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