The COSMAC “ELF” was a microcomputer design by Joseph Weisbecker that was announced in the pages of the August edition of Popular Electronics . This is an implementation of the COSMAC Elf, constructed in going by the issues of Popular Electronics, with additional articles in March and July Popular Electronics was famous for the article introducing the Altair ran on building a very simple computer called the COSMAC ELF.

Author: Shaktiktilar Kajik
Country: Malawi
Language: English (Spanish)
Genre: Spiritual
Published (Last): 5 September 2005
Pages: 300
PDF File Size: 18.93 Mb
ePub File Size: 2.65 Mb
ISBN: 765-1-93475-313-2
Downloads: 25457
Price: Free* [*Free Regsitration Required]
Uploader: Tulrajas

If you don’t have anthe Elf has space and standoffs to mount a daughter board that plugs into the socket and contains a discrete logic replacement for the You might want to check out the Z based P or, if you want to go all the way, the Stack If you don’t like toggle switches, the Elf can also accommodate a Super Elf style hex keypad and push button controls.


Vintage COSMAC Elf is Pretty Close to Original

When processing data in memory, you typically only need 2 registers source and destination. As I recall the software development team was about 8 programmers. Popu,ar finally, we can sell you a complete kit of all the parts needed to build an Elfbut notice that this kit doesn’t include the switches or switch panel.

Views Read Edit View history. Also, prices have dropped enough that you can try two or three if you choose. For example, on reset, R0 one of those 16 sixteen bit registers was the default program counter, but also the DMA register, and it was reset to h. Perhaps you would like to see my rebuild of the original ELF?

Vintage COSMAC Elf is Pretty Close to Original | Hackaday

As in film photography? It is compleletly static, meaning that its clock can be stopped without loosing the internal states reducing power consumption.


Eelectronics should eletronics said that the did advance to the processor which improved the instruction set.

How many of you remember the Altair ?? Clearly remember buying the IC sockets exactly doubled the price of the project. Is the author willing to share his Front Panel Express files, so we can replicate his nice-looking switch panel? I will probably build an Elf clone also. ACE then started selling cassettes loaded with an poopular of the Forth language as published by the Forth Interest Group. Unfortunately, by the was hardly cutting-edge technology, and the slow speed of the machine quickly sealed its fate.

Email required Address never made public. It might be hard to understand why people got excited over a little computer with a handful of switches.

The is very simple to interface from a hardware point of view and has a very easy to learn machine language — a very small, very regular instruction set.

He even did a nice front panel using Front Panel Express. In short — probably a fantastic microcontroller for the day, but the and most other 8 bit chips were better general purpose devices.

A simple circuit used the DMA feature of the to permit entry of programs and data into RAM through the toggle switches. Software was typically published as a hexadecimal dump, often hand-typed, since relatively few members were working cosmaf the luxury of an assembler or printer.

Monochrome video output with cosmc roughly approximating NTSC standard could be generated using DMA operations interleaved with carefully arranged opcodes as instructions in software.

Popular Electronics was famous for the article introducing the Altair back in well, the cover date was ; it elcetronics came out in late The cheap plastic version were not radiation hardened at all although it was the same chip.

You are commenting using your WordPress. The classic Elf “load” mode, of course, requires a genuine chip.


CHIP-8 was popular on thebut was not exclusive to it. Retrieved 19 August Free counters provided by Andale. The bad news about the Elf was that you had to toggle in programs using the eight front panel switches!

The DMA onboard the chip made the front panel simple, and it facilitated a companion graphics chip that produced crude black and white graphics on a monitor or TV.

One of the nice things about this processor is the multiple clocks required to complete each instruction. I have the Membership Card.

Build The COSMAC “ELF” Part 1

Want to call a subroutine? I want to just say that the 16 bit registers in the are not majorly used for memory data pointers. While the has a lot more cool features, it lacks some of the advanced programming abilities that the has. Popupar people bought more than one Elf and some one might be willing to sell theirs. The original ELF project featured: Consider the Altair, though.

Software development was done in assembly language pouplar a cross assembler which was written in-house and ran on Computer Automation Alpha LSI minicomputers.

File dumps of these games can be found on the Internet. Armed with a common bus, ACE began to design, publish and sell their own circuit boards. The instructions are very simple, and in fact, this processor is considered a RISC. If an error was made in program entry, it could be corrected by turning on memory protect, turning off load mode thus resetting the program counter to zeroturning on load mode, and pressing “input” to advance to the address of the incorrect data.