- Wagon Chime Module Repaired
- StarWars Detonator Prop
- RPI3 CM Motherboard USB Hub Saga
- Page 14/15 of the datasheet
- PRTCTL or Port Control
- Single I/O that operates as a input and output
- It operates as an open drain with an internal pullup
- When the USB Power Switch senses an overcurrent it needs to drives the PRTCTL pin low
- Then the LAN9514 also drives the pin low
- This PRTCTL needs to operate the enable pin on the USB Power Switch
- MP62551 or TPS2054B
- Would need 4 MP62551 but I can provide 2A total verse 500mA
- Operates the way the PRTCTL needs
- Possibly breaking this HUB circuit into its own to prototype?
- Improving the Prop Dev Stick
- Beginning the eq build. There is a lot to do so it is taking a bit of time
- Gold fingers and connectors – They work!
- Trying a special coax connection – Different rings on top and bottom
- Bluetooth chip doesn’t need a battery because it harvests energy from the air
- Embedded in consumer products to provide easy access to a digital manual when the original paper version is long lost, or it could be put on a clothing label and used to communicate the optimal settings to a washing machine
- $30 million financing from Amazon and Samsung
- Possible release in 2019 but they are shooting for 2020
- HOWMAX30 – MAX-30 Single User Earplugs
- Incorrect part listing on Amazon leads to hilarious reviews
- Bluetooth chip doesn’t need a battery because it harvests energy from the air
Visit our Public Slack Channel and join the conversation in between episodes!
Special thanks to whixr over at Tymkrs for the intro and outro!
About The Hosts
Parker Dillmann is MacroFab's Co-Founder, and Lead ECE with backgrounds in Embedded System Design, and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. He also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components. Parker graduated with a BS in Electrical and Computer Engineering from the University of Texas.
Stephen Kraig began his electronics career by building musical oriented circuits in 2003. Stephen is an avid guitar player and, in his down time, manufactures audio electronics including guitar amplifiers, pedals, and pro audio gear. Stephen graduated with a BS in Electrical Engineering from Texas A&M University.
Host 3 00:00
Hello and welcome to the macro fab engineering podcast. We are your host, Stephen Craig and Parker Dolman. And this is episode 155. So it's been a couple of podcasts since we've had just a Steven and I podcast. So this is kind of like a project update. And a refresher. Yeah, refresher, the Jeep wagon chime module that we were talking about, I finally fixed it, I think you've made it. I haven't plugged it into the wagon yet, but going by the factory service manual, it all functions how it should function, and just just do a reminder of what what all that was. So it's a it's a circuit circuit board module that goes inside the Jeep Wagoneer that basically when you leave your keys in the doors open a goes belong, belong, belong belong and lets you know that your keys are in the ignition. And it was toast, right? Oh, yeah, it was. All the capacitors were all exploded. So I replace all the capacitors. And then we kind of got it to work. But it would like die, it would go. Like that kind of noise. And so we and basically, I started flexing the board and then it started working again. And seems like oh power, we need to re solder it. But the problem was it was like coated in like some conformal coating, shell shellac stuff. Yeah. And so if you tried to solder it, that stuff would actually got to the point where because I started just like trying to melt through it, and just re solder everything. But the problem with doing that it was actually contaminating the solder and putting voids in the solder. Right, like making holes and stuff. It was really, I guess it was heating up mixing in and then out gassing and doing really weird stuff. So basically, I put some epoxy remover on it. And that got it off, strip the hell off of it. Yeah, I just shipped it all off. And then I sucked up all the solder on it, and then re soldered it. And it functions mostly I don't know if this is how it's supposed to sound but at least most actually does what it should do. It beeps so I'm gonna get fired up. This is going to be alive test. I have actually not heard this. So this is a first for me too.
Host 2 02:27
Alright, so when you first powered up, it makes like a sound. Okay. I don't know if it's supposed to do that. But this is like the always on. So it's, it would only do this the first time you plug it in basically. