IR LED controllers

I ordered a couple of LED controller remotes.

Now to work out how they work.

The first (big one) is simple 32 bit NEC coded (i.e. address, inverted address, code, inverted code) with address 00. Laid out as follows for the code:-

5C 5D 41 40

58 59 45 44

54 55 49 48

50 51 4D 4C

1C 1D 1E 1F

18 19 1A 1B

14 15 16 17

10 11 12 13

0C 0D 0E 0F

08 09 0A 0B

04 05 06 07

As you see, this has some pattern to it, but why not literally a proper grid or sequence, why this. But OK, I can cope. I plan to make my LED controller boards have IR receivers and understand this in some sane way - with extra keys like DIY1 do device automation to Home Assistant.

But what of the smaller one?

Well this is special, it is 32 bits, just like an NEC remote, but the first bytes are 00 EF not address and inverted address. I mean, it is distinctive, and consistent on all keys, but not quite standard. The code is still code and inverted code though. The codes are then:

00 01 02 03

04 05 06 07

08 09 0A 0B

0C 0D 0E 0F

10 11 12 13

14 15 16 17

This is way more logical key codes.

Simpler

For completeness, this is a nice simple IR from Amazon.

Which is address 00 and codes:

45 46 47

44 40 43

07 15 09

16 19 0D

   18

08 1C 5A

   52

Which, as you can see, is all over the place! 

Infra-red remote conrols

I have done a lot of stuff over the years, and the "old" tech, like barcodes, and modems, faxes, and all sorts have not passed me by, even old school "light pen" on a BBC micro.

But somehow one "old" tech passed me by somehow, and I am not sure how - the IR Remote.

They are a lot like barcodes, but without the variable timings. They are simple, and why the hell, in the last 50 years, have I never played with IR remotes? Mad.

So I have started.

This is my environmental board, and apart from light, sound, pressure, temp, humidity and CO₂ sensors, it has an IR receiver. So I had a play.

The ESP32 has built in IR receiver (RMT) hardware that logs timings for the on/off from the IR receiver modules (which handles the 38kHz modulation for me).

It is a doddle to decode - actually way easier than barcodes. So I have decoded the very common NEC format, and the remote for the Daikin air-con.

NEC

The NEC coding is simple - a long/short header, and then pulse distance coding of 32 bits. It is 4 bytes (and annoyingly low bit first) which are address, and inverted address, and code, and inverted code, making a checked 16 bit sequence of fixed time duration.

This seems to cover a variety of bog standards remotes, like TV remotes. Interestingly my LG TV remote only does IR when the TV is off. Once on, it uses something else (not sure if bluetooth or what). It uses address 04.

I also have a very generic IR remote from Amazon, which is address code 00, and several (very illogically mapped) codes.

A single bit code 0, with a different timing header burst, is repeated whilst the button is pressed. Easy to decode press, hold, release.

Daikin

The Daikin remote is more complex, some 8 byte sequences, and a 19 bytes sequence, sent every time, using a simple byte checksum code at the end. Again, pulse distance coding. But again not hard to decode.

More

I have some more IR remotes coming to play with. So we'll see how they work.

Evolution of my code and PCBs

One the last few weeks my code and PCB designs have evolved a bit!

EPD

This is still called EPD (E-Paper Display), but in practice it is now a general purpose signage system allowing a number of widgets to be displayed getting data from many sources. Making it work with the 2" and 2.4" waveshare LCDs was nice. I got my PNG code doing colour nicely for this, and alpha blending.

One aspect I was very pleased about was the display connection - the display has 8 pads/holes at 0.1" spacing for a normal 0.1" header pin strip. Making a board to work with this is easy and you solder top and bottom - done! But it makes it almost impossible to remove cleanly if ever needed.

The trick is a surface mount header on my board, on top of pads/holes to allow for longer pins. This then allows 0.1" header pins on the display that then just plug in. It can be unplugged simply if access needed for connectors, or if changing display/board at any point. 

But the code has evolved even more - allowing a wide number of sensors (I2C and one-wire-bus), and formatting specially for temperatures (small C/F, colour based on range), etc. And now even BLE based temperature and humidity sensors as well.

In fact, with all of the sensors reporting to Home Assistant, I have had to make a "non display" version of the code for someone that is using this with no display - which is crazy for code designed to display stuff.

I also added handing of buttons as the board (see below) has them, causing Home Assistant triggers.

Faikin Remote

This other code has worked very much in parallel with a lot in common - including adding a load of sensors, the same as EPD. The main use case is to work a Faikin.

However the PCB design for this has ended up being a key module for use with my EPD code. It too has changed.

The initial sensors were temperature (as main thing for Faikin remote), humidity, and CO₂. The module is designed to also work a fan and radiator based - fan based on humidity and CO₂, and radiator based on temperature for cases where you have air-con and radiator. But it works for rooms I have that only have radiator, obviously. So it is an environmental monitor (working with HA) and a remote for the Faikin.

It also has pressure, so the CO₂ can be calibrated, and a light sensor so it can go off when dark (ideal for a bedroom).

But it is growing, with my latest designs (not yet on sale) having a microphone for noise level, and also an IR remote receiver. The idea of the IR is that a Daikin remote could work this directly. I'll need to code these soon.

It is becoming a really comprehensive environmental monitoring board now.

I was also asked to make the snap off bits (button, CO₂, and now IR) have pads to allow them to be wired in, so that is done - you can remove and mount nearby and wire back to the board.

Practical uses

Obviously I have these working with Faikin modules, and have them working with radiators (with and without air-con), and in places just monitoring. Some customers have them around offices to monitor workspace environmental conditions.

