Spare Time Gizmos’ EELF With the UART/IDE/RTC card/
1802 projects
A long time favorite of mine, posts on many of my RCA 1802 projects
1802 World
1802 World * System-5 for Running ELF/OS * Click the image to take a look My first brush with the 1802 was late 1977, like so many others the series of articles in Popular Electronics got me hooked. My first project was on a solderlss breadboard I wired 0x7B onto the data bus by directly connecting D0 […]
1802 Project Index
Tools
Srecord-1.20 is a very useful tool for manipulating various ASCII/HEX/BINARY files for creating EPROM images check http://srecord.sourceforge.net/ for the latest information. Source: srecord-1.20.tar.gz Documentation: srecord-1.20.pdf Source: srecord-1.23.tar.gz Documentation: srecord-1.23.pdf RCASM is the assembler needed by several of the Makefiles to build the BIOS Source Zip File: rcasm.tgz
Board Construction Notes
Last Updated Mar. 08/2005 Board size 5.50 x 3.75 Bus Connector placement Center location 0.2 x 1.875 (set Eagle grid to 0.025 to place connector and then restore to 0.05) Restricted areas Layer 41 and 42 place 3.00 x 0.15 polygons left and right bottom corners (next to bus connector) to prevent traces from contacting […]
System 5 – Screen Shots

Last Updated: November 09, 2005 09:48:34 PM http://cottageworker.com/wp-content/uploads/2014/05/ The ELF/OS install menu, jumped to from the monitor section of the BIOS. BTW: the current video system only supports upper case characters. http://cottageworker.com/wp-content/uploads/2014/05/ A running ELF/OS! http://cottageworker.com/wp-content/uploads/2014/05/ A successful DIR command.
BIOS
System-5 HBIOS (Hardware BIOS) This code handles the video and keyboard I/O required by Mike’s BIOS (see below). Startup jumps to minimon section of BIOS. Source: sec1.asm Makefile: Makefile (assumes Mike’s BIOS is in subdirectory called orig_bios) Changes required to Mike Riley’s BIOS (version 0.9) Changes to BIOS are marked with conditional compilation using #DEFINE […]
Front Panel Card
Last Updated: November 09, 2005 09:48:34 PM UNDER CONSTRUCTION No version of this card exists yet Description The Front panel will uses TIL311 displays for address and Data, a sinlge LED for Q, 4 LEDS for mode (run,reset,load,wait). 8 switches for data input, 1 switch connected to an EF line, 4 push buttons connected to […]
Solderless Breadboard Prototyping Card: Revision A
Last Updated: November 09, 2005 09:48:34 PM UNDER Development No PCB has been produced yet Description The Solderless breadboard provides a platform for developing new circuits for SYSTEM-5. Issues/todo log Date Description Status Mar. 8/2005 Add decode logic for input and output Schematics, board layout, and operational description Revision Production Date Schematic Layout Operational Description […]
IDE Interface Card: Revision A
Last Updated: November 09, 2005 09:48:33 PM http://cottageworker.com/wp-content/uploads/2014/05/ Rev. A of the IDE Interface card populated with a CF to IDE interface and 16MB CF card. Jumpers select the I/O ports for IDE control and data read/write. Description This design is borrowed directly from Mike Riley’s 8 bit IDE Interface. The only change is the […]