Base

Sea Breeze Clock

The Sea Breeze Clock provides ultimate comfort for deep sleepers. Featuring a built-in humidifier, temperature sensor displayed on screen, and a gentle wake-up vibration function, it is designed to help you start your day feeling refreshed as if you have woken up on a private island.

Members

• Yuval Levy (yuvlev-1@student.ltu.se)
• Calle Rautio (calrau-1@student.ltu.se)
• Simon Larsson (simlar-0@student.ltu.se)

Hardware Features

• Display
• Humidifier for sea effect
• Backup battery for RTC and alarm time
• Speaker
• User interface (encoder / button)
• Programming interface
• Temperature measurement
• Fan for (hamster sized) sea breeze effect
• USB MINI connection
• Haptic actuator for SUPER GENTLE WAKE
• Hard(ish) protective case for the board

Functionality and SW features

Besides mandatory functionality the Final Countdown features:

• Set Clock with long push and alarm time with short push. Change of volume with rotary button on default screen.
• CLI can control temperature sensor, speaker volume, intensity of buzzer, and fan speed control from CLI, and everything else.
• Maybe additional features.

Individual grading goals and contributions

Yuval Levy

3

• Contribute to the mandatory goals

4

• Backup battery (HW & SW)
• Haptic actuator (HW & SW)

5

• Speaker (HW & SW)
• Power optimization (SW)
• Humidifier HW

Calle Rautio

3

• Contribute to the mandatory goals

4

• Humidifier SW
• Fan HW
• Fan SW
• HW component optimization (fewer MOSFETS)

5

• Speaker (HW & SW)

Simon Larsson

3

• Contribute to the mandatory goals

4

• Backup battery (HW & SW)
• Temperature on display SW
• Rotary encoder HW

5

• Speaker (HW & SW)
• Rotary encoder SW
• Power optimization (SW)

HW References

• MCU (QDAA QFN40) (included)
• I2C Display
• Humidifier for sea effect [blocked] DATASHEET MISSING! application (included)
• Holder for backup battery (CR2032)
• Miniature speaker
• DAC and amplifier for the speaker
• Haptic Actuator
• Rotary encoder, preferably with built-in button (included)
• Push button for resetting the program [blocked] (included, alternatives: TE Connectivity 1825910-7, Alps Alpine STTSKHHBS) (included)
• Fan for wind effect (hamster sized)
• LED (included)
• USB Mini (included)
• Analog temperature sensor (included)
• Serial programming header (included)
• Serial communication header to host, over dev-kit VCP (included)
• Case made either of wood or 3D-printed

Other Parts

• Schottky diode ZLLS500TA (link1, link2) x 3 (3 per board)

SW References

Crates/dependencies used in the project:

• heapless – Fixed-capacity collections
• cortex-m – Low-level access to Cortex-M processors
• cortex-m-rtic – Real-time interrupt-driven concurrency
• cortex-m-rt – Minimal runtime for Cortex-M
• embedded-hal – Hardware abstraction layer for embedded systems
• panic-rtt-target – RTT-based panic handler
• panic-halt – Halts execution on panic
• rtt-target – Real-time tracing for embedded devices
• systick-monotonic – Monotonic timer using SysTick
• dwt-systick-monotonic – Monotonic timer using DWT and SysTick
• nb – Non-blocking operations abstraction
• usb-device – USB stack for embedded systems
• usbd-serial – USB-to-serial converter
• usbd-hid – USB HID implementation
• embedded-graphics – Graphics library for embedded displays
• ssd1306 – Driver for SSD1306 OLED displays
• libm – Math library for no_std environments
• profont – Monospace bitmap font for embedded graphics
• nrf52833-hal – HAL for nRF52833 microcontrollers