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.
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