This video demonstrates the successful implementation of the classic video game Doom on a Xiaomi Mi Band 8, building upon previous efforts to reverse-engineer its display and touchscreen. The creator showcases fully running Doom, detailing the in-game controls via the smartwatch's interface. A significant technical challenge involved shrinking the game to fit within the Mi Band's limited 2MB internal flash and 1MB RAM, as its external 128MB SPI flash could not be directly memory-mapped, making on-demand loading impractical. Despite these constraints, the game runs surprisingly well with fair smoothness, high contrast, and good color, representing a notable achievement in embedded system optimization for gaming.
Summarizing Doom on Xiaomi Mi Band 8: A Technical Achievement
0:00 Doom on Mi Band 8: The video announces and demonstrates full Doom support on the Xiaomi Mi Band 8.
0:11 Prior Reverse Engineering: Previous videos involved custom firmware and complex reverse engineering of the Mi Band's display and touchscreen.
0:23 Fully Functional Game: The current achievement is a fully running version of Doom on the device.
0:28 Touchscreen Controls: The game is controlled by tapping the top for the menu/start and using the touchscreen for movement (forwards, backwards, left, right) and shooting.
1:00 Gameplay Demonstration: A live demonstration shows the game in action, though controlling it while filming proves challenging.
2:18 Memory Optimization: Significant work was done to shrink Doom to fit within the Mi Band's limited 2 megabytes of flash and 1 megabyte of RAM.
2:28 External Flash Limitations: The external 128 megabytes of SPI flash cannot be directly memory-mapped, making it difficult for Doom to use for on-demand loading.
2:51 Internal Memory Execution: As a result, Doom now runs almost completely within the internal 2MB flash and 1MB RAM.
3:01 Performance: The game runs "fairly smooth" with high contrast and colors, surprising given the hardware limitations.