An active antenna on the roof received nothing until the modem's
antenna supply was switched on (AT+CVAUXV=3050, AT+CVAUXS=1); then +5.5
dB over the passive one. The settings reset on every modem restart and
AT&W doesn't keep them, so interface 03 is reserved as /dev/sim7600-at
(ModemManager ignores it) and a udev-started oneshot re-applies them.
gpsd now re-attaches via gpsdctl after re-enumeration. Verified with a
live modem reset: antenna, LTE and the GNSS fix all recovered unattended.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
With both adapters attached at power-on, pcan registered first and took
can0, and the udev rule renamed it to can_pcan, confirming the race and
the fix. qmi_wwan auto-loaded, povo auto-connected below WiFi, and gpsd
came up on the stable symlink.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
mttcan and pcan both load at boot, so the PCAN adapter could take can0
and push the onboard controller to can1. A udev rule now names them
can_onboard (platform c310000.mttcan) and can_pcan (USB 0c72:000c),
both outside the canN pool so a transient canN can never collide.
Also records why the SIM7600 needs nothing more: ModemManager and NM
don't use ttyUSB numbers, and gpsd already uses a symlink.
can_onboard is verified live; can_pcan is checked against the driver
source only (adapter not plugged in).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>