Hardware: WittyPi4 L3V7 <-> pi zero 2w
power supply: reliable usb-c power supply (no battery atm)
schedule: on_5m_every_20m.wpi
The issue I'm having is that after around 24 hours, the pi appears to not (fully) shutdown and the schedule seems to cancel.
In this state, the red LED on the witty is on constantly and the green LED on the pi is also on but the pi is no longer reachable via SSH.
The button on the witty doesn't produce any action, I have to unplug the witty unit from the mains to recover.
I would like to get to a state where I can run the routine for several weeks without this happening, is that a realistic goal?
Any tips on things that I could try to identify why the pi isn't fully shutting down? (as far as I can see, the header connections are all good.). I guess my next step would be to try hooking it up to a monitor next time its in this state.
I'm including the last 2 entries in wittyPi.log below (the shutdown at 12:05 did not complete):
[xxxx-xx-xx xx:xx:xx] Witty Pi daemon (v4.21) is started. [xxxx-xx-xx xx:xx:xx] System: Debian GNU/Linux 13 (trixie), Kernel: Linux 6.12.62+rpt-rpi-v8, Architecture: arm64 [xxxx-xx-xx xx:xx:xx] Running on Raspberry Pi Zero 2 W Rev 1.0 [xxxx-xx-xx xx:xx:xx] Witty Pi is not detected, retry in one second... [xxxx-xx-xx xx:xx:xx] RTC offset register has value 0x77 [xxxx-xx-xx xx:xx:xx] Seems RTC has good time, write RTC time into system [xxxx-xx-xx xx:xx:xx] Writing RTC time to system... [2026-03-03 11:40:27] Done :-) [2026-03-03 11:40:27] Firmware ID: 0x37 [2026-03-03 11:40:27] Firmware Revison: 0x07 [2026-03-03 11:40:27] Current Vout=5.21V, Iout=0.17A [2026-03-03 11:40:27] System starts up because scheduled startup is due. [2026-03-03 11:40:32] Schedule next shutdown at: 2026-03-03 11:45:00 [2026-03-03 11:40:33] Schedule next startup at: 2026-03-03 12:00:00 [0:00:30.849001029] [1104] INFO Camera camera_manager.cpp:340 libcamera v0.6.0+rpt20251202 [0:00:30.941143685] [1422] INFO IPAProxy ipa_proxy.cpp:180 Using tuning file /usr/share/libcamera/ipa/rpi/vc4/imx477.json [0:00:30.961356237] [1422] INFO Camera camera_manager.cpp:223 Adding camera '/base/soc/i2c0mux/i2c@1/imx477@1a' for pipeline handler rpi/vc4 [0:00:30.961485091] [1422] INFO RPI vc4.cpp:445 Registered camera /base/soc/i2c0mux/i2c@1/imx477@1a to Unicam device /dev/media3 and ISP device /dev/media0 [0:00:30.961551289] [1422] INFO RPI pipeline_base.cpp:1111 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml' [0:00:30.983413789] [1104] INFO Camera camera.cpp:1215 configuring streams: (0) 1920x1080-BGR888/sRGB (1) 640x480-YUV420/sYCC (2) 2028x1080-SBGGR12_CSI2P/RAW [0:00:30.984199414] [1422] INFO RPI vc4.cpp:620 Sensor: /base/soc/i2c0mux/i2c@1/imx477@1a - Selected sensor format: 2028x1080-SBGGR12_1X12/RAW - Selected unicam format: 2028x1080-pBCC/RAW [2026-03-03 11:40:50] Send out the SYS_UP signal via GPIO-17 pin. [2026-03-03 11:40:51] Pending for incoming shutdown command... [2026-03-03 11:44:59] Shutting down system because scheduled shutdown is due. [2026-03-03 11:44:59] Halting all processes and then shutdown Raspberry Pi... [xxxx-xx-xx xx:xx:xx] Witty Pi daemon (v4.21) is started. [xxxx-xx-xx xx:xx:xx] System: Debian GNU/Linux 13 (trixie), Kernel: Linux 6.12.62+rpt-rpi-v8, Architecture: arm64 [xxxx-xx-xx xx:xx:xx] Running on Raspberry Pi Zero 2 W Rev 1.0 [xxxx-xx-xx xx:xx:xx] Witty Pi is not detected, retry in one second... [xxxx-xx-xx xx:xx:xx] RTC offset register has value 0x77 [xxxx-xx-xx xx:xx:xx] Seems RTC has good time, write RTC time into system [xxxx-xx-xx xx:xx:xx] Writing RTC time to system... [2026-03-03 12:00:27] Done :-) [2026-03-03 12:00:27] Firmware ID: 0x37 [2026-03-03 12:00:27] Firmware Revison: 0x07 [2026-03-03 12:00:27] Current Vout=5.22V, Iout=0.1A [2026-03-03 12:00:27] System starts up because scheduled startup is due. [2026-03-03 12:00:33] Schedule next shutdown at: 2026-03-03 12:05:00 [2026-03-03 12:00:33] Schedule next startup at: 2026-03-03 12:20:00 [0:00:30.099797123] [1104] INFO Camera camera_manager.cpp:340 libcamera v0.6.0+rpt20251202 [0:00:30.197503217] [1424] INFO IPAProxy ipa_proxy.cpp:180 Using tuning file /usr/share/libcamera/ipa/rpi/vc4/imx477.json [0:00:30.216501446] [1424] INFO Camera camera_manager.cpp:223 Adding camera '/base/soc/i2c0mux/i2c@1/imx477@1a' for pipeline handler rpi/vc4 [0:00:30.216629779] [1424] INFO RPI vc4.cpp:445 Registered camera /base/soc/i2c0mux/i2c@1/imx477@1a to Unicam device /dev/media3 and ISP device /dev/media0 [0:00:30.216696706] [1424] INFO RPI pipeline_base.cpp:1111 Using configuration file '/usr/share/libcamera/pipeline/rpi/vc4/rpi_apps.yaml' [0:00:30.238443842] [1104] INFO Camera camera.cpp:1215 configuring streams: (0) 1920x1080-BGR888/sRGB (1) 640x480-YUV420/sYCC (2) 2028x1080-SBGGR12_CSI2P/RAW [0:00:30.239219727] [1424] INFO RPI vc4.cpp:620 Sensor: /base/soc/i2c0mux/i2c@1/imx477@1a - Selected sensor format: 2028x1080-SBGGR12_1X12/RAW - Selected unicam format: 2028x1080-pBCC/RAW [2026-03-03 12:00:44] Send out the SYS_UP signal via GPIO-17 pin. [2026-03-03 12:00:44] Pending for incoming shutdown command... [2026-03-03 12:04:58] Shutting down system because scheduled shutdown is due. [2026-03-03 12:04:59] Halting all processes and then shutdown Raspberry Pi...
It is likely that your Raspberry Pi crashed during the shutdown, and its TXD pin was stuck at HIGH state. Witty Pi checks the TXD pin voltage to know if your Pi is really off.