73 lines
1.4 KiB
Markdown
73 lines
1.4 KiB
Markdown
# Hardware
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Current target: **PineTime smartwatch**.
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PineTime is an open hardware smartwatch designed by Pine64.
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It is capable of running fully custom firmware.
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## Core Specifications
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Main hardware components include:
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- Nordic **nRF52832** MCU (ARM Cortex-M4F)
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- 64 KB RAM
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- 512 KB internal flash
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- additional **4 MB SPI NOR flash** for assets
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- Bluetooth Low Energy support
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The CPU runs at **64 MHz** and includes a floating-point unit.
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## Display
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PineTime includes:
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- 1.3 inch IPS display
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- resolution **240×240**
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- **ST7789 display controller**
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- capacitive touchscreen controller
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The display is connected through SPI.
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## Sensors
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The device contains several sensors and peripherals:
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- BMA421 accelerometer
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- HRS3300 heart rate sensor
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- vibration motor
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- capacitive touchscreen
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These are typically connected over I²C.
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## Battery
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PineTime uses a small Li-Po battery around **170-180 mAh** capacity.
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Battery life depends heavily on firmware design and BLE usage.
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## Development Constraints
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Important constraints for firmware design:
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- very limited RAM (64 KB)
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- limited internal flash (512 KB)
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- firmware must run entirely from internal flash
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- external flash cannot execute code
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The external flash is mainly used for:
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- fonts
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- assets
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- large UI resources.
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## Future Hardware Support
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Vaka OS is designed primarily for PineTime.
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Portability may be considered later but is **not a primary goal** during early development.
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