Page 3 – Hermetry

Posted January 28, 2026 at 8:27 pm · in Putting my ESP32 sensors on their own network: what do they need to reach? #2

Does the AX55 let you set firewall rules per network, or only the guest on/off isolation switch?

Posted January 26, 2026 at 6:12 am · in After a pip upgrade the chiller script on our Pi dies with an “Unsupported callback API version” error #7

Worth putting the versions in a requirements.txt next to the script so the next upgrade doesn’t surprise anyone.

Posted December 19, 2025 at 10:28 pm · in Wiring Grove sensors straight to a board, no Base Shield #4

The shield is for Uno-shaped boards, the ESP32 DevKit doesn’t plug in.

Posted December 19, 2025 at 10:57 am · in Counting vends on the office drinks machine: send each vend or a running total? #2

Whatever you do, debounce the microswitch. A can bouncing down a chute will give you 3 counts.

Posted December 6, 2025 at 7:34 pm · in After a pip upgrade the chiller script on our Pi dies with an “Unsupported callback API version” error #2

Which paho version is on there now? pip show paho-mqtt

Posted October 26, 2025 at 2:34 am · in Pushing our own firmware over the air to trackers built on a pre-certified LTE-M module #5

Lab confirmed by email: application updates within the grant are fine, they added a note to our file. First wave of 10 went through yesterday on LTE (allowed only for those 10). One failed with a signature error because our build script signed the debug image, bootloader refused it as it should. That alone made the setup worth it.

Posted October 22, 2025 at 3:58 am · in Pushing our own firmware over the air to trackers built on a pre-certified LTE-M module #3

Only our application on the host MCU, the modem firmware is the vendor’s and we don’t touch TX power or bands. Antenna is the reference one from the module’s grant.

Posted October 19, 2025 at 8:12 pm · in Pi 4 shows 52 degrees, which is the CPU. How do I read the room temperature and send it up? #5

Also don’t feed it 5V. The data line gets pulled up to whatever you power it from, and the Pi’s GPIO pins are 3.3V only.

Posted October 3, 2025 at 8:03 pm · in Tutorial says broker = 192.168.x.x – what address do I put in for Hermetry? #2

What exactly does the Connection details card on the device show you? Host and port?

Posted September 12, 2025 at 10:01 pm · in Pi Zero + SIM7600 trailer tracker drains a 10 Ah power bank in nine hours #2

What are the GPS and the modem doing between fixes? Both on all the time?

Posted September 11, 2025 at 7:18 pm · in No screen, no keypad: getting Wi-Fi and a token onto 12 ESP32-C3 lab nodes #4

WPS? Hold BOOT for 3 s, press the button on the router, done. Did that on some warehouse scanners years ago.

Posted September 8, 2025 at 1:03 am · in Cheap way to drive a 700 mA LED that I dim from a board slider #6

PT4115 module in, two bucks each, PWM at 1 kHz into DIM. No more hot resistor and the brightness stays put. Slider works with Ask before running off, level comes back as light.level. Thanks David.

Posted September 2, 2025 at 12:00 am · in ESP8266 logger that is offline half the time: where do I get the time from? #4

One gotcha with the DS3231 boards: the cheap ones have a charging circuit for the coin cell that you should remove if you use a CR2032.

Posted August 9, 2025 at 7:13 pm · in Clicking a gate symbol: should the drive run in position, velocity or torque mode? #4

Rebuilt it as position mode with gate.move open/closed and the drive’s own limits. Did the double click test on purpose, it just goes to open once. Symbol follows the reported position now. Thanks Ciaran, and Aoife, torque mode had me thinking for a minute.

Posted August 7, 2025 at 7:32 pm · in Cheap way to drive a 700 mA LED that I dim from a board slider #4

Dimming, the night shift wants it lower. 0 to 100 on the slider.

jason_fw

Forum Replies Created