Stephen and Parker talk about teddy bears, Raspberry Pi LVDS, and relays that last till the end of time.
Podcast Transcript
Host 2
Hello, and welcome to the macro fab engineering podcast. This is Episode 61, where your hosts Parker Dolan,
Host 3
and Steven Craig. So we would love to hear from our listeners, tell us what you think your current projects, any topics you want to cover, or just say hello. To reach us, follow us on Twitter at macro fab, or send us an email at podcast at macro fab.com. Also, if you enjoy the podcast, please tell a friend coworker a loved one or just tweet it out.
Host 2
If you send this to your loved one. You might not love them.
Host 3
So we we have some cool stuff coming up. We have some koozies to give away to our listeners for some macro macro swag. Yeah, macro swag. So if you send us an email with the code word that we will mention, during the show, you can you can get a koozie
Host 2
or just send us an email.
Host 3
So yeah, keep keep your ears out for a code word.
Host 2
Host 3
Host 2
So What's something else? I didn't actually write it on the sheet. So it's not your fault. Oh, the event that we're having here in Houston?
Host 3
Oh, yeah. Yeah. The meetup. Yeah,
Host 2
it's at the end of May, right. Yes, yes. I don't remember the dates.
Host 3
Yeah, you're right. You're right.
Host 2
Wait, no, no, April. It's at the end
Host 3
of April. Dead silence. That's right. Chris
Host 2
Host 3
we're on top of the ball here. No.
Host 2
Computer phone saved us again. Okay,
Host 3
engineering makeup at at not makeup meetup at macro fab.
Host 2
I think if an engineer tried to put on makeup and not go to good,
Host 3
or just be like really blocky and like really perfect, in really symmetric and look terrible.
Host 2
Probably. I don't know anything about makeup.
Host 3
Okay, anyways, yeah. So what's been up, Parker?
Host 2
Um, so I talked about last time, we didn't have a guest. It was the spooky pinball, a low voltage differential signal controller thingy for the Raspberry Pi. So that's all working? If what does that do? So what it does is it takes the display parallel interface on the Raspberry Pi, and basically converts it to LVTs, which is low voltage differential signaling, which you can pass to a display an LCD display that you would find in like a laptop.
Host 3
Okay, so the data converter, sort of kind of
Host 2
Yeah, it's a parallel to serial converter. And also level shifter, because you're converting the TTL level, which is like 3.3 volts to basically OBD S, which is like 1.5 volts, a 2.4 volts, something like that, right?
Host 3
It's something like that. Yeah.
Host 2
Because it stays within those two voltage ranges. That's why, right, but
Host 3
you're also turning it into a differential signal.
Host 2
That that, that's why I just said, great differential signal. Yeah, but serializing it too. Right? Yeah, you're taking a so data conversion, you take a six bit, basically red, green, blue parallel bus, and converting that into a six bit long serial stream that outputs right. And it's pretty cool. Because you basically just give it all your data, and then you give it their H sync and V sync pulses. And that chip, just magically does it. It's actually pretty sweet.
Host 3
So it makes writing your firmware pretty easy.
Host 2
Yeah. Well, it depends on what you're driving it with. With the Raspberry Pi, it's got this cool feature, I guess kind of you basically can get really low down and tell the basically the GPU what timings to use to draw the interface. So you basically open up the datasheet for the LCD screen and read the front porch, back porch for all the signals. He tells the resolution the clock cycle, how long the pulses are. And basically you write that out in one big config line. And then when the PI boots up, it reads it in and goes That's what I should do, and does it. Okay, so it's even easier. Yeah, it's actually it took me less than one hour to get this working. Wow. Yeah, that's certainly longer delay the board out in the boardroom. It has like 20 parts or whatever on it.
Host 3
Well, and this little board you made, it's basically just a power supply and this one chip.
Host 2
Yeah, it's got a five volt regulator and a 3.3 volt regulator to basically dump 12 volts in because the screen needs the backlight. Power up. The only thing this board doesn't do yet, is PWM The backlight LCD can't change the brain. So it's max brightness. And I don't know how I want to do that yet. Because I don't know if I can use the hardware pins on the Raspberry Pi to PWM it or it's not gonna be fast enough. It's also how do you control that do try to control that through like the keyboard API. I got to look more into that if you know how to control like, like, you know, like the function keys on my laptop keyboard. Yeah, that's kind of what I want to do. I want to be able to bind a key function to adjust a PWM frequency on a pin out of Raspberry Pi.
