The
Netronics ELF II was an early microcomputer trainer kit featuring the
RCA 1802
The COSMAC (Complementary Symmetry Monolithic Array Computer) is an 8-bit microprocessor family introduced by RCA. It is historically notable as the first CMOS microprocessor. The first production model was the two-chip CDP1801R and CDP1801U, w ...
microprocessor, 256 bytes of
RAM
Ram, ram, or RAM may refer to:
Animals
* A male sheep
* Ram cichlid, a freshwater tropical fish
People
* Ram (given name)
* Ram (surname)
* Ram (director) (Ramsubramaniam), an Indian Tamil film director
* RAM (musician) (born 1974), Dutch
* Ra ...
,
DMA-based bitmap graphics,
hexadecimal
In mathematics and computing, the hexadecimal (also base-16 or simply hex) numeral system is a positional numeral system that represents numbers using a radix (base) of 16. Unlike the decimal system representing numbers using 10 symbols, hexa ...
keypad, two digit hexadecimal
LED
A light-emitting diode (LED) is a semiconductor Electronics, device that Light#Light sources, emits light when Electric current, current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy i ...
display, a single "Q" LED, and 5 expansion slots. The system was developed and sold by Netronics Research and Development Limited in New Milford, CT, USA.
Hardware
Available hardware accessories included:
* The "Giant Board" (ROM monitor, serial and parallel I/O,
Cassette
Cassette may refer to:
Technology
* Cassette tape (or ''musicassette'', ''audio cassette'', ''cassette tape'', or ''tape''), a worldwide standard for analog audio recording and playback
** Cassette single (or "Cassingle"), a music single in the ...
interface)
* 4KB and 16KB (static) RAM boards
* Low resolution color graphics board
* "Full BASIC" board with
BASIC
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...
preloaded in
ROM
Rom, or ROM may refer to:
Biomechanics and medicine
* Risk of mortality, a medical classification to estimate the likelihood of death for a patient
* Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac
* R ...
chips
*
EPROM burner board
* External power supply
* Attractive, heavy duty metal cases for the CPU and power supply
Software
Available software included:
*
Tiny BASIC
Tiny BASIC is a family of dialects of the BASIC programming language that can fit into 4 or fewer KBs of memory. Tiny BASIC was designed in response to the open letter published by Bill Gates complaining about users pirating Altair BASIC, which ...
(
integer
An integer is the number zero (), a positive natural number (, , , etc.) or a negative integer with a minus sign (−1, −2, −3, etc.). The negative numbers are the additive inverses of the corresponding positive numbers. In the language ...
BASIC interpreter)
* Text Editor
* Full BASIC (
floating point
In computing, floating-point arithmetic (FP) is arithmetic that represents real numbers approximately, using an integer with a fixed precision, called the significand, scaled by an integer exponent of a fixed base. For example, 12.345 can be ...
BASIC
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...
interpreter using
Reverse Polish Notation
Reverse Polish notation (RPN), also known as reverse Łukasiewicz notation, Polish postfix notation or simply postfix notation, is a mathematical notation in which operators ''follow'' their operands, in contrast to Polish notation (PN), in whi ...
)
Notable Features
* Unlike similar "bare circuit card" trainer/experimenter computers of the day, the ELF II could be easily expanded thanks to its built-in bus.
* Memory mapped TV graphics was provided in the base kit by the
CDP1861 "Pixie-Graphics" chip. Pixels were large. With unexpanded 256 byte memory, the interrupt routine needed to service the chip showed on the screen.
* The "Full BASIC" ROM card provided an
RPN calculator chip as a simple and low-cost
math coprocessor
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
. As a result, floating point operations were an order of magnitude faster than what was possible in software. However, the BASIC syntax for math was non-standard as it used postfix RPN (see code example below). Historically, this was also the heyday of
Hewlett Packard
The Hewlett-Packard Company, commonly shortened to Hewlett-Packard ( ) or HP, was an American multinational information technology company headquartered in Palo Alto, California. HP developed and provided a wide variety of hardware components ...
calculators, so it was a fair bet that any technically minded person willing to assemble a computer either already knew RPN or could easily learn it and adapt.
