nRF52 BLE: wait for LFXO crystal before enabling SoftDevice (fixes t1000e hanging at reboot)#1939
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weebl2000 wants to merge 2 commits intomeshcore-dev:devfrom
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nRF52 BLE: wait for LFXO crystal before enabling SoftDevice (fixes t1000e hanging at reboot)#1939weebl2000 wants to merge 2 commits intomeshcore-dev:devfrom
weebl2000 wants to merge 2 commits intomeshcore-dev:devfrom
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The Adafruit framework starts the LFXO in init() but never waits for EVENTS_LFCLKSTARTED. On first boot the filesystem format (~600ms of page erases) gives the crystal time to stabilize. On subsequent boots only quick mounts happen, so sd_softdevice_enable() inside Bluefruit.begin() can be called while the crystal is still starting, which hangs indefinitely. Poll EVENTS_LFCLKSTARTED before Bluefruit.begin() so the wait is exact rather than a blind delay. fixes: meshcore-dev#1780
This was referenced Mar 6, 2026
weebl2000
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The Adafruit framework starts the LFXO in init() but never waits for EVENTS_LFCLKSTARTED. On first boot the filesystem format (~600ms of page erases) gives the crystal time to stabilize. On subsequent boots only quick mounts happen, so sd_softdevice_enable() inside Bluefruit.begin() can be called while the crystal is still starting, which hangs indefinitely.
Poll EVENTS_LFCLKSTARTED before Bluefruit.begin() so the wait is exact rather than a blind delay.
fixes: #1780
Please try the firmware for yourself by building here.