Host 3
Oh, I guarantee you one of our listeners has like that already written.
Host 2
Yeah. So let me know. Um, so yeah, the the actual chip is the TI DS 90 C 365. A pretty awesome chip it's pretty low costs for and it does what a couple bucks and quantity it's like two bucks. Okay. I think it's like four or something and singles. But yeah,
Host 3
what kind of package is it in?
Host 2
T SOP so point four millimeter
Host 3
how many pins 40 Okay, so I hand soldered I was just about to say you could hand solder if you want to Yes, I
Host 2
I think point four millimeter T Sophos relatively easy to hand solder with a microscope with a microscope. Yeah, actually, I did these without a microscope. Whoo. Yeah, I was using a hot plate. And I the heat the because it's a four layer board. So I wanted to heat the ground plane up pretty good. And then it just flowed like butter. Well, liquidy metal butter. Like, Terminator style, I guess T 1000. T 1000.
Unknown Speaker
Chips. Yeah, T 1000 jobs.
Host 2
So then I got that working earlier this week. I finished up wrapping up the timings last night and it looks amazing. I'll post the video or something on the blog. Yeah, it looks great. I was watching it earlier today. Yeah, we actually had it playing like a 1080 p video of an aquarium. And it was very soothing, huh. So I started working on the next step, which was is basically taking Raspberry Pi compute module, which is like their memory stick style, I guess board that plugs into a sodium connector. So it's like $1
Host 3
Reminds me of old processor boards. Yeah, that used to plug in the Pentium
Host 2
twos did that? Yep. into a socket a, I think so. I don't have it. Um, I'm working on the compute module version. Basically, I want to be able to plug the compute module in, break all the pins out, and it has the LVDS chip on it. So all you do is plug your screen in. And if there's enough interest in that, I'll probably try to package it in a way where it also has like a lithium battery controller and all that stuff on it. So you basically, you have the makings of Raspberry Pi laptop. Yeah, yeah. Cool. And I have been looking into how to do like keyboards, you know, it's probably going to be cheaper for people to buy off shelf keyboards, this paired up with is making your own is pretty pricey. Trying to buy all the cherry switches and stuff like that.
Host 3
Oh, yeah. And it's a pain.
Host 2
So yeah, if you're interested, shoot me an email. Yeah, we'll see where it goes with the Kickstarter. Awesome. Steven, science museum project
Host 3
is underway. So in, I think it was episode 58. We talked with Patrick Renner and Kelly O'Brien, about the the project that we've been working on for the Science Museum here in town. And in fact, right after the podcast, right, when we're done recording this, I'm heading over to finish the project, or finished the first half of it, I should say. So we're delivering two things to the Science Museum. One of them is is a not necessarily like interactive, but but a drill bit, basically that drives up and down and turns around and kind of simulates drilling a well, I. And so we're finishing building that tonight. So it's actually so funny enough. I've obviously done all the electronic side of things. So all the controlling and, and all the motor turning and the limit switching and all kinds of stuff like that. Now, I had my whole box all designed up, and I built that all up. And Parker and I had a conversation yesterday, I was leaving macro fab and I was like, I had this box in my hand. I was like, I'm gonna plug this in, and it's just gonna work. I'm like, bullshit. Yeah, this is bullshit because it never happens that way. But damn it if I didn't plug it in, and it just worked. And I'm kind of in awe
Host 2
about the release that day.
Host 3
Yeah, yeah. Well had released but I changed them. And I don't know yet. SSRS Yeah, I had SSRS. And I decided to go with with actual physical contact relays. In fact, I chose relays that have, they're rated for a billion operations.
Host 2
So how long is that lifetime?
Host 3
So I understood I kind of calculated roughly that it will receive 360,000 relay clicks a year. And so, you know, extend that out to a billion this thing should last a long time.
