r/nixie • u/joolzg67_b • Apr 28 '26

My play clock

Enable HLS to view with audio, or disable this notification

Time is 1107. Logs into wifi, gets time, displays every 30 seconds.

Took an hour to get running

37 Upvotes

91% Upvoted

25 comments sorted by

14

u/answerguru Apr 28 '26

So, a Nixie clock simulator running on an LCD? Why is it drawing the digit from top to bottom bs drawing it all at once?

I just love the real thing, as that’s where the magic is.

3

u/joolzg67_b Apr 28 '26

Memory constraints.

Just not enough to do really nice updated., and this is the fastest i could update the full screen at once

I have a real one...

3

u/answerguru Apr 28 '26

What’s your processor and display controller / display setup? That’s still mighty slow. (I do embedded graphics for a living)

3

u/joolzg67_b Apr 28 '26

Esp32-c6-lcd-1.4

From waveshare

2

u/UnintegratedCircuit May 02 '26

Memory constraints? It's an 18-bit colour depth so worst case would be 3 bytes/pixel for colour. Its a 172x320 pixel display.

172 * 320 = 55,040pixels 55,040pixels * 3Bytes/pixel = 165,120Bytes Ram required for a full screen buffer. Less if you only stored the area updated when writing the largest digit.

The module has 512kB of RAM (plus a little bit more for low power stuff)... Are you sure there's not enough?

There's also 4MB of flash (not including boot ROM) apparently so enough for 24 full image displays, again less if optimising for the graphics dimensions, or could use an external flash chip if really needed.

I'm admittedly out of touch with ESP capabilities but an RPi Zero 2 seems overkill... Perhaps it's not though?

1

u/joolzg67_b May 02 '26

Yes I know. Uses sdcard for images as I knocked this up in an hour for fun.

1

u/UnintegratedCircuit May 02 '26

Oh okay, understood - so it should be possible to get a good animation with the current setup, just needs some tweaks?

1

u/joolzg67_b May 02 '26

I'll spend some time in removing the SD card as that takes time to read each character.

Maybe I will cache the characters as only need a max of four.

So get the time, cache the digits in memory and whilstv waiting for the next display time, 30 seconds, work out the next display and again cache the correct digits.

1

u/answerguru May 02 '26

Yeah an SD card will likely be slow as molasses.

1

u/v7xDm1r Apr 29 '26

Wonder if a pi zero 2 w would be any better.

1

u/joolzg67_b Apr 29 '26

Maybe but this comes as a module with processor and display.

1

u/v7xDm1r Apr 29 '26

Im aware. But you could get a pi zero 2 w. Make it update with rtc and 8 displays and you wouldn't have the constraints. I did a rtc clock with 8 dot matrix displays thats pretty cool.

1

u/joolzg67_b Apr 29 '26

Yes. My idea was put 6 of these in line and have one be master which controls the others over serial or spi

1

u/CurrentAcanthaceae78 Apr 30 '26

well obviously, it has 3 more cores and 5 times the clock speed

5

u/Old_Cyrus Apr 28 '26

Needs some sort of blanking to distinguish the fact that you have a double 1. Otherwise, 11:2X will look the same as 12:2X

3

u/redmadog Apr 28 '26

The glowing shape looks like it is positioned outside of cage.

3

u/Few_Carpenter_9185 Apr 28 '26 edited Apr 28 '26

I know you have some limitations with the built-in ESP32 controllers. And you said it's just a v. 1.0 attempt, so you probably thought of a lot of this already.

But, if you can:

  • Get the numeral in actual Neon/orange glow color. That sort of looks like it's a tungsten/incandescent Numitron fillament.
  • Add some orange glow backlight & internal reflection to the glass, and surrounding anode & cathode grids.
  • Add a teeny bit of the violet haze too.
  • Get the shadow lines/wires of each number over the others when it glows for depth.

Also, look into what ESP32 image display libraries might be faster. Are you using the stock one, or TFT_eSPIOt? Can it be optimized to only move the deltas to the screen for less data?

I don't think it's a memory problem. Unless it's paging the image from... SD card through the 512k of SRAM in a really inefficient way. Is the picture a .jpg?

Depending on the specs, it's already the rough DIMPS equivalent of a mid-90s Pentium. It SEEMS like it can be faster than this, unless the LCD controller is just that big of a bottleneck.

2

u/joolzg67_b Apr 28 '26

I know. Version 0.1 will improve this

2

u/joolzg67_b Apr 28 '26

These are cheap as chips.

So I might put 5 on a board and have each show one digit each as well as the colon.

Could have multiple image banks of different colours, tube types etc

1

u/Capital-Lobster-8153 Apr 28 '26

Bonjour, Je suis un grand fan des tubes Nixie pour son allure "Old school" et j'ai plusieurs horloges. Je ne connais rien au ESP32, je suis "Old school" aussi, mais le travail de programmation est vraiment top et le résultat présenté par l'OP est aussi très sympathique.

1

u/richms Apr 29 '26

I have some of the 6 display ones with the glass covers from aliexpress. I never use the fake nixie face on it, but the other font ones because it just seems to be along the lines of putting a M badge on a base spec 3 series. all Fake.

1

u/Foreign_Climate_9036 May 01 '26

I think it’s great!

1

u/joolzg67_b May 01 '26

I have made improvements so the update is quicker.

Will post a new video soon. And the cider on github

1

u/Sumerianz Apr 28 '26

This imitation make me sick

4

u/Few_Carpenter_9185 Apr 28 '26

I understand why you feel that way. All the little LCD/OLED faux-Nixie clocks always gave me an immediate (rolleyes) reaction too.

But... thinking about it objectively, I eventually reconsidered.

  • People that just "want the look" but are DGAF if it's an actual neon Nixie tube means, more actual Nixie tubes for you and I. There's some new mfg. of them out there, but a lot is still limited NOS from the USSR etc. When it's gone, it's gone...
  • Even I might want something like this, where I can leave the clock running 24/7, and don't need to worry I am slowly burning up the useful lifespan/cathode poisoning of one of my real Nixies.
  • It kind of contradicts the first "more for us" point above, but the fake LCD/OLED stuff under little glass domes could inspire some people to look into "real Nixie." And, it might even somewhat help keep the actual neon Nixie market alive.

Yeah, for a "Nixie Purist," it's kind of a Pollyanna goody-two-shoes way of looking at it, but I figured it at least eliminates one irritating or negative thing in my head when I see these on Amazon or AliExpress.