Snapshots of the non-streaming camera no longer fail 409: the worker borrows the mux for one frame (stream viewers see a short freeze). Stream switches wait up to 3 s for the previous pin to drain. Arbitration compares the engine home camera, not the transiently borrowed pipeline camera. Index page: single toggled stream with retry plus a head-peek button.
Adds the design matrix and its supporting tools, and records in BRINGUP
what the 60-run matrix overturned: sub-40-percent duty mimics flow
(three of five dead-pump trials looked healthier than a working pump),
the operating point and threshold now rest on 25 pooled observations,
periodic re-checks are thermally free with the fans running, and the
settle gate closes a bench-proven miss. Also records what is NOT yet
validated - warm-loop baselines and behaviour under laser heating - as
first-light commissioning items.
Records why the temperature formula changed (and that everything
derived from the old one had to be re-derived), the flow
characterization data at both heater duties, the false negative that
killed the dT-threshold design, and the downstream-rise check that
replaced it. Adds flow_characterize.py to the bench kit.
BRINGUP records the gate as complete with tach-verified results;
LIGHTBURN.md documents the per-layer Air Assist toggle driving the
cut-profile ventilation; fan_test.py joins the bench kit.
No factory X/Y home switches (unpopulated IO header only). Current
sensing is a dead end (PIC attrs are setpoints; stalled steppers do
not draw more current). Primary: head lis2hh12 accelerometer contact
detection (needs IIO bring-up). Fallback: low-current soft-bump
against the hard stops. Camera homing stays a future option.
Scope on GPIO2_IO30 (the SoC FIRE drive): two 2.000 s FIRE windows,
the second terminated only by the SDMA end-of-data backstop. Measured
2.0000 s exactly with clean edges on BOTH termination paths - normal
completion and true underrun (streaming=1, kernel underrun state
reached and acked; fire_test.py gains the U mode). The backstop drops
FIRE within one tick regardless of how the stream dies.
With the waveform, stream-path, latch, topology, and interlock-
semantics results from earlier today, every standing hardware
verification gate for live fire is now passed; what remains is the
laser-milestone software and a chain-armed first-light procedure.
fire_test.py phases A/B with the scope on the PSU LASER_ON pin, power
byte 0 throughout, HV unpowered, operator-executed unlock: latch LOCKED
severs FIRE entirely (pin flat + kernel laser_enable 0 under 40k
streamed fire bits); latch unlocked with the chain unarmed shows FIRE
live kernel-side while the PSU pin stays flat - the factory board
gates LASER_ON behind OK_2_FIRE exactly like the OpenGlow AND design.
interlock_circuit semantics pinned by the 13-to-7 transition: b0
LASER_ON monitor active low, b1 FIRE active high, b3 latch 1=locked.
The 1-tick FIRE drop measurement is deferred (SoC net inaccessible;
PSU pin needs an armed chain) - documented with both closure paths.
Power-bytes-only program played by the pulse engine with the scope on
LASER_PWM: full duty staircase observed, run-start 100 percent duty
reset confirmed on the pin, consecutive-power-byte drop confirmed
(second byte of a back-to-back pair discarded), and duty persists
after end-of-data - the laser-off guarantee rests entirely on FIRE.
Zero motion (motor_lock=15 + no step bytes; position counters pinned)
and the laser chain silent throughout. Adds pwm_stream_test.py to the
bench kit and records the FIRE/OK_2_FIRE/LASER_ON/HV_EN naming from
the OpenGlow LASER SAFING sheet.
Direct PWMSAR duty steps with the machine in the locked state
(controller stopped, cnc disabled so steppers are unpowered, laser
latch locked, lid closed; laser_on_sampled stayed 0 throughout).
Measured on the pin: 25.0 us period / 40 kHz stable across the full
duty range; 50/25/75 percent confirmed visually; low end
cursor-measured 6.4 vs 6.3 percent commanded (PWMSAR=8), clean pulse.
Matches the register-level audit numbers (divider 13 x 127 counts).
Adds pwm_sweep.py / pwm_hold.py to the bench kit and records the two
remaining pre-live-fire gates (1-tick laser drop at underrun via the
stream path with FIRE observable under a locked latch; interlock
readback semantics) in BRINGUP.
Full design job (rapid / M4 cut trace / return rapid) ran smoothly end
to end on grblHAL-glowforge over TCP:23, laser locked. Records the two
driver fixes the first attempts surfaced: locked laser spindle and
continuation-wakeup cursor alignment.
Operator confirmed smooth, near-silent motion on a full observation run
(slow/fast/diagonal/zigzag jogs to 200 mm/s) under grblHAL-glowforge
with the factory-true analog config. Milestone 2 closed.
The step backend now lives in github.com/ScottW514/grblHAL-glowforge
(grblHAL driver convention: core submodule, driver.c HAL, board header).
Add build-glowforge.sh, update the BRINGUP runbook (no -t throttle,
EEPROM path, kill-before-scp, producer stats line, reset/disconnect
semantics), and teach bench_m2.py to parse the F: status field (no
spindle registered = no FS: field). Settings-write crash fix is
upstream as grblHAL/core PR 999.
Extract the factory motion profile from the _RESOURCES pulse streams
(new puls_profile.py): 700/590 mm/s2 X/Y accel on v2.6.0 firmware,
202 mm/s travel peak at the 28160 Hz travel tick, PIC currents X 135/33
and Y 22/5 run/hold, decay mode 1. Add the bench_m2.py round-trip jog +
feed-hold suite (all green 2026-08-02: sustained 200 mm/s, exact
returns, clean hold/resume, zero underruns) and update BRINGUP.md:
board moved to a fixed lease at 172.16.1.97, analog config now applied
by the sink itself, $RST=$ note for stale stored settings.
BRINGUP.md is the cold-start reference: project status (audit phases
0-5 complete, Phase 6 spike achieved - first grblHAL-commanded motion
2026-07-26), bench/board access, build+deploy procedures, the step
backend runbook incl. the required analog machine config, the measured
hardware facts bank, and the ordered next-work list. scripts/bench/
preserves the hardware-verification tools (underrun feeder, end-of-
data protocol bench, PWM register check, cross-build scripts).
ScottW514