Host 2
Yeah, the the joke I'm saying is like, the world like the sun is expanding into like a red. Red Giant. Yeah, right. Everything's vaporizing away and like the drill. So going,
Host 3
my project is clicking away. Yeah, the the universe has gone into a big crunch. Yeah, everything has gone and my drill is floating out in the middle of nowhere. It's like those
Host 2
animations where they show like, what happens when you get close to a black hole. When you get all stretched out? It's like
Host 3
yeah, yeah. So I got everything. Everything's pretty much working. It's not all the thing is I did a simulation with all the motors outside of the device. So the drill bits not actually physically moving yet. But all the all the drills are turning and alignment switching is working. Yeah, like you, you do the things that it needs to do by clicking switches. And it turns the motors the way it needs to, and it just worked out well. And I used the the PLC, the Arduino PLC from plc.us, which we found on Amazon and and we had used in a previous project at McAfee, I use that in this. And that thing is killer
Host 2
is way overkill for this. But you could have done this with like a couple flip flops. And in some op amps,
Host 3
I could have but there's there's a lot of like, safety things that I wanted to cook into it. And I wanted it to have some kind of smarts such that if something goes wrong, it goes into fault conditions. And so I've added stuff like that. So yes, you could have done this purely with gate logic and like discharging capacitors, if you wanted to. But that would have taken longer. I think we're taking longer. Yeah, yeah. So and if you make a mistake with it, you have to reroll a design. You can't just click reprogram. And I'm not that good. If I if I were to do it that way, as a gate level timing design. It would not have used
Host 2
the limit switches to Yeah, reset stuff.
Host 3
So um, I guess late tonight, I'll see if I can take a picture if it's all put together. Cool. Yeah. So I've also been working on the synth that I've been talking about for a long time. It's about 50% done, because I told, as I've said on the podcast before I'm building it by hand. I mean, the board actually like placing resistor,
Host 2
like actually impacting the silicon well, with Nikken.
Host 3
So yeah, no, well, I mean, I could have put this on our pick and place machine, but I really, I don't know, I'm weird.
Host 2
You can sell it. I could sell higher price good artists, and it's all rated by an artist. It's not.
Host 3
Yeah, you're right. You're right. It's beyond handwired. I mean, it actually is going to be handwired. But it's, it's so it's artisan engineered artists.
Host 2
Oh my gosh, the biggest amount of ever. Yeah, so
Host 3
I the price tag on this is gonna start at 35,000 If anyone likes would like a single voice synth for $35,000. So yeah. Assuming my weekend is open coming up here soon, I plan to actually go to the fab on Saturday and crank out a ton more of the synth. Awesome. Cool. That's what I've been up to.
Host 2
Okay, onto the RFO. Yep. I don't think we have anything else that we've been doing. That's anything that's interesting.
Host 3
Well, we have a lot more, but our listeners probably don't want to hear about it. That's true.
Host 2
I started this resistor today. Okay, RFO we have this week, the cuddle cub. In the same vein, we have the Google patent for a creepy teddy bear. Huh. SpaceX is launching a new a well, not really new. It's a used rocket, which is like the first time ever since launching a used rock. Well, I guess the space shuttle kind of did but besides the point, and actually launching it, like as we're recording, I think is actually just launched. Billy. Yeah, I think launch at like 532 Okay,
Host 3
we'll talk about that when we get to it because I had some questions on
Host 2
and then a cool project by Joe Grande, where he modified a two tunes toothbrush.
Host 3
That was cool. I watched that video. Earlier this week, all right, so
Host 2
cold cup. It's an IoT teddy bear, or what Internet of Teddy's right Internet of Teddy's? That's right. Yeah. Basically, it's like I guess it's a it's a device that connects to your phone. And so that you can monitor what your kid is doing. It can play lullabies, it can wake up your kid in the morning, all the stuff that you should be doing as the parent.
Host 3
Well, it's it's a it's a data mining, teddy bear
Host 2
data mining your kids. So started early before they even get on the internet. Basically,
Host 3
if you go to their website, it kind of described that this is a device that when your kid goes to bed, you give them this nice teddy bear. And then it spies on them as they sleep. Yeah, it's
Host 2
like it's like a really, really fancy baby monitor. Yeah, right. And the thing about it is, well, I'll read what they said. Not only is cuddle cub, great for kids, but great for parents as well be in control and in the loop for every night's bedtime adventure, giving you extra time you deserve. And I read that and me was like, so you can have sexy time and know when your kids getting up.
