Built DOSBox-X from source with a custom VPX link-adapter logging
device (vpx-device/vpxlog.cpp) and captured the game's outbound boot
sequence. Findings:
- Register map confirmed against LINKIO.C: outputData 0x151,
outputStatus 0x153 (polled bit0), resetRoot 0x160, analyseRoot 0x161.
- Reset preamble captured exactly (analyse=0, reset 0->1->0 + status inits).
- The game streams 85298 bytes to outputData that are BYTE-FOR-BYTE
identical to VRENDMON.BTL; first byte 0xF0 = transputer boot-from-link
primary-bootstrap length. Protocol stage 1 (reset + monitor download)
fully characterized; no hidden bulk/interrupt path.
- Production cockpit dump ALPHA_1 added (git-ignored): its BT is v1.1.0.6
with a VRENDMON.BTL byte-identical to the captured stream, so this
result reflects the exact cockpit software. ALPHA_1 is the reference
image going forward (carries RP + production pod/network boot chain).
Adds analyze_capture.py, capture.conf, PHASE1-RESULTS.md. DOSBox-X
source tree and capture artifacts are git-ignored.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Baseline boot test under DOSBox-X confirms the emulation architecture
empirically. Key findings:
- Borland 32RTM/DPMI runtime works under DOSBox-X (risk retired).
- BTLIVE ships a version-mismatched BTL4.RES (1.0.1.2 vs EXE 1.0.1.4);
BTRAVINE (1.1.0.6) is self-consistent and matches this repo's source
(BTL4VER.HPP), so it is the development image.
- With the matched image the game boots through the resource check and
BTL4Application construction, polls the RIO on COM1, then reads the
VPX link at port 0x150, gets 0xffffffff, and fails rcv_protocol with
'length 65535 too big' — the exact VR_COMMS.C path the plan predicted.
Adds emulator/baseline.conf (repro) and emulator/PHASE0-RESULTS.md.
Working binaries (dosbox-x/, image/) are git-ignored.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
CydandClaude Fable 5