One good use case with remote BLE sensors is the pub. Showing BLE sensors in various places, and the DS18B20 temperature probe from another of the boards in the cellar monitoring the beer cooler. The fact this is all visible from the bar now makes life easier, and highlights any out of temperature readings (like when someone opened the beer keg store room to put in a sensor).

What is ideal is this is all reported and logged and graphed on Home Assistant as well. Any issues with the beer/lager the bar staff can see if there is an issue with the cooler at a glance (as had happened a couple of times). We also have logs and graphs which helps when the engineer comes in to sort the cooler.

Next step is probably one monitoring all the fridges. I found these small BLE sensors manage to work inside a metal fridge, if you are close enough. They will still do their temp checks, but this will alert quickly in one place if any issues, and provide historical records nicely. Obviously we check these with a calibrated thermometer as well.

All I need to do now is find a source of the BLE sensors that still work and can be flashed with Telink Flasher. Any pointers welcome.

Tindie

Yes, the code and PCB design is all open source, and I have these on Tindie. I do a tad cheaper for collection from Aber if you are local. Check it out as there is quite a lot on there now.

Finding customers

I have the Tindie store set up now. But no good way to promote as yet. My problem is I generally hate the whole advertising industry (as a consumer). This leaves me a tad stuck on how to make people that actually want the products even know they exist. Of course, being that selective (a) avoids annoying people that do not want this, and (b) is highly targeted adverts which I, and others, hate even more, arrrg! You can't win.

A blog post like this will help, I am sure, but even this feels wrong, it is an advert on my blog, which is not that fair really - you did not come here for adverts, did you?

What is fun is I have a few customers (they are actually local, so collect, and do not buy on Tindie, so cheaper), but they sort of self identify as addicts of my tech. I really appreciate their business and feedback and suggestions. I just wish I could find a few more addicts :-)

So I'm interested in the most ethical ways to promote these products - suggestions welcome.

Scammer energy calls

So a friend got a call when I was around and so overheard I heard much of it (she was quite happy that I did), and then hopefully I have reassured her that it was indeed a scam.

But it is hard work.

They somehow claimed to be from her energy company, now I did not hear the start exactly, i.e. if she gave away the name of the company or they knew/guessed.

The gist of the call was simple, they were supposedly over due paying, and would be cut off tomorrow (Sunday). The caller claimed they had stopped a direct debit, and were now £6000 in arrears, which had to be paid.

Now my friend was not totally stupid, she asked them to confirm the customer number, and they did. That is the scary bit. Now, I have no idea if energy companies have some system allowing details for things like that for take overs and so or that allow this information to be obtained, or if, perhaps, previously they had managed a call and extracted this, or a data leak or what. But she did what seems to be a very reasonable check.

The problem is, and this is where scammers have a good chance of something like this, there is an issue with the smart meter not reporting properly, and so they have done estimated bills and been told readings. Sadly this is what makes the scam more plausible - months of estimated readings could be a sudden surprise bill.

This was very upsetting, but she said to email the statement please. She did not go for the pay over the phone so as to avoid being cut off next day. One of the main reasons she did not fall for it is that the scammers did not know that £6000 was, in this case, implausible. Had it been electricity not gas, maybe, but no way for gas in their case.

Now, checking carefully - step one, googling the CLI says SCAMMER, which is a clue.

Checking on-line energy bill accounts, DDs working, last DD a couple of days ago, no outstanding balance. Yes, estimated readings but checking and they are actually within around £10 of reality. So clearly a scam. Also a tad unlikely coming to cut off on a Sunday, and a tad unlikely an overdue account without any statements or demands first.

But some people would have been fooled. Indeed, had it been a few hundred, my friend may have been, even.

I am, however, surprised such scams work - how do they get the money? A card payment could be clawed back, surely. A bank transfer would not match the name or the known bank details. How do scammers actually make money out of this?

So watch out there please.

Laws

When I was growing up, I learned that there were laws.

These were not simply rules or views of people like my parents or teachers, but something more. Laws were things that somehow defined the moral, and immutable set of rules for life. If you broke laws there were police that would take you away and lock you up.

Over time one realises that laws are not quite so concrete. For a start, they change, and new laws come in and old laws are repealed or changed.

The idea that something today may be illegal tomorrow, or the other way around, is crazy. It is how it works, but that is, well, just mental, how can a thing change from "right" to "wrong" or "wrong" to "right" just because we have moved on in time?

What I later learned is that these laws we all follow are created by, well, just people. And they are not people that have a lot of training, and learning, and credentials, and academic achievement or qualifications in their field. They are created by people that happened to win a local popularity contest in their constituency, working with others that have the same credibility. There is no qualification needed to make laws. There is no test. There is no exam. You literally have to win a local popularity contest to be an MP, and MPs can literally make new laws.

That, in itself, in insane, sorry. I mean some of them are sensible, and some even qualified. I have known some MPs that seriously know what they are doing. But "running the country" and, importantly, "making laws" has no qualifications needed. It is amateurs that won a local popularity contest, that is it.

So is there a better system?

Environmental monitoring

The new Faikin Remote have sold a few, nice. Thank you. Now on Tindie, and more coming soon. The BLE linking to Faikin is working really well now.

But ironically more have sold not as Faikin Remote, so far, but as environmental monitors. The boards have pressure, temperature (via many means), humidity, and CO₂.

What is even more amusing is that the monitoring is probably best done using my generic display signage code (EPD) as it has all the sensor code to allow display of the values. No link to Faikin, but links to Home Assistant, and simple http polling, and so on, for all sensors.

Irony on top of that is I have had to just make a version of my display code for no display, a blind version, as it is ideal for this monitoring application even when you have no display (data centres, etc).

Home and office monitoring of CO₂ levels is becoming more important as people realise how much of an impact a lack of fresh air really has.