Host 3
I like I like how they said bedtime adventure. Man, I wish I could have an adventure go into bed. That would be great. So So I mean, it's basically the I mean, it's it's got a couple accelerometers
Host 2
inside. It's a Fitbit inside a teddy bear.
Host 3
That's actually a really good description. That's pretty much it. You know, How funny would it be if they just bought like Fitbit rejects? And just some of them and crappy teddy bears from China?
Host 2
No, they look pretty good. I don't have kids. So I guess it's something about trying something different, which is kind of cool about it. Because if you can figure out like is your kid getting enough sleep? You know, it's actually I think that's actually more important for young kids. But probably teenagers is know when your teenager is actually getting sleep and not sleep.
Host 3
Well, but but I think it's actually meant to be like, held as you sleep. So it can detect movement and things like that. So I don't know, I wasn't holding teddy bears when I was a teenager, you might know.
Host 2
Talking about like, you know, like maybe an IoT pillow or something.
Host 3
Yeah, then it's not a bad idea. Actually, my
Host 2
hell I need one of those tell me to go sleep more.
Host 3
My wife has a Fitbit and it has like a sleep mode or something like that. And it she She tracks her sleep with it. And she sees if she's getting quality sleep or not. Basically how restless she is. Oh, and and that's you know, she's doing I don't know, she's tracking it some doing some kind of something with it. But But ya know, it's so this is this is something it's, I said spying on your kid earlier. It's not spying on your kid. It's making sure everything's cool with them.
Host 2
The next topic, mining your kids. Yeah.
Host 3
The next topic, though, is kind of spying on your kids, though. So So the title is Google patent for creepy teddy bear. That was a title of an article that I read earlier today. And it's, it's a really kind of an odd subject because Google in 2015, I believe applied for a patent for a teddy bear that has a suite of sensors and motors that has the ability
Host 2
to sounds like the makings of like five nights at Freddy's.
Host 3
Do you have no idea? You have no idea? How creepy This is?
Host 2
Well, okay, powered off the blood of your children.
Host 3
So this thing has motors that the patent document has shows points to arrows to motors in its legs. It has optical sensors. It has microphones in its ears. And it has the the patent document talks about the ability that it can sense certain motions, and then the teddy bear will actually physically move such that his eyes look at you. I know, it's like what the hell and if it hears certain things, it can like pick those up and start paying attention to them.
Host 2
So it's like they like integrated with. Okay, Google.
Host 3
Yeah, yeah, but in a really creepy way. Yeah. And so, I will admit, I'm, you know, I'm not trying to make this sound like conspiracy theory theory thing. And I very admittedly don't have enough information on this being as I read a lot of the patent document like 30 minutes ago, so but but the thing is, like, there's a lot of diagrams about it shows like a teddy bear, and then like sensors and then an arrow to like a server somewhere. I'm like, You're kidding me, right? This is really big.
Host 2
There was an issue was a couple years backward last year. We're like an IoT kid device. I think it was like a webcam or something or something similar like it had a webcam in it. That's right. And like, basically hackers got hold of the database and published everything.
Host 3
Yeah, yeah. Well, they, not only were they publishing, like just information, they were publishing like recordings that this
Host 2
morning and pictures taken that this thing took.
Host 3
That's creepy. Yeah, that's really cool. But it's also like, you know, step back for a second. Why is Google Why does Google have a patent for a teddy bear that spies on? You get them in the system earlier? I guess so. Get them used to it.
Host 2
Host 3
Google's gonna own the world?
Host 2
Eventually. Yeah, real soon. So
Host 3
that's kind of interesting. We'll post the we'll post the the patent. Yeah. for that.
Host 2
Five Nights at Teddy. Teddy. Yeah. So SpaceX, yeah, SpaceX.
Host 3
They did things. Well, I don't know. You know, well, they're doing they're doing
Host 2
something right now. I'm gonna check real quick on the computer phone.
