Canon CT-21

So, I like it. But there is some learning...

Colour

One aspect is setting colour options, and ensuring it knows the paper type, else you get too dark or too blue, or whatever. This is a general thing anyway with colour printing, but on my PRO-1000 I only printed on the same proper photo paper all the time, and so it always just worked. On the CT-21 I have a roll of A1+ "coated" paper. It needs slightly different settings.

Paper Size

This is where it gets fun...

The paper is A1+ width, i.e. 610mm (A1 is 594mm). Fair enough, it means you can print over size, and cut down with bleed over the edge of the print. The catch is you need a big cutter or are good are cutting against a straight edge.

Just to be clear, A1+ is not the max size, it will print up to 18m long from a roll - a banner, which is just crazy!

The print driver essentially allows basic size options, for example, for A1, it can be A1 with 5mm margins, A1 borderless, or A1 oversize borderless. The A1 is great if you are putting in a frame with more than 5mm edges. A1 borderless is great if the frame has little or no border, or if cutting to A1 exactly. Oversize A1 is great for that bleed over the edge, but still has margins of a few mm on the A1+ paper each side and at the ends of the print.

Then there is a "scale to borderless roll" which goes to around 609mm wide, a slight white edge each side. It also cuts the length in to the edge of the print by a few mm. This means you get an over size print with two cut edges and two very narrow white edges.

Confused? Well, yes, too many options.

What I did was make the oversize with print close as you can, and ended up with nice over size A1. The snag is they don't fit in the clip frames so needed cutting, on all four sides.

Now, it can, of course, do A2 on the same roll, sideways - well A2+ (all the same issues, just on the other two edges).

But A3 and smaller I can use the sheet feeder and plain or photo paper, etc. However it does not do borderless at all on the sheet feed, always at least 5mm borders, so a tad more limiting.

Three sided borderless

There is yet another option - 3 sided borderless, and I realise now that this is actually what I need to use.

It prints the image the size you selected, so typically A1 exactly (to then go in a frame, but no scaling or cropping involved from the original artwork). But prints it as far to one edge as it can, and then cuts the start and end. This means you have two cut edges, one very close to edge, and one margin. The margin means only having to cut (or fold over) that one side of four. This makes it very easy to put in a clip frame, or only one cut to use with no frame.

This also means I could print smaller sizes, A3, A4, etc. These are extra easy as the (now quite large) margin fits in my guillotine. It also means all the same (roll) paper with the same colour settings, and edge to edge, unlike using the sheet feeder.

This is an example of A1 three sided borderless - only one side needs cutting or folding over. This is 840mm left to right.

Some more of my videos

I have done a couple of videos on my circuit boards.

The fun one, I hope, is the "shopping channel" style one.

But also a more instructive one on making circuit boards.

And one on the Faikin boards specifically.

Canon PRO-1000 vs CT-21

I have had a Canon PRO-1000 for some time, it is an amazing printer. It is a must for someone producing professional photographic image prints. I cannot stress how good quality it is.

But I have just replaced with a Canon CT-21. So I felt it's worth explaining why, and what difference it makes.

Do I need a photo printer?

The first point is whether I need a photo printer. It is my only colour printer, and I do print photos for the family that get framed and go on walls, and so on. But I print stuff like a menu with a colour logo on it, etc, which seems overkill to use a PRO-1000.

Basically, I probably do not need a professional photo printer, really. It is just my usual overkill.

What is my use now?

Given the ability to print up to A2, I have actually been using it for posters for the pub. They are stunning.

Is A2 big enough?

The catch is, posters at a pub, may want more, like A1. So I decided to get the TC-21, which is an A1 poster printer that takes roll paper feed. If someone accidentally orders A0 clip frames at the pub, I may be in trouble.

What of TM-255?

I considered the TM-255 - it uses 5 inks, not 4, but has a base, and is just so big. It looks great, but I simply did not have space. The TC-21 fits on my bench. The ™-255 is also high volume and stupidly quick, but the TC-21 is not a problem for what I need in terms of print speed.

Key points in favour of the PRO-1000

• The photo print quality is just amazing, cannot be faulted.
• It does edge to edge printing on most paper sizes (oddly not A5), which is very cool. Even A2.

Key points in favour of TC-21

• It does A1+. Indeed, it will do 610mm wide and 18m long if you want!!!
• It does roll paper feed (which I am using for A1+ or A2+), but it can take narrower paper roll.
• It does sheet feed (no need to take out rolls feed, just manual sheet feed via top loader), all the way down to A6. Very handy.
• Easy colour refill - the PRO-1000 is easy, but this is only 4 inks.

Some downsides for PRO-1000

• It uses 12 inks, this is a feature in terms of quality but a pain in terms of costs and hassle with ink. It also gets through "maintenance kits" which also cost.
• If you do not use for a while, weeks, it will waste a lot of ink and take ages to start up. But it will then print perfectly. I don't know if the TC-21 does this.

Some downsides of the TC-21

• It is bigger, check dimensions, but wider by quite a bit. Well, obviously it has to be.
• It does not do edge to edge well - it can get very close on roll feed, maybe 1mm each side, and cut with no margin top/bottom. But not at all on sheet feed. This is perhaps its main lack of feature.
• It is only CMYK not 12 inks, but the photo printing is still good, and good enough by far for some family photos.

I do not know running costs yet, but the results are pretty good.

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.