10 REM This program will print the number 30
20 A=10,B=20
30 C=A#B+
40 PRINT C
50 END
In the code above, the "#" symbol is equivalent to the "Enter" key on a RPN calculator.
Netronics Video Terminal
Netronics also offered:
* An ASCII keyboard kit
* Heavy duty metal keyboard case
* Video terminal card kit (monochrome text, 16 lines by 64 characters, upper & lower case)
The keyboard could be used alone to generate ASCII parallel codes. The video terminal card fit underneath the keyboard in the optional case to form a stand-alone video terminal sending and receiving serial ASCII. Either configuration could be interfaced to the ELF II through the Giant Board. The terminal kits were also marketed independently of the ELF II.
The Name
The ELF part of the name came from an earlier machine called the "
COSMAC ELF", published as a construction project in
Popular Electronics
''Popular Electronics'' was an American magazine published by John August Media, LLC, and hosted at TechnicaCuriosa.com. The magazine was started by Ziff-Davis Publishing Company in October 1954 for electronics hobbyists and experimenters. It soo ...
magazine. Improvements on its predecessor included an etched
PCB
PCB may refer to:
Science and technology
* Polychlorinated biphenyl, an organic chlorine compound, now recognized as an environmental toxin and classified as a persistent organic pollutant
* Printed circuit board, a board used in electronics
* ...
, a hexadecimal keypad instead of toggle switches for program entry, the
RCA CDP1861
The RCA CDP1861 was an integrated circuit Video Display Controller, released by the Radio Corporation of America (RCA) in the mid-1970s as a support chip for the RCA 1802 microprocessor. The chip cost in 1977 amounted to less than US$20.
History
T ...
Pixie-graphics chip, and the 5 slot 86-line bus for expansion cards.
See also
*
COSMAC ELF
*RCA
COSMAC VIP
The COSMAC VIP (1977) IP means Video Interface Processorwas an early microcomputer that was aimed at video games. Essentially, it was a COSMAC ELF with a supplementary CDP1861/CDP1864 video display chip. For a price of US$275, it could be purc ...
*
Quest SuperELF
*
RCA 1802
The COSMAC (Complementary Symmetry Monolithic Array Computer) is an 8-bit microprocessor family introduced by RCA. It is historically notable as the first CMOS microprocessor. The first production model was the two-chip CDP1801R and CDP1801U, w ...
microprocessor
*
Early Microcomputers
Early may refer to:
History
* The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.:
** Early Christianity
** Early modern Europe
Places in the United States
* Early, Iowa
* Early, Texas
* Early ...
*Competing 6502 microprocessor based trainers
KIM-1
The KIM-1, short for ''Keyboard Input Monitor'', is a small 6502-based single-board computer developed and produced by MOS Technology, Inc. and launched in 1976. It was very successful in that period, due to its low price (thanks to the inexpe ...
and Rockwell
AIM-65
The Rockwell AIM-65 computer is a development computer introduced in 1978 based on the MOS Technology 6502 microprocessor. The AIM-65 is essentially an expanded KIM-1 computer. Available software included a line-oriented machine code monitor, ...
*8080 Based machines: MITS
Altair 8800
The Altair 8800 is a microcomputer designed in 1974 by MITS and based on the Intel 8080 CPU. Interest grew quickly after it was featured on the cover of the January 1975 issue of Popular Electronics and was sold by mail order through advertiseme ...
and
IMSAI 8080
The IMSAI 8080 was an early microcomputer released in late 1975, based on the Intel 8080 and later 8085 and S-100 bus. It was a clone of its main competitor, the earlier MITS Altair 8800. The IMSAI is largely regarded as the first "clone" micr ...
*
RCA Studio II
The RCA Studio II is a home video game console made by RCA that debuted in January 1977. The graphics of Studio II games were black and white and resembled those of earlier Pong consoles and their clones. The Studio II also did not have joysticks ...
References
External links
* {{cite web
, url = http://www.cosmacelf.com/links.htm
, title = COSMAC ELF
Early microcomputers