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 through D7 to the appropriate +5V and GND signals and connected an LED and resistor to the Q signal. Using wires connected to the control lines I reset the CPU and then set it to run. I pulsed the clock line with a de-bounced switch and after 21 pulses the LED connected to the Q line lit up. From that moment on I was hooked. Comments to Ken

Front Panel from System-1, every real computer has a front panel.

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 card supports

LED Placement

Cathode (flat section) facing inward toward bus connector

5.2 (X axis) by

(y -axis)

0.3 Power – Label PWR 5.4 x .45

1.0 Aux 1 – Label xxx 5.4 x xxx

1.7 Aux 2

2.4 Aux 3

3.1 Aux 4

Eagle Library components

LED type 5MM

Resistors 207/7

Bypass capacitors C025-050×050

Tantalum capacitor placement .45 x 3.45 (+) closer to VCC

Board Labeling

NAME Label .05 x .05

FORMAT: KSR – XXX#-A

XXX = Board name

# = board design (different types of similar function)

A = Revision level

All slik screen writing on layer 25

PC Board Silk Screen uses layers 20, 21, 25

Verify Process

Do ERC Check

Verify GND and VCC Connected at bus

Verify unconnected input pins on pin list

Build Process

Run CAM JOBS

gerb274x.cam

excellon.com

Run Script

“doc”

!!!Update file names and order number inside readme file before uploading zip file for production!!!

System 5 – Screen Shots

OLYMPUS DIGITAL CAMERA

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 KSR

Source: bios.asm

Include: bios.inc

Makefile: Makefile


Changes required to Mike Riley’s BIOS (version 1.0.4)

Source: bios.asm

Include: bios.inc

Makefile: Makefile

Note: Makefiles require srecord utility – see the Tools Directory

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 mode inputs, and a switch for input during load mode

Issues/todo log

Date Description Status

Schematics, board layout, and operational description

Revision Production Date Schematic Layout Operational Description

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
A Under Development proto1-a.sch proto1-a.brd Rev. A ops notes

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 addition of some jumper blocks to select I/O ports. This is required to support compatibility of some older software of my own that used the original ports.

Issues/todo log

Date Description Status

Schematics, board layout, and operational description

Revision Production Date Schematic Layout Operational Description
A Feb. 11/2005 ide1-a.sch

ide-a.brd