handoff: pod bring-up + RGB split

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

scratchpad/SESSION_HANDOFF_20260803.md

@@ -481,3 +481,28 @@ NEW LEAD: @0x4c0904 = the MASTER BTPlayer Performance (team resolve, EndMission
 score heartbeat); our @0x4c083c PlayerSimulation attribution needs re-checking.
 Pipeline: tools/ghidra_reexport.sh -> tools/gapcensus.py -> tools/gapdiff.py.
 NEXT: polish list (killed-by console line, burning wrecks, marker beacon) + field logs from 801.
+
+## 2026-08-06 (evening): POD BRING-UP on Nick's crash cart (ALPHA-MR) + the RGB SPLIT
+ACCESS: Tailscale + Windows OpenSSH on the cart. `scratchpad/pod/podssh.sh` = shell (user@
+100.107.167.96, key ~/.ssh/bt411_pod). ⚠ SSH lands in SESSION 0 with a DUMMY display -- GUI
+apps must run in the CONSOLE session via `schtasks /run /tn BT411Run` (created with /IT), or
+they render nowhere. `tailscale file cp` both ways for files.
+CART: Win10 IoT LTSC 19044 (modern -- our build runs), Intel HD630 + "Trigger 6 External
+Graphics" USB adapter, 4 console displays: DISPLAY3 800x600 PRIMARY (main view) +
+DISPLAY4 800,122 / DISPLAY2 1440,123 / DISPLAY1 2080,124 (all 640x480). COM1 present (RIO).
+NB the cart was previously joined to ANOTHER tailnet (node "alpha-mr", different account);
+its stale state was renamed to tailscaled.state.nickbak (restore = stop svc, rename back).
+⭐ THE RGB SPLIT (decoded, pod-hardware.md): ONE VGA port's R/G/B lines drive THREE mono MFDs.
+L4GAUGE.CFG assigns each port a bit-mask AND a channel (Comm=red/Mfd2=green/Heat=blue on
+clut2; Mfd1=red/Mfd3=green on clut1; sec=rgb rot270), and BuildSecondaryColor (L4VB16.cpp)
+writes exactly ONE colour component per port -- that IS the split. The "1280x480 span" is two
+VGA ports x three channels.
+BUILT: BT_POD_SURFACES=1 (bare 640x480 pictures, no on-screen banks, no Flight Controls pad,
+placement receipts naming the physical monitor) and BT_POD_RGB=1 (one window per VGA PORT,
+compositing its planes into R/G/B; channel read live so Eng-page swaps follow). Both verified
+locally AND live on the cart.
+LAUNCHER TRAPS: a bare MP.EGG exits the mission loop immediately (no relay); BT_FE_SOLO parks
+at the mission menu -- neither lights the panels. Use `-egg PODTEST.EGG` (a solo egg).
+OPEN: eyeball question -- is the cart splitter-wired (3 monitors per output, use BT_POD_RGB) or
+one-panel-per-output (use BT_POD_SURFACES)? Windows showing 3 separate 640x480 displays hints
+per-panel. Also unmapped: Left/Right Weapons + radar have no panel on this 3-panel cart.