Tektronix 4014
Encyclopedia
Tektronix
Tektronix, Inc. is an American company best known for its test and measurement equipment such as oscilloscopes, logic analyzers, and video and mobile test protocol equipment. In November 2007, Tektronix became a subsidiary of Danaher Corporation....
4000 series was a family of text and graphics computer terminal
Computer terminal
A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system...
s based on the company's storage tube
Storage tube
Mostly obsolete, a storage tube is a special monochromatic CRT whose screen has a kind of 'memory' : when a portion of the screen is illuminated by the CRT's electron gun, it stays lit until a screen erase command is given...
technology. No additional electronics were needed to maintain the display, so the 4000 series were less expensive than earlier graphics terminals and became widely used in the CAD market in the 1970s and 80s. They remained popular until the introduction of inexpensive graphics workstations in the 1980s, which used raster displays and inexpensive screen buffer
Screen buffer
In computing, screen buffer is a part of computer memory used by a computer application for the representation of the content to be shown on the computer display....
s in place of custom hardware. There were several members of the family introduced through the 1970s, the best known being the 4010, 4014, 4100 and 4200.
Graphics display
Prior to the 4010 released in 1972, most computer graphicsComputer graphics
Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....
was done with vector graphics
Vector graphics
Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon, which are all based on mathematical expressions, to represent images in computer graphics...
displays that continuously repainted the image under computer control. This required a very high bandwidth connection to the computer, which generally meant the display could be no more than a dozen or so meters from the computer. The modern approach of having a local memory in the display that stores a value for each pixel
Pixel
In digital imaging, a pixel, or pel, is a single point in a raster image, or the smallest addressable screen element in a display device; it is the smallest unit of picture that can be represented or controlled....
would have been prohibitively expensive in the 1970s. Tektronix solved this problem by developing the Direct View Bistable Storage Tube (DVBST
DVBST
Direct-View Bistable Storage Tubes was an acronym used by Tektronix to describe their line of storage tubes. These were cathode ray tubes that stored information written to them using an analog technique inherent in the CRT and based upon the secondary emission of electrons from the phosphor...
) CRT
Cathode ray tube
The cathode ray tube is a vacuum tube containing an electron gun and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam onto the fluorescent screen to create the images. The image may represent electrical waveforms , pictures , radar targets and...
, which allowed the use of a slower serial
Serial communications
In telecommunication and computer science, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels...
data connection combined with a vector graphics generator that only needed to write the vectors (the graphic data) to the CRT once. Having had data written, the CRT itself remembered the data. Individual portions of the image could not be erased, however. Instead, the entire stored image was erased as a whole and the process caused the entire screen to flash bright green.
Graphics input
For graphics input, the terminal used a pair of thumb wheels on the keyboard to control the position of a cursorCursor (computers)
In computing, a cursor is an indicator used to show the position on a computer monitor or other display device that will respond to input from a text input or pointing device. The flashing text cursor may be referred to as a caret in some cases...
. The cursor was displayed using a lower intensity of the electron beam that was insufficient to store the cursor's image. Instead, the cursor was dynamically refreshed by the electronics of the terminal.
Commands
The 4014 had a series of commands for drawing both text and graphics. The 4014 command set became a de factoDe facto
De facto is a Latin expression that means "concerning fact." In law, it often means "in practice but not necessarily ordained by law" or "in practice or actuality, but not officially established." It is commonly used in contrast to de jure when referring to matters of law, governance, or...
standard and when personal computers with graphics displays became common in the 1990s, many communications packages included the ability to accept Tektronix 4014 commands. Because of this the designation "(Tektronix) 4014" has entered the traditional computing vocabulary, leading to the memory of the terminal long after the actual hardware became obsolete and otherwise disappeared.
History
The Tektronix direct-view storage tube was first used in the Tektronix 564 oscilloscopeOscilloscope
An oscilloscope is a type of electronic test instrument that allows observation of constantly varying signal voltages, usually as a two-dimensional graph of one or more electrical potential differences using the vertical or 'Y' axis, plotted as a function of time,...
in 1963 and was first used for non-oscilloscope applications in the 601 monitor in 1968.
