Imported from GitHub: 0101shift/Project_OAK · commit 9e24250 · license MIT

Description

All design files, source code, and documentation for Project OAK, a digital watch inspired by mechanical complications.

README

🔧 Project OAK MAIN BRD V0.1 Rework

This document outlines the necessary fixes, design limitations, and manual rework instructions for Version 0.1 of the main board.

📋 Includes:

• Design errors identified during testing
• Workarounds and hardware patches
• Recommended changes for future revisions

⚠️ These instructions are critical if you're testing or building with Project_OAK_MAIN_BRD_V0.1.

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❌ Design Errors

• The BC547 transistor symbol used in the design (V0 / V0.1) was of TO-92 type, while the actual PCB footprint was for SOT-type. This caused pin mismatch and made the footprint incompatible.

• The push-button connection was incorrect. It was connected between pin 1 & pin 2 in the schematic, whereas the correct connection should be between pin 1 & pin 3. This made the switch unresponsive as pin 2 was shorted between GND and VCC via the 10k resistor.

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🔶 Workaround for Transistor

• Since the BC547 pinout issue can't be resolved easily on the PCB, better to:
  • Remove the transistor, and
  • Short the Base and Emitter pins.
    This gives direct control of the LEDs to the MCU, and the firmware has been adjusted accordingly.

🔧 Additionally:

• Remove the resistor connected to the Collector pin, as it will be left floating after the transistor is removed.
• Reduce the Base resistor value to 560Ω or less, allowing sufficient current flow from the LEDs to the MCU.

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🔶 Workaround for Push-Button

To make the push-button functional:

• Remove the external pull-up resistor (the internal pull-up is sufficient).
• Carefully cut the trace between pin 2 and GND to isolate pin 2. (This can be tricky but is necessary.)
• Connect pin 3 to GND using a short jumper wire.

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✔️ V0.1 Rework Instructions

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📌 Recommendations for Future Revisions

• Remove the transistors in the LED section entirely:

  • The LED matrix draws low current and can be driven directly by the MCU.
  • This also helps reduce BOM cost and simplifies the layout.

• Double-check all component footprints and connections to avoid similar pin mismatch issues.

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