PineTime Hardware Wishlist

This page contains a list of things people wish PineTime did differently

Hardware

• Long pressing the button should power-cycle the watch without any software being involved
• Other display tech could be explored. A transflective LCD would probably be a nice option. Or potentially OLED?
• Touchscreen should possibly have a configurable sensitivity level for both glove-wearing and droplet-resistance. Preferably it should still be a capacitive one, a resistive touchscreen would have too many trade-offs.
• A slightly bigger 256×256 pixel graphics display size is preferable for its binary alignment, affording some low-level simplicity – it has the property that its X and Y coordinates are each addressable with a single byte, with no out-of-bounds; its total number of pixels is 65536 (another power of 2), and each pixel is addressable with exactly 2 bytes, with perfect efficiency. The IBNIZ (Ideally Bare Numeric Impression giZmo) virtual machine, designed for fun minimalist demoscene graphics, has chosen 256×256 for its virtual display, and makes use of these simplicity advantages. If PineTime also chose 256×256 then it would be a target platform for unclipped IBNIZ demoscene programmes, which would be really fun to play around with on one's wrist!
• A full 16-bit redraw on the display takes 120ms at the very least, which is 8Hz (although modest optimization is possible by adopting 12-bit color). A smooth scrolling/usage/animation experience would be 30Hz minimum, preferably 60. Display redraw is currently bottlenecked by the nRF52832 maximum SPI clock (8MHz).
• Some sort of scroll wheel would be nice for convenience.
• Changed GPIO assignment so more functionality is available (i.e. NFC and VSYNC)
• Wireless charging, or Qi Charging capability
• An external RTC circuit saving the current time to allow the main MCU go to deep-sleep.
• nRF5840 update: QSPI, CryptoCell + Secure Key Storage, has more RAM, a coprocessor and the possibility to expose USB through power pins
• Preferably a pre-certified MCU module with a ceramic antenna
• Version without sensors but maybe bigger battery
• A couple of pins on the programmer connector to allow UART while developing (currently there is a TX test point on PCB). (Note: There's ARM SemiHosting and Segger RTT)
• Connect the pin of LCD controller that allows RD/WR from it in order to save RAM on the MCU. (The MOSI pin for the SPI is already connected to the nor flash that shares the same pins, pin number is P0.04)
• LCD must be centered on case. Currently is not and watchfaces seems different when clock is put on the other wrist.
• A NFC antenna around the case, connected to the NFC pins.
• Used sensors should be NDA-free and preferably also blob-free. For example the BMA421 accelerometer doesn't have a datasheet (it seems private to some hardware integrators): a more open one would be much easier to develop for. Special attention should be paid to advanced features, such as step counting integration or flick detection.
• PineTime SoC could support USB or have a FTDI chip with the relevant pins exposed. It could allow flashing a sealed device, just like Arduinos work. The same USB-C could also be used for charging.
• A bigger pulldown resistor for the power button, because 100k still leaks a noticeable amount of power when the button is always on.
• Ceramic Bluetooth antenna for better signal reception
• Ultra low quiescent current PMIC for better deep sleep. Better shipping/storage/turned off mode
• Separate RTC chip to maintain time setting through MCU reset
• Battery charger IC with built-in "fuel gauge" functionality for better estimation of battery capacity