Show Notes
Why put a microcontroller in the trunk instead of simply tapping into the brake lights or turn signals?
In this episode of Shop Talk, Dave and Glen dig into the hidden trade-offs behind Dave’s Mark III RGB lighting project: reading outputs instead of inputs, handling hazard lights and reverse lights, burned-out bulbs, unexpected states, wiring, waterproofing, optocouplers, LEDs, ESP32s, schematics, Gerber files, and the difference between a quick solution and a robust one.
They also follow up on software optimization, AI-assisted programming, assembly-level code, compilers, C variable arguments, and whether modern hardware prices might finally make optimization matter again.
Plus: CAN bus projects, Knight Rider lights, a PDP-11 controller, time machines, Bunnyhugs, and other important engineering questions.
Questions from viewers on Dave’s Garage and Shop Talk.
00:00 - Hey I’m Dave… 00:34 - Why put the controller in the trunk? 03:05 - Why not just tap the brake and flasher circuits? 03:51 - Why avoid CAN and LIN bus projects? 05:36 - How does it handle burned-out bulbs? 06:52 - What happens with four-way flashers? 07:30 - Hazards and rapid turn-signal changes 08:07 - Hazards, reverse lights, and braking 09:21 - How does the strip behave in hazard mode? 10:21 - What happens if the controller reboots mid-drive? 11:09 - Will water collect behind the LED strip? 12:03 - Which LEDs did you use, and how are they mounted? 13:19 - How do the optocouplers protect factory wiring? 13:59 - Which LED strip and ESP32 should builders use? 15:34 - Can you share the schematic? 15:55 - How did you make the LED-system diagram? 16:23 - Are there certification rules for vehicle lighting? 18:33 - How did you route the wiring to the strip? 19:16 - Will you release the PCB design files? 19:56 - Will the controller board be available to buy? 20:45 - When does production start? 21:16 - Can AI optimize code at the assembly level? 21:53 - Did BBT support position-independent code? 23:01 - Do programmers use optional stops like CNC? 23:41 - Is programming becoming an AI-assisted profession? 24:29 - When did Microsoft start optimizing software? 25:52 - How are C variable arguments parsed? 26:37 - Why did programming languages become more human-readable? 28:22 - What is LNC 460? 28:42 - Why not use a PDP-11 as the controller? 29:40 - Why are rebuilt carburetors worse now? 30:40 - Why is there a case of oil in the trunk? 31:11 - Did this car come from an Alabama auction? 31:26 - How does the car handle unleaded fuel and synthetic oil? 32:16 - Why not add a Knight Rider light effect? 32:33 - Is “turn signaling” a Canadian thing? 32:53 - Could the emergency mode be triggered remotely? 33:24 - Why is the high-mounted brake light so low? 33:40 - Could brake-light brightness reflect braking force? 35:10 - Why not add an orange warning mode? 35:34 - Can Dave’s Garage make a Bunnyhug? 37:30 - End of show shenanigans 42:23 - The Friendly Coder…
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