Another early device was called ARDS for Advanced Remote Display Station and originated at MIT
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...
's Project MAC. In addition, Digital Equipment Corporation
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
of Maynard
Maynard, Massachusetts
Maynard is a town in Middlesex County, Massachusetts, United States. As of the 2010 census, the town population was 10,106.- History :Maynard, located on the Assabet River, was incorporated as an independent municipality in 1871. Prior to that it was known as 'Assabet Village' but was legally...
, Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
sold a graphics system called the KV8I (later, KV8E) that used a Tektronix 603 storage display as its output device with the KV8I generating the vectors.
The first Tektronix computer terminal to use a storage tube was the T4002 Terminal, and the first member of the 4010 Series was the 4010, introduced around 1972. Other models included the 4012 (added lower case to the 4010 hardware character set), 4014 (four times the 4010 screen area), 4105, and 4016-1. Several peripherals were available, including the 4631 Hard Copy Unit, which produced screenshot
Screenshot
A screenshot , screen capture , screen dump, screengrab , or print screen is an image taken by a computer to record the visible items displayed on the monitor, television, or another visual output device...
s on dry silver paper that were then heat-developed in the printer.
xterm
Xterm
In computing, xterm is the standard terminal emulator for the X Window System. A user can have many different invocations of xterm running at once on the same display, each of which provides independent input/output for the process running in it .xterm originated prior to the X Window System...
still emulates the 4014 (xterm -t), as well as the VT220
VT220
The VT220 was a terminal produced by Digital Equipment Corporation from 1983 to 1987.-Hardware:The VT220 improved on the earlier VT100 series of terminals with a redesigned keyboard, much smaller physical packaging, and a much faster microprocessor...
.
4010 Technical data
| Construction: | Pedestal with keyboard Keyboard (computing) In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches... |
| Display: | 74 × 35 characters or 1024 × 780 pixels. |
| Screen size: | 6.7 by 9 in (17 by 22.9 ) |
| Character set: | 64 printing characters including space Whitespace (computer science) In computer science, whitespace is any single character or series of characters that represents horizontal or vertical space in typography. When rendered, a whitespace character does not correspond to a visual mark, but typically does occupy an area on a page... |
| Keys: | 52 typewriter keys + cross-hair controls Graphics tablet A graphics tablet is a computer input device that enables a user to hand-draw images and graphics, similar to the way a person draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures... and switches |
| Auxiliary keypad: | None |
| Visual indicators: | Power lamp + Two indicator lamps |
| Operating modes: | Alphanumeric Alphanumeric Alphanumeric is a combination of alphabetic and numeric characters, and is used to describe the collection of Latin letters and Arabic digits or a text constructed from this collection. There are either 36 or 62 alphanumeric characters. The alphanumeric character set consists of the numbers 0 to... , Graphic plot, Graphic input, Print |
| Interface: | RS-232C/V.24 RS-232 In telecommunications, RS-232 is the traditional name for a series of standards for serial binary single-ended data and control signals connecting between a DTE and a DCE . It is commonly used in computer serial ports... , Teletype Teleprinter A teleprinter is a electromechanical typewriter that can be used to communicate typed messages from point to point and point to multipoint over a variety of communication channels that range from a simple electrical connection, such as a pair of wires, to the use of radio and microwave as the... |
| Flow control Flow control In data communications, flow control is the process of managing the pacing of data transmission between two nodes to prevent a fast sender from outrunning a slow receiver. It provides a mechanism for the receiver to control the transmission speed, so that the receiving node is not overwhelmed with... : |
None |
| Communication Speeds: | 110, 300, 600, 1200, 2400, 4800, 9600 bit/s |
| Dimensions: | 35.25 by 18.25 in (89.5 by 46.4 ) × 28.5 inches (72.4 cm) |
| Weight: | 80 pounds (36.3 kg) |
To make it work as a RS-232C at 2400 bit/s, no-parity, 8-bits, 1 stop-bit. Set the T Data strap to Normal. R Data strap to Invert. Baud Shift to On, and adjusted the trimmer by TP1 to give a clock frequency of about 19 kHz, measured at TP1.