Video of YACC 2020 monitor program and BASIC interpreter.
Sometimes you just need to get out the soldering iron and build something. Fortunately I had an Altairduino kit waiting to be built. Nice kit and easy to follow instructions. Couple of small changes to the build instructions. In order to get a nice fitting front panel I chose not to install the top panel first. To do this I held the nuts required to secure the front panel in with tape (see image).
Yacc1 will be a multi-board system requiring a motherboard, really more of a basic bus-board, for cards to plug into. For my previous 1802 projects single row breakaway headers with a simple bus-board made of either Veroboard or a simple PCB had all the pins, a grand total of 3X, required.
This custom cpu project will require far more interconnects so I ended up selecting DIN 41612 3 x 32 connectors. They physically strong and will withstand the repeated insertions and removals while at the same time quite cost effective
Spare Time Gizmos’ EELF
With the UART/IDE/RTC card/
Custom CPU Projects
Misery loves company.
A partial list of custom CPU projects, specifically interested in TTL based projects. Omitted are projects using relays, transistors only, and FPGAs.
A Minimal TTL Processor for Architecture Exploration
Galactic Electronics 4 bit machine
TTL COMPUTER BY ALESSIO LOMBARDO
* 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.
1802 Project Index
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.
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)
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
Cathode (flat section) facing inward toward bus connector
5.2 (X axis) by
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
Bypass capacitors C025-050×050
Tantalum capacitor placement .45 x 3.45 (+) closer to VCC
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
Do ERC Check
Verify GND and VCC Connected at bus
Verify unconnected input pins on pin list
Run CAM JOBS
!!!Update file names and order number inside readme file before uploading zip file for production!!!