PineTime · nRF52832 · XT25F32B
BattleTime Memory Map
The watch's internal flash, RAM and external SPI flash, each split into its regions, and each region into what fills it, drawn to scale. Click a box to zoom into it and read what it holds; the path above the map leads back out.
Watchdog
The bootloader leaves the watchdog running when it starts the firmware, with a 5 second timeout. It keeps counting while the chip sleeps and pauses while a debugger has it halted. The firmware must take it over with exactly those settings.
The firmware feeds it only while the button is up. Holding the button for about 5 seconds resets the watch into the bootloader, and 5 seconds more installs the recovery firmware. An update that never confirms itself is rolled back.