maybe… @ the moment they are on a local nas and in the cloud, didn’t researched a lot last weeks but yeah, maybe google is an idea too tnx
new e paper portable test rig next to the ‘old’ one 
these e paper displays are a perfect match for let’s say a temperature node.
they don’t use any energy so the last measurement transmitted stays on the screen after you disconnect the power (gpio off) and the processor goes to sleep.
the display flashing during write (always full screen and can take up 1 to 5 sec!) is no problem when refreshing a few times per hour .
problems arise when you try to partial write (then you don’t have that flashing) something (updating a value) the screen looks then like its is in a snowstorm, gone is the beautifull white background.
@ the moment I’m trying to make a menu with a rotary… menu’s are 99.9% of the time static so theoretically a good candidate for epaper , if you don’t turn a knob or a switch it uses no energy.
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Portable you say?
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ghostbusters ?
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No hunting for rogue LoRaWAN nodes
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very nice 
Very nice
Hello All
Im from Jakarta, Indonesia
So much insteresting topic, thank you all for sharing, so many interesting ideas
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what filament do you use? it is wheather shield?
Where i can buy this module?
Hi Charles, these tyraps will get ‘brittle’ after a while and break (been there )
To be safe fit new ones once a year
- there are Stainless Steel Ty-Raps but expensive
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Whatever it does, it at least looks interesting. 
(even spotted a STM32 bluepill)
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connecting an 8 position pole switch to I2C with the help of
PCF8574 (8 position) or MCP23017 ( 2 x 8 position)
MCP23017 :
- https://github.com/adafruit/Adafruit-MCP23017-Arduino-Library
- http://learning.grobotronics.com/2013/07/ger-extra-16-lines-of-io-with-mcp23017/
- https://github.com/rambo/mcp23017/blob/master/examples/mcp23017bounce/mcp23017bounce.ino
- https://www.ebay.com/itm/MCP23017-DIP-SOP-Bidirectional-16-Bit-I-O-Expander-I2C-IIC-Serial-Interface/382397212438
PCF8574 :
my virtual design is almost done… just a couple of weeks more
So I am looking for a small board to battery-power my nodes.
Perhaps this will do:
http://www.icstation.com/lithium-battery-charge-discharge-protection-integration-board-boost-voltage-module-p-8996.html
Previously tried this one:
https://nl.aliexpress.com/item/DC-5V-2-1A-USP-Mobile-Power-Diy-Board-4-2V-Charge-Discharger-boost-battery-protection/32824032545.html
But that has no discharge protection and as a result over-drains the battery.
Any other suggestions?
there exist also 'protected ’ 18650 battery’s, they have a build in protection circuit.
but think of this… when you drain the battery without protection, the MCU brownout will normally shut down the circuit 
also I don’t trust these ‘protection’ circuits from the cheap dc/dc boards… 9 out of 10 don’t work as they advertise.
what you can do is measure (once a day ?) just after Tx the voltage of the battery and send an alarm byte when it’s getting to low.
Most of these ‘protected’ batteries and circuits can let the battery go as low as 2.4V.
I am not convinced its a good idea to let a Lithium battery repeatadly go this low …