• OIL level sensior (was ODD DNS behaviour on Pi ZERO W with Bullseye OS)

    From The Natural Philosopher@3:633/10 to All on Wed Nov 19 10:08:52 2025
    On 18/11/2025 23:15, Daniel James wrote:
    On 18/11/2025 12:08, The Natural Philosopher wrote:
    As part of my enhancements to the home controller, I want to send
    email warnings of low heating oil level.

    This sounds rather like something I have been planning to do. AAMOI how
    are you measuring the oil level?


    Oh. I designed a board with

    - a Pi Pico W.
    - a three pin temperature sensor ( TMP36) to monitor outside temperature
    - an ultrasonic transmitter/receiver ( HCRS04) on it
    - a nano power timer that (Was a sparkfun nano power switch TPL5110
    until I blew it up and replaced it with a sub-board with an Adafruit
    TPL5110 Low Power Timer ) wakes up every 2 hours, tries to make contact
    with the wifi, sends a short message to the server, and then commits
    suicide and shuts the timer down again.

    Board designs all available if you want.

    Also source code, suitably modified to remove my wifi password

    At the far end is a Pi Zero with a very simple daemon running under
    inetd, to listen to the call and write the data to a file in a ramdisk.

    A web server then parses that data and calculates the oil level and
    displays it. (along with room temps and central heating states which it
    also controls)

    The intention is to run code under cron as well, and send warning emails.

    I may not bother to fix the DNS problem since it seems to resend the
    mail within the hours successfully.

    --
    No Apple devices were knowingly used in the preparation of this post.


    --- PyGate Linux v1.5
    * Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)