SDD
8588340527
hostload.py drives one rdebug connection: jump(malloc) for the COFF buffer, poke the COFF, poke the loader at 0x01880000, write the descriptor, call the loader, and verify status 0 plus app evidence (marker cells or xhello stage 6 and a VRAM screenshot). --tftp uses the existing tftpc.bin fetch instead of a host poke. Adds evidence for two/three fresh boots and appends the integrate section to dwt/notes/LOADER.md, including the bit-offset result-block layout and the create_process clobber of the descriptor.
dwt/loader — the COFF loader half of the app loader
Loads a GSPLNK-linked COFF image that is already in RAM into a first-class
process on the VT1200 OS. The transport (TFTP) is separate; this half takes a
buffer and length, picks the addresses from the COFF, and calls
create_process.
Read dwt/notes/LOADER.md for the full report and
dwt/notes/LOADER_CROSS.md for the transport interface.
Files
| file | purpose |
|---|---|
loader.asm |
the loader; linked at bit 0x01880000, raw .bin 1220 B |
marker.asm |
acceptance app with .text/.data/.bss at three addresses |
coff.py |
TI COFF reader/dumper (summary, raw, manifest) |
build.sh |
GSPA/GSPLNK wrapper; keeps the linked COFF |
reldemo.sh, rel_a.asm, rel_b.asm |
relocation and position-dependence demo |
loader.lua |
debugger-assisted harness (no network, no rdebug) |
probe_os.lua |
heap-list and register-write probe used to design the harness |
build/ |
linked loader/app COFFs, raw .bins, maps, listings |
evidence/ |
run logs, COFF dumps, the xhello window frame |
work/ (the DOS tools extracted from the SDK floppy) and run/ (private
NVRAM/cfg) are local scratch and ignored.
Build
./dwt/loader/build.sh dwt/loader/loader.asm 01880000
./dwt/loader/build.sh dwt/loader/marker.asm 018C0000 018D0000 018D8000
./dwt/loader/build.sh dwt/gui/xhello.asm 01840000
./dwt/loader/reldemo.sh
build.sh takes SOURCE.asm [TEXT_ORIGIN [DATA_ORIGIN [BSS_ORIGIN]]]
(origins are bit addresses) and writes build/<name>.coff, .bin, .map,
.lst, .obj.
Run (debugger-assisted, no network)
VT1200_SKIP_LEVEL1=1 LOADER_AT=2500 LOADER_END=2620 \
LOADER_COFF=dwt/loader/build/marker.coff LOADER_OUT=$PWD/dwt/loader/evidence \
/home/arti/code/k-space/mame0289/vt1200 vt1200 \
-rompath harness/mame/roms -video none -sound none -nothrottle -skip_gameinfo \
-nvram_directory $PWD/dwt/loader/run/nvram \
-cfg_directory $PWD/dwt/loader/run/cfg \
-debug -debugger none \
-autoboot_script dwt/loader/loader.lua -autoboot_delay 0
The script pokes the loader at 0x01880000 and the COFF at LOADER_BUF
(default 0x01900000), writes the descriptor, and sets PC. It never uses the
network, the rdebug service or a firmware transport.
Knobs: LOADER_MODE=1 (callable/return instead of debug-resume),
LOADER_A8_DESC=1 (descriptor in A8), LOADER_SNAP=1 (PNG at LOADER_END),
LOADER_VERBOSE=1, LOADER_TRACE=1.