many as twenty-four IBM 2260 terminals could be linked to an IBM 2848 Display Control unit, which functioned either as a channel-attached local device or remotely, supporting data transmission speeds up to 2400 bits per second. An optional interface enabled sharing a single IBM 1053 printer among all connected terminals.
To store screen data, the IBM 2848 employed an acoustic delay line memory system—a mechanical spiral wire coupled with an electromagnet and torsion detector—chosen due to the prohibitive expense of magnetic core memory for terminal use. This electromechanical feedback mechanism translated mechanical vibrations into raster scan lines for the CRT displays. However, vibrations caused by nearby activities such as heavy foot traffic or elevator operation could interfere with data flow, resulting in loss of screen images and repeated refresh cycles until new information was received.
The IBM 2265, aimed at individual terminal users, connected to an IBM 2845 controller and provided a more economical option compared to the IBM 2260 paired with the 2848 controller.
Both the IBM 2260/2265 terminals and the IBM 2848 controller implemented the authorized yet unpublished revision of the ASCII standard from 1965 (ASA X3.4-1965), demonstrating their early integration of evolving character encoding protocols.
External links
- "IBM System/360 Component Description: IBM 2260 Display Station IBM 2848 Display Control"
- "IBM System/36D Component Description: IBM 2265 Display Station Modell IBM 2845 Display Control"
- "The IBM 2260 Display Station" by Frank da Cruz, 2021, Columbia University Computing History