Host 3
Oh, the good old fashioned computer phone. So they're launching a used rocket. So the question I had earlier when you said a used rocket, does that mean that they bought a secondhand rocket from someone else? No. And now they're launching it. It's
Host 2
they're one of the rockets that they are the first stage of the Falcon nine that landed? Oh, they basically tore it all down, checked it all out and put it all back together. And they're like, Yeah, let's go. The dry fired it's they dry fired it earlier this week. I think the launch is right now. I'm checking real quick. Pardon the Interruption people.
Host 3
That that would be funny if there was like a Craigslist for used rockets. But you'd have to speak Russian or something like that. Anything fun? Some good. Okay. See?
Host 2
Apparently it all worked. It actually really landed as well. Oh, so it's already landed? Yeah. So it's already landed. And actually it's right now. And from right now 10 and 10 minutes, the second stage will reignite the finish off the burn. So and the first stage is already landed on the of course, I still love you barge.
Host 3
where's the where's the barge at right now?
Host 2
Middle of the ocean. Earth.
Host 3
Somewhere in 70% of the earth. Yeah. So somewhere in that area. You know, SpaceX should buy the old Apollo rocket and just launched that just Oh, the one for shits and giggles. Yeah.
Host 2
Yeah, that's refurb everything on that though. Yeah. But
Host 3
SpaceX do it. That'd be fun.
Host 2
Do you think Elon Musk would come down with just a blank checkbook and be like, just write a number down? Yeah.
Host 3
You know, he probably actually could. Yeah. That's his own personal rocket. He takes that to the high power
Host 2
is going to be our our code word personal rocket.
Host 3
Host 2
Yeah, I think that might be that's our that code word personal rehearsal
Host 3
rocket. That sounds terrible. The first code word we ever have his personal rocket? Yep. Oh, wow. Well done.
Host 2
We're getting close to the end and had to figure out something.
Unknown Speaker
And that's what we learned. First of all rocket
Host 2
landed on a course I still love you barge.
Host 3
Oh, geez. Okay, next topic.
Host 2
Two tunes, which is a hack by Joe Grand. So I didn't know these existed are apparently two tunes are a electric toothbrush. Yep. That vibrates your enamel in your skull, your teeth, mm to produce a frequency that you use pick up. And it plays music. And apparently, Joe grande likes rock and roll and not like Kidz
Host 3
Host 2
Yeah. She's still making music.
Host 3
I I am not up to date on my Hannah Montana Nickelodeon. In fact, I think she's kind of a lot crazier now. Once again, not up to date.
Host 2
So anyways, he hacked it basically replaced the amplifier and all that good stuff in it with his own circuit that plays a WAV file off an SD card and so that you can hear Metallica whatever you want to listen to.
Host 3
Yeah, so it has a transducer that's basically behind the bristles that no jiggle, it was just
Host 2
actually modulating the frequency that fiber did that the whole thing Yeah.
Host 3
The transducers the thing that actually does the vibration. Hmm. And so you send you send a WAV file to the amplifier and the amplifier then jiggles the head of the toothbrush right way in the right way. Yeah, in just the right way. And then and then if you think about it, it's actually really creepy. You're hearing it by the fact that it's jiggling your skull, you know?
Host 2
Like, you know, what, 10 kilohertz or something like that, you know,
Host 3
I've actually I've, I've totally you know, put my mouth and bit a guitar once and played it and you can hear it. You can hear it so well. It's really creepy. So, but very cool. Well, the only way you can truly enjoy the sound of guitar, you have to taste it. Yeah, a real musician gets a flavor for his music. Oh, Joe's got some cool stuff that this this was a fun little project and the fact that he made like a custom PCB that fits inside this like $10 thing. It's pretty cool.
Host 2
So yeah, and that's going to Oh, yeah, we probably should. Again, thank our listeners. Yeah, absolutely. Please tell a friend a loved one, or coworker yet about the podcast. We are giving away koozies if you gave out the code word,
Host 3
yes. Send us an email with the code word that we mentioned and forgot the code word. Yeah. Personal rocket. And we will we will get we'll get a koozie off to you.
Host 2
Yeah, so we'll catch up next time. This was episode 61 of the McWrap engineering podcast, where your host Parker
Host 3
Nolan and Stephen Craig. Later everyone take it easy.
