The VPX responder device now drives production BattleTech v4.10
through the full transputer/i860 boot, far past the Phase 1 wall:
- iserver boot handshake solved: feeds 3 well-formed 'version' (tag 42)
iserver requests, satisfying startup_handshake()'s 3 transactions.
- i860 download solved: parses the outbound framed renderer messages
(vr_860args/code/data/bss) and absorbs them, staying byte-aligned.
- echo-action reply model validated against board source
(VRENDER/VR_REMOT.C reply() echoes the received action); device
tracks and echoes the last outbound action generally.
Remaining sub-protocol identified and characterized: after i860 boot
the host switches to a FIFO fast path (OUTSW.ASM: 0x40 tag + REP OUTSW
16-bit words to FIFO port 0x154/0x155, gated by ok_to_fifo at 0x160).
The current build stops at velocirender_sync because the device only
implements the slow byte path. PHASE2-PROGRESS.md documents the exact
next steps (FIFO transport + render loop -> Phase 3 OpenGL backend).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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>
CydandClaude Fable 5