SOUND & LIGHT PROTOCOL

MISSION BRIEFING

For this week's objective: create a pcb board that integrates LEDs and a push button, all controlled by a XIAO RP2040.

01. THE ARSENAL

To complete this mission, I gathered the following components from the Fab Lab inventory:

• Seeed Studio XIAO RP2040 (The Brain)
• Push button With a pull-up resistor
• LEDs 1206 SMD (Visual feedback)
• Resistors 1206 SMD (Current limiting for the LEDs)
• Pin Headers (For connections)

02. THE BLUEPRINT (KICAD DESIGN & EXPORT)

To kick off the blueprinting phase, I recycled the exact same schematic design from Week 06. Since the logic was already perfectly established and verified, I just forged ahead into the PCB editor, routing the traces with a safer 0.8mm width.

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01. Repurposing the mission schematic from Week 06 for the sound protocol.

02. Routing the copper traces with a safer 0.8mm width.

EXPORTING TO GERBER

To ensure the smoothest communication with the milling machine, I exported the layout layers as Gerber files instead of SVG, and then converted them into high-resolution PNGs using a specialized Fab Lab web tool.

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01. Setting up the Plot window to export F.Cu and Edge.Cuts as Gerber files.

02. Converting the mathematical Gerber data into high-contrast PNG images.

03. GENERATING TOOLPATHS (MODS)

Instead of capturing static screenshots, I recorded my entire workflow inside Mods platform and also I changed the "Gerber" files to png with gerber2png.fablabkerala.in. Here, I uploaded the PNG files, set the proper endmill settings (1/64 for traces, 1/32 for the outline), and calculated the precise `rml` toolpaths required by the Roland SRM-20.

04. MACHINE SETUP & VPANEL

Before any cutting could begin, the physical space had to be prepped. I secured the bronze board to the sacrificial layer using strong double-sided tape to prevent any disastrous movements during milling. I also equipped the machine with their proper screws.

01. Securing the board with double-sided tape.

02. Prepping the 1/64 and 1/32 endmills.

VPANEL CALIBRATION

Using the VPanel software, I carefully set the X, Y, and Z origins.

⚠️ CRITICAL WARNING: Once you hit the "Output" button to load your file, the machine will immediately begin to move and cut! Keep your hands out of the enclosure.

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01. Setting the origins on the Roland VPanel.

02. Loading the .rml toolpath file into the spooler.

03. The point of no return: hitting OUTPUT.

05. THE MILLING ACTION

With all parameters verified and the enclosure closed, the MonoFab SRM-20 went to work. Here is the physical fabrication process captured on video.

06. THE FINAL BOARD & HERO TESTS

The dust settled, and the board emerged. Clean cuts, perfectly isolated traces, and the custom shape of the Puebla shield perfectly executed. After the machining, the soldering phase was completed, bringing the circuit to life.

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01. The unpopulated, freshly milled PCB ready for the soldering iron.

02. The populated board with the XIAO RP2040, LEDs, and push button fully soldered.

HERO TESTING PROTOCOL

To verify the integrity of the circuit and the logic, the board underwent rigorous physical testing.

07. CLASSIFIED FILES

PRODUCTION COMPLETE

The board has been designed, milled, populated, and successfully tested. Mission accomplished.