Rule 15 in the stream harness holds both halves of the minimum
(grblHAL-glowforge f7e8c17, pinned here): no emitted burst falls below
laser_pulse_min_ticks, excepting one clipped by fire going off mid-burst,
and the levels too faint to fill a window still render their exact
average density. Checked against a run at minimum 1 so it cannot pass
vacuously - level 2 goes from 444 bursts of one tick to 147 of three at
the same density, and levels already above the minimum are unchanged.
Four bench ladders settle the base period at 20. The same six rungs
marked in all of them, and the matched pairs across periods separate the
variables: at identical pulse length, halving the density killed the
mark; at identical density, varying the pulse 3x changed nothing. Feed
does not move it either - 10 percent at F100 carries 44 percent more
energy per mm than 20 percent at F300, which marks, and still left
nothing. The low-end marking limit is average power, not dose per length
and not pulse length.
The F100 trace separates two failures that look alike on the material:
seven current segments for eight rungs, anchored by a flat saturated
final segment that can only be full density, put 5 percent at no
discharge at all and 10 percent at a full 15 seconds of current with no
mark. Only the first is ours, and the minimum pulse is the answer to it.
Also recorded: the factory's Precision Power 1 runs a 19.53 percent FIRE
duty cycle at full PWM duty, and its 1-100 scale maps onto density
18.9-79.5 percent, so its 1 percent is the bottom of the useful band
rather than 1 percent of the range. Under the density model $35 and $36
are that same control - a density floor and ceiling - which makes the
user-facing scale a settings choice rather than new code.
Four new sessions in the stream harness cover the model (grblHAL-glowforge
2bca017, pinned here). Density renders the commanded level exactly -
levels 2, 3, 7, 15, 25 and 38 came back as 0.0158, 0.0237, 0.0551,
0.1182, 0.1969 and 0.2993 against level/127 of 0.01575, 0.02362, 0.05512,
0.11811, 0.19685 and 0.29921 - S1000 renders 1.0000 and still ends dark,
every power byte carries full duty, and a level change inside a run costs
no stream byte where analog ships one per level.
Rule 13 is the one worth having: the same job run under both models
produces an identical motion grid tick for tick, and all 20051 density
FIRE ticks fall inside the 169776 the analog run fired. The model masks
the core's fire state and never sources one, measured rather than argued.
Rule 14 covers the idle-gap fix: a standalone S between moves, from a
sender slow enough to drain the planner, now fires each move at its own
level (28338 ticks each at duties 30, 52 and 84). Before the fix duty 30
held all 85014 and the other two levels never appeared. That closes
"Next work" item 18, which this work opened earlier today.
The harness now derives its expectations from the board's floor and
chains two launches over one settings file, because the core precomputes
the S to duty mapping once when the spindle is enabled: $35 written at
runtime persists and reports immediately but only enters force at the
next controller start. That is recorded in BRINGUP beside the existing
defaults note, and laser.power-floor's failure message now says so.
Acceptance: the density path shipping off by default is inert until
laser_power_model is set, and the laser tests' covers already name
grblhal-glowforge src/**; the model's own acceptance test waits on the
bench drill that picks the base period.
The pthresh ladder on scrap puts the tube's two thresholds far apart: the
discharge strikes between 2 and 3 percent duty, but nothing lases usefully
below 16 percent (PWMSAR 20), and the rungs between show only a spot at
each line start. $35 ships at 16 (grblhal-glowforge 9466f76, pinned here).
The drill said current lift-off and first mark share a rung; this run
falsifies that, so its docstring and read-the-material text now name both
thresholds and warn that a start-of-line spot is below the threshold, not
at it.
A start-of-line spot is also what a full-power leak at a kernel run start
would look like, so laser_stream_test gains a ladder session (rule 10):
every FIRE tick must ride a commanded duty, and the fire ticks must divide
evenly across rungs. Both hold exactly - six commanded duties, no others,
and 28296 fire ticks on every rung - so the spots are the tube, not the
stream. The harness now derives its expectations from the floor, which
moves the M4 session's S500 plateau from 63 to 73.
laser.power-floor is a new auto acceptance test, the suite's only
non-firing one: a machine must actually carry the commissioned floor,
since stored settings beat freshly baked defaults.
Three cloud cuts of one square at Precision Power 1, 100 and Full Power
show what the analog path is competing with: the power byte is pinned at
127 in all three, dose is FIRE-bit density on a fixed 7-tick period with
the on-count dithered between adjacent integers, and the power setting
never reaches the machine at all. Facts bank and item 17 carry the
numbers; CAMPAIGN-LOG carries both sessions.
rsyslog replaces busybox syslogd/klogd (VIRTUAL-RUNTIME_base-utils-syslog,
trimmed PACKAGECONFIG) and becomes the only log writer: the appended
/etc/rsyslog.conf sets the inputs and the ff_line format and includes
the per-logger rules that `forgectrl --render-syslog` renders from the
machine settings at boot. forgefirm-logrotate becomes forgefirm-logging:
render before rsyslog starts (S19), sweep the pre-syslog log files into
/data/forgefirm/legacy-logs once, and rotate the tree at boot and hourly
by rename + HUP instead of copytruncate. Pins bumped to the pushed
forgectrl (syslog emitter, Logs tab, export), grblHAL-glowforge (syslog
emitter) and python3-gfhardware apps (syslog handlers, capture dir);
the CI harnesses set FFLOG_STDERR=1 so failure diagnostics keep the
controller's log lines. BRINGUP carries the bench validation checklist
(Next work item 14); this is an image change and rides the next flash.
- LIGHTBURN.md: mandatory "Before you cut" safety section; the
walkthrough now reflects the firing machine (dry runs need the
layer output off or M5; live first-cut instructions); the homing
entry documents homing_mode and the gfcloud method; the machine
address is a placeholder.
- README.md: condensed safety section linking the full text and the
regulatory notes.
- INSTALL.md: "Regulatory and legal" section ahead of the install
steps; routine updates route through the panel updater rather than
the installer.
- BRINGUP.md: the release signing key is described as held offline
(no on-disk path); bench address and credential notes removed;
Next-work item 7 corrected (the installer embeds the production
release key); status entry for audit remediation Phases 0-1; the
GATE A kernel drills join the pending image-flash checklist.
- bench scripts: the target host comes from GF_HOST (or argv) instead
of a hardcoded address.
- laser_stream_test.py: per-session controller runs with a hermetic
cooling-verdict publisher; new assertions that every stream
terminates with FIRE clear (including M3 held to stream end) and
that no FIRE bit rides a zero-step gap; a cycle-churn session
exercises the stop/start seams.
Audit findings D-1, D-2, D-3, D-5, D-10, D-12, B-10, and the harness
half of D-4/G-1.
BRINGUP item 2: grbl-mode laser software implemented + bench-verified
without fire (record in the gate list); first light pending.
LIGHTBURN.md: arming/button-press operation, S-max 1000, fire gates.
scripts/bench/laser_stream_test.py: host-side stream-dump contract
verification against the null-sink build.
ScottW514