Micro-Elf
Posted by musovern on May 19th, 2019 in Cosmac-Elf, Single Board Computers | 1 comment
This is based on the Micro- Elf project presented in Popular Electronics. Mike Riley from Elf-emulation.com has designed a PCB to make for easier construction than the wire-wrap method used in my Cosmac Elf.
Read More...The Cosmac “Elf”
Posted by musovern on Apr 24th, 2018 in Cosmac-Elf, Single Board Computers | 0 comments
In August 1976 issue of Popular Electronics magazine, Joseph Weisbecker published a design for “Low-cost experimenter’s microcomputer” using RCA’s COSMAC CDP1802 microprocessor chip. It is a very simple computer having 256 bytes of memory, switches as input and LED as output. No ROM, every time you turn it on you have to enter program to RAM by toggling 8 switches, one for each bit. After the switches are set, pressing IN-button stores that byte to memory and increments address. Remember, that it only had 256 bytes of RAM, so it was not that big deal, but still takes some time. There is no way to step address backwards – if you made a mistake you have to start from beginning.
Read More...Super Elf
Posted by musovern on Apr 15th, 2018 in Cosmac-Elf, Single Board Computers | 0 comments
The SuperElf single-board computer was made by Quest Electronics. It was an improvement of the Netronics Elf and Elf II training boards, also based on the RCA 1802, one of the first RISC microprocessors.
The board also featured an 1861 video chip that was closely tied to the 1802 to generate a video image of 128×64 dots.
2, 4 or 6 7-segment Led display could be used. Its hexadecimal keyboard allowed programs to be entered and controlled more efficiently thanks to 8 function keys:
Read More...Pico/ELF
Posted by musovern on Apr 10th, 2018 in Cosmac-Elf, Single Board Computers | 0 comments
The Pico/Elf is a Micro/Elf derivative. By eliminating the displays and switches (as well as associated circuitry), Mike Riley has been able to add the IDE, Serial port, and Eprom socket. Circuitry has been added to allow the computer to boot from rom by swapping 32k banks until the upper 32k is accessed. This machine also includes the Version 2 Micro/Elf expansion connector. This is an excellent small comptuer for running Elf/OS.
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