Glossary

ADFU: Actions’ USB service mode (“upgrade mode”), USB ID 10d6:10d6. Entered with adfu_reboot.
bank: A piece of program code with its own address that is loaded into a RAM window when called. Banks of one group share the window. See Programs (.AP).
bank tail: The zeros between a bank’s end and the end of its 1 KB file slot; where new code is placed.
checker: A script that runs old and new code side by side in thumb_sim.py and compares the results; every program patch has one.
COMMON.STY: The resource file all programs share. Ids with bit 15 set refer to it.
engine: MENGINE.AP, the background process that plays music, controlled by messages.
Graphite: The new interface design built in this project.
host test: The test of the new C code on the computer, against a simulated disk, library, browser and engine (design/playlist/host/).
keyed draw: A display driver call that draws only pixels whose 16-bit value is above a key (function 38).
LFI: The firmware container: header, directory, 137 files, additive checksums.
list style: A list-box record of COMMON.STY (0x6000 to 0x6008) that decides how a list looks and which parts it shows.
readback: The image read from the player after a write (x91_dump/flash_work/readback.bin); it identifies what is on the player.
shared code: The SDK’s interface code (status bar, lists, menus, screensaver, key filter, timers) linked into every program separately.
sideways copy: The second, column-wise copy of a picture that serves as a scrolling text’s background.
release image: An image design/build.py makes from the stock image; RELEASE in build.py holds the sha256 of each theme’s 1.0.0 image, and --check compares.
stage: One step of the design before release 1.0: one builder (design/build_stageN.py, now in the git history), one flash. Release 1.0 is stage 27, built in one go.
status bar: The top 20 rows: card mark, Bluetooth mark, battery, and (main menu) the clock; since stage 24 also menu and list names or the item counter.
STY, MCG, AP, DRV, FON: Resource file, menu file, program, driver, font.
theme: The same design in another accent colour, built as its own image.