# 066 - Use Your Scope!

- Show: [Unnamed Reverse Engineering Podcast](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast)
- Published: 2023-12-09
- Length: 1h 40m
- Episode: 66
- Page: https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope
- Listen: https://unnamedre.com/episode/66

## Summary

James Lewis, known as Bald Engineer, details his reverse engineering of the Apple II MegaII chip to build a functional computer, explaining how he used KiCad, JLCPCB, and RP2040 microcontrollers to recreate vintage hardware. He discusses the challenges of debugging with Digilent Digital Discovery and Analog Discovery 2 tools, noting that the MegaII was likely an incomplete chip repurposed for I/O in the Apple II GS. Lewis also shares technical insights on capacitor aging, oscilloscope safety, and the importance of using test equipment correctly to avoid misleading results from logic analyzers.

## Chapters

- [0:03](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=3) Introduction: James Lewis and the MegaII Project
- [4:58](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=298) History of the Apple II, IIe, and MegaII Chip
- [14:30](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=870) Reverse Engineering the MegaII Pinout and Function
- [26:24](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=1584) Prototyping with KiCad, JLCPCB, and RP2040
- [36:26](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=2186) Debugging with Digilent Digital and Analog Discovery
- [1:15:13](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=4513) Capacitor Aging, Voltage Ratings, and Measurement
- [1:23:18](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=4998) Oscilloscope Safety and Trigger Modes
- [1:31:28](https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope#t=5488) Favorite Tools: Blue Masking Tape and Hot Glue Gun

## Topics

- [PCB design & layout](https://hardwarepodcasts.com/topic/pcb-design)
- [Debugging & failure analysis](https://hardwarepodcasts.com/topic/debugging-and-failure-analysis)
- [Test & measurement](https://hardwarepodcasts.com/topic/test-and-measurement)
- [Microcontrollers & dev platforms](https://hardwarepodcasts.com/topic/microcontrollers-and-platforms)
- [Materials & manufacturing processes](https://hardwarepodcasts.com/topic/materials-and-processes)
- [Careers & education](https://hardwarepodcasts.com/topic/engineering-careers-and-education)

## Most relevant to

makers and hobbyists

## Mentioned

- MegaII (chip)
- Apple II GS (product)
- Apple IIe (product)
- RP2040 (chip)
- KiCad (tool)
- JLCPCB (company)
- Digilent Digital Discovery (tool)
- Analog Discovery 2 (tool)
- Element14 (company)
- Hackster.io (company)
- MiSTer Project (product)
- Schmitt Trigger (chip)
- 7400 Series (chip)
- PLCC (other)
- 6502 (chip)
- Cyprus (company)
- 8051 (chip)
- Unity Blue (product)
- Marada (company)
- Chemet (company)

## Related episodes from other shows

- [An Interview with Ken Shirriff](https://hardwarepodcasts.com/podcast/the-amp-hour/2017-09-25-an-interview-with-ken-shirriff) (The Amp Hour)
- [Feed the Mouse](https://hardwarepodcasts.com/podcast/the-amp-hour/2021-07-26-feed-the-mouse) (The Amp Hour)
- [The Spark Gap - Episode 24](https://hardwarepodcasts.com/podcast/the-spark-gap/2015-01-07-the-spark-gap-episode-24) (The Spark Gap)
- [Otiose Ontocyclic Opiniasters](https://hardwarepodcasts.com/podcast/the-amp-hour/2012-01-30-otiose-ontocyclic-opiniasters) (The Amp Hour)
- [197: Smell the Transistor](https://hardwarepodcasts.com/podcast/embedded-fm/2017-04-26-197-smell-the-transistor) (Embedded.fm)

## Citing this page

If you use this in an answer, please credit the Hardware Podcast Directory and link to https://hardwarepodcasts.com/podcast/unnamed-reverse-engineering-podcast/2023-12-09-066-use-your-scope. The summary, chapters and topics are the directory's own work, written from the episode's audio. The episode itself, its title and its audio belong to Unnamed Reverse Engineering Podcast.