Classic, vintage, or retro computer systems are well documented on sites like Wikipedia. Their historic position is well known. Their schematics are even published from original documentation. But how useful are those schematics in their current form? (Spoiler, not much.) Presented at KiCon 2019.

1. 1
Preserving History
with KiCad

2. 2
Portable Apple II
Use the minimum number of chips necessary for a
portable Apple II to run games.
(Okay, Oregon Trail.)
Original Apple II used 88 chips

3. 3

4. 5
The Trinity
The most popular computers for almost a decade.
T R S - 8 0
Radio Shack / Tandy
A p p l e I I
Apple Computer
C o m m o d o r e 6 4
CBM
Credit: Wikimedia Commons, Various

5. 6

6. 7
7
C64 User Manual and Schematic
Source: c64-wiki.com

7. 11
Apple II CPU
RAM
ROM

8. 12
Apple IIe
RAM
ROM
ROM
ROM
ROM
CPU
MMU
IOU
KBD
PAL

9. 13
Apple IIc Logic Board
IWM

10. 14
Apple IIgs
1 6 -B it / 8 MB RAM / 4 0 9 6 Co lo rs
Apple II Backward Compatibility

11. 15
© Stephan Slabihoud, Scan by Wayne Stewart, 8bit-museum.de
MEGA
IIVGC
FPI
CPU
ROM
PLA
IWM
SLOT
MAKER
SOUNDKBD
PLA
RAM
RAM
RAM
SCC

12. 16

13. 17
Mega-II
6502 RAM ROMVGC
IWM
Keyboard TFT Gamepad

14. 18
Why Bother?
Aren’t PDFs
Good Enough?

15. 19
Platform
Requirements
✔ Platform
✔ Open File Format
✔ Long Term Support
✔ Accessible
✔ Scripting
✔ Autorouter

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Cross Platform

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Open file format
????
KiCad EAGLE Altium

18. 22
Long Term Support
Introduction Growth Maturity Decline

19. 23
Accessibility
Are others open and willing to collaborate on the platform
C o s t U s a b i l i t y C a p a b i l i t y

20. 24
Scripting
<
ULP Python

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Autorouter

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KiCad is Best Option

23. 27
L ive Stre am
twitch.tv/baldEngineer
youtube.com/AddOhms

24. 28
Apple ASIC Symbol Library

25. 29
Multi schematic page

26. 30
Example schematic sheets

27. 31
Not all Pin
35s are
created
equal

28. 32
Long Wire Pin Labels
Useful for PDF or static schematics since there is
limited search capability. However, it means a lot of
manual tracing.
Cleaner schematic and easier to do automated search.
Potential for typos.

29. 33
How to automate
creating decoupling
capacitor arrays?
(Reverse) SKIDL?

30. 34
Visit GitHub Repository
34

31. 35
Visit GitHub Repository #2
35

32. 36
Visit GitHub Repository #3
36

33. 37
Collaboration
Publish Final
Verify with Hardware
Validate Capture
Submit Rev
Initial Capture
Pick a system
github.com/baldengineer/bit-preserve

34. 38
Contact Me
james@baldengineer.com
email | www | twitter
github.com/baldengineer/bit-preserve