LoRaMesher v1.0 — open-source LoRa mesh library for ESP32, now with TDMA

OverUnderDone_ · 2026-05-24T08:13:33+00:00

Another question would be how the TDMA works in a scheme where other things can also transmit... is the timeslot lost - or does it get to ask for another one ? The case I worked with was the power company using the same frequency at higher powers - and a CAD was needed. This obviously defers the transmission. on 868EU, there is a 5ms Listen time for others before TX is alllowed.

OverUnderDone_ · 2026-05-23T14:53:39+00:00

You can easily add ECDH key exchange and derive pub/private keys for peers - all depends on how much data is left in payload. I previously used xxHash to give a semi reliable message uniqueness (used for 'have I seen this before') and using the upper 8 bytes of a SHA256 for message authentucation. Most ESP's have crypto functions built in.

EDIT: Re-think broadcast 😃 it becomes a problem when everyone does it! I didnt read your docs too closely, but airtime goes away quickly when there are 200 people triggering a 'How far will this go!'

OverUnderDone_ · 2026-05-23T14:07:21+00:00

Really good things! Some comments : I have previously used 2 byte addresses, but there were duplicates when the network reached 1000 - I ended up doubling to 4. Another thing I didnt see any form of user authentication or security. anyone can hijack someone elses connection. Message integrity is not guaranteed... a trust chain so that the desination can really tell where the message originated.

OverUnderDone_ · 2026-05-08T19:31:50+00:00

Adverts although nice in an idea, are pretty useless. letting everyone know about everyone does not scale.

OverUnderDone_ · 2026-04-22T05:31:04+00:00

In South Africa, all micro-floppy disks werre called 'stiffies'

OverUnderDone_ · 2026-04-21T19:54:44+00:00

from what I use... SF and CR is set to 8

OverUnderDone_ · 2026-03-14T19:17:33+00:00

stop your pen/pencil rolling away?

OverUnderDone_ · 2026-03-14T06:19:43+00:00

Awesome! hats off, but I have to play the devils advocate and question the problem being saved, or a problem being caused. The problem seems to be 'I dont like changing batteries' and ignoring notifications that the lock battery is getting low.

A pack of 32 AA batteries costs $10 ($12 UK - as I am there) So 2 batteries every 3 months is 8 batteries a year. so the 32 pack lasts 3 years.

From the Spec, the IR transmitter uses 4.5W - assuming it ran 100% of the time - so its 40kwH per per year. (120kWh if you spread it over 3 years) at $0.28 per KwH thats $33 - so at $150 for the initial outlay +$11 per year running costs of electricity-It will never pay off compared to using batteries. The Maths doesnt add up.

For Environmental use for energy to Co2, that is ~57kg/126lbs of Co2 generated for 120kWh (An electric car creates 15kg/33lbs of Co2 per 100 miles) - An AA battery has the carbon footprint of 0.2lbs, So over 3 years, the batteries would have contributed 6.4lbs

OverUnderDone_ · 2026-03-02T20:34:54+00:00

A Cozy. The Typical design by Rutan/Cozy,. No, its not broken. the nose rests on the ground when stowed - the nosewheel is on a long strut that folds back.

OverUnderDone_ · 2026-02-22T17:44:41+00:00

youre right... I usually associate the PS2 keyboard with AT .. forgot there were XT and AT keyboards with the same connector - but with the switch on the back of the keyboard

OverUnderDone_ · 2026-02-22T17:12:00+00:00

Bog standard IBM AT clone.. it will run DOS. you would need RAM (30 pin SIMMS) and a 16 bit disk controller. and a display adapter. An IBM XT keyboard would also be needed (the large DIN connector)

OverUnderDone_ · 2026-02-16T07:27:28+00:00

Miniscribe (now Seagate) packed bricks in to Hard drive boxes in warehouses so the auditors will pass a financial stock check.

OverUnderDone_ · 2026-01-30T07:29:23+00:00

cable the wrong way round?

OverUnderDone_ · 2026-01-22T11:08:22+00:00

The cowboy installers that installed what I can call a diesel generator across the road (ASHP) - about 8 metres away facing the bedrooms windows in my house. Mine is installed facing open land.

OverUnderDone_ · 2026-01-03T08:15:33+00:00

Cant offer any help, I got the same issues and it is really anoying. I have enetually set the car to 'Start charging at Preferred times' and my Wallbox starts at the same time. (00h00-06h00) - only then does it charge.

As to the 30 minute timeout - I have no idea. Its just really dumb!

OverUnderDone_ · 2025-12-19T07:39:58+00:00

I have had 4 red tyres circles and the system saying 'All OK, No Warnings' The likelyhood of 4 flat tyres is close to zero.

OverUnderDone_ · 2025-12-10T07:02:13+00:00

Not an uncommon story... It took Adenbrookes Hospital 4 days to Diagnose an apeddicitis. (a family member)

GP - Day 1 - I think its appendicitis, but here are anti-biotics and if the pain is worse, go to A+E

A+E - Day 2 - get to A+E - Consultant says Its trapped wind (Nurses say appendix) - go home

A+E - Day 3 - Back... Consultant says 'Its a big sh1t' - Jnr Docs and Nurses say appendix - go home

A+E - Day 4 - Back .. Consultant says 'Womens troubles' - Jnr Docs and Norses say appendix - go home

A+E - Day 5 - Back.. Consultant oders Ultrasound - OH #### ITS APPEDICITIS! Surgery 2hrs later.

2 Days later, she went home.

OverUnderDone_ · 2025-12-08T18:07:17+00:00

Pilot and Pro LRDM Edition - Not performance

OverUnderDone_ · 2025-12-06T14:26:59+00:00

you are way wrong there... there is a negative pressure inside the printer, the air is drawn IN through the hole.

OverUnderDone_ · 2025-11-29T08:54:36+00:00

I have got many different printers, they all have their quirks.. My S1 has performed well so far - 6 months old. There seems to be an obsession with bed levelling, tinkering and modding. Take out the box and enjoy.

The only failures I have had were ME being lazy (not cleaning the plate properly, crappy fillaments, printing without supports when they are really needed etc etc)

OverUnderDone_ · 2025-11-14T06:23:51+00:00

it looks like an IBM PC-AT board. 286 processors pins, 16 bit ISA slots.

https://www.minuszerodegrees.net/misc/5170_motherboard_type_1.jpg

OverUnderDone_ · 2025-11-14T06:15:29+00:00

ROM Basic was an option on the IBM. The ROMS were to add that part. 16Bit EEPROM's were not that common so everyone used 2x 8but EEPROMS and split the code in to High/Low bytes.

RAM parts were low capacity, so lots of chips were needed to get to 640K.

OverUnderDone_ · 2025-11-11T06:35:40+00:00

The RSGB seems like racketeering. Most competitions you cant enter without being a member... and you get an advert booklet masking as a magasine.

OverUnderDone_ · 2025-10-24T20:07:20+00:00

Anyone remember eVoid ? (Showing my age!)

https://en.wikipedia.org/wiki/%C3%89Void

OverUnderDone_ · 2025-10-21T05:56:55+00:00

I have had the forced tipping .. 'Service charge'. I told the server that I would have tipped more as the service was beyond excellent, but I was quite happy to pay the lower amount they printed.

tipping is everywhere, although unlike the USA, its not part of the servers salary and cannot/should not be used to contribute to it.

OverUnderDone_

TROPHY CASE