Radiacode + CYD (Cheap Yellow Display) - Part 2

Added: 2026-05-27

[00:00:00]All right. Today, I'm playing with these cheap yellow displays and what's left of an old power bank that I've got kicking around.

[00:00:08]These are incredibly nifty little things based on an ESP32.

[00:00:13]They have an SD card. They have speaker, a bunch of different IR ports, and a whole bunch of little options on here that are really handy, including an RGB LED, and even a light sensor on the top, and Wi-Fi and Bluetooth through the ESP32, and a touch screen. It's a little TFT 408 2.8-in screen.

[00:00:33]So, I've been in AutoCAD. We're going to make a case for it and see what we can do with it.

[00:00:38]>> [music] [music] [music] [music] >> Okay, we have some parts here.

[00:01:11]All right. So, now we have some 3-mil screws, 3-mil standoffs, and our tweezers.

[00:01:17]Let's see stuff fits.

[00:01:19]First off, the most important bit. These can go out of the way.

[00:01:24]This bit here. Now, we have a little square in here to put a little tactile switch, because when we assemble this, the reset and the main user switch are not going to be accessible. I'm going to piggyback a couple of thin wires off that.

[00:01:39]Put a button through the front.

[00:01:41]Next bit I'm interested in.

[00:01:44]How do we go measuring the screen?

[00:01:48]And will it fit in here? Oh, it's a very close.

[00:01:52]Oh, that ribbon cable on the bottom might be the probably the showstopper there.

[00:02:01]Take a look at the back.

[00:02:03]Um that's the piece there. That should drop in there.

[00:02:08]The holes look pretty good.

[00:02:11]So, this piece is going to sit nicely.

[00:02:13]Um these have all dropped in.

[00:02:15]So, that's good. That gives us our basis to bolt things down.

[00:02:19]Um [snorts] we want to check our next piece.

[00:02:24]Is this going to drop our in battery and bay?

[00:02:28]That's going to clip in nicely.

[00:02:30]So, that's going to work.

[00:02:32]So, that will be good. Now, is 6 mil enough to fit these in? A 6 mil looks like it is indeed enough.

[00:02:40]This will cover that. So, the battery bay looks like it's going to work well. So, the only real bit we've got a little bit of trouble with is one edge of this. So, let's see what I can do with that.

[00:02:50]All right. So, some manual adjustment later and a little bit of glass breakage in the corner later, we got it to fit.

[00:02:56]Should have just gone back out the shed and laser cut a new one, but let's see if it all goes together.

[00:03:02]All right. And uh the one thing I didn't bother to do is figure out how long the screws should be. They're one thread too short.

[00:03:09]But, I have threaded inserts. Whether or not they'll fit without breaking things is another matter.

[00:03:15]But, uh I guess I can always cut another back.

[00:03:20]Okay, we have things assembled.

[00:03:23]Little bit of broken in the corner, but I mean a cheap display, so we'll get another one.

[00:03:27]It's literally in the name. I have the two IO pins hanging out here.

[00:03:31]I'm hoping what I'm going to do with this is um we plug in here.

[00:03:38]But, uh what I'll probably do is program it up to use this button in here, which is now I think the super glue got into it.

[00:03:47]That's frustrating. I was hoping to use this button as the user button so that it can be shut it down.

[00:03:54]Um and then hopefully when it goes to low power state the battery bank under here will um shut down and go to sleep.

[00:04:03]Now, after all this, let's see if it actually works.

[00:04:08]Now, the button on here I think is a little bit in the wrong spot.

[00:04:13]Anyway.

[00:04:16]I tried to scan for something.

[00:04:19]Oh, okay. It's an auto connect if it only finds one.

[00:04:22]Okay, I forgot I programmed that and it just disconnected again.

[00:04:27]All right. Interesting.

[00:04:29]Um I might be using the user button that is now depressed in there.

[00:04:36]Okay, we got it disassembled, reassembled, we got the switch replaced.

[00:04:40]Yes, it will charge.

[00:04:43]I probably could have peeled that bit of tape off, but you know, that works so we know that will charge.

[00:04:48]We can unplug you.

[00:04:51]We can probably plug power in and make it fire up.

[00:04:59]Now, hopefully this will connect to the radio card zero. I probably need to refine the programming on this.

[00:05:06]I think I've got my position for that button out of whack.

[00:05:11]Let's see if it'll find the zero.

[00:05:14]It did and it's going to link. Let's see if it automatically disconnects cuz it shouldn't.

[00:05:19]Is it going to disconnect? Okay, so there's a problem with the code.

[00:05:22]We'll work on that later.

[00:05:23]The next morning. All right, it is the next morning.

[00:05:28]We got a cup of happening.

[00:05:30]Um we're going to address some programming.

[00:05:33]I am planning on using these as an access control for a radiation therapy um magnetic therapy machine.

[00:05:43]Not radiation cuz I'm looking at these.

[00:05:45]Um and we did test it around. It's got high voltage and magnetic shocks. We tested these to make sure they weren't going to die in that machine first.

[00:05:55]Um so, maybe we've done some damage to it in the process.

[00:06:00]Uh but, we've got to fix this boot looping problem.

[00:06:04]Or rather, the connection logging problem. Where is it?

[00:06:08]You know what? There we go.

[00:06:10]Now, at the moment it connects, disconnects, connects, disconnects, gets stuck in a loop. Could be power brownouts.

[00:06:16]Don't know, but we're going to try and fix the uh programming on that.

[00:06:20]Yeah, see? It's just going to disconnect and then go around a loop like that. So, we need to figure that out.

[00:06:25]Okay, we have it mostly stable now.

[00:06:28]We've figured that code out. We uh shoved some things across multiple cores.

[00:06:33]This should change um colors at 100 counts per second.

[00:06:38]Um if my samples in this container will get it there.

[00:06:41]We'll have to work that out.

[00:06:44]All right, let's test the big guns.

[00:06:47]This should for sure get us over 100.

[00:06:50]There we go. We should be able to get over 1,000 if I do it right.

[00:06:55]Yeah, shut up.

[00:06:57]There we go. I have a source a distance away, and I'm monitoring this from about probably 20 ft away. So, yes, it will go red at that high level. That's good.

[00:07:07]All right. So, I've got it to an acceptable state now, and I've got the power connection back into the power bank.

[00:07:13]I have set it to go to sleep, and I was hoping it would go to sleep and not re-trigger the um uh not re-trigger the battery bank, but it does when it uh the power bank turns off. But, the power bank fortunately has a little bypass button on here as well.

[00:07:29]So, I can just push and hold this, and I think it should wake it up.

[00:07:33]Should be keyword. There we go.

[00:07:36]That should turn it on. We've got the touchscreen working again.

[00:07:41]At least we did.

[00:07:42]But, I've got an override button just in case.

[00:07:46]The touch screen has some ghosting issues. It's picking up stuff that it shouldn't.

[00:07:51]But that's all right. We can just do this. For what I'm doing with this, this will be fine.

[00:07:56]Okay, we relocated this button around the side. We soldered it back onto the one there.

[00:08:01]Um the LED RGB LED in here should register different colors of things. I was hoping it would spread out a bit more than it does.

[00:08:09]But if I'm filming, which is what this is for, um you should be able to see a bit of light in low light conditions.

[00:08:16]It should sort of show through the back a little bit, although it's a bit overdriven by the blue lights from this, but I can probably do something about that. So, this is a good one. I'll see you in the next video and uh hopefully it's something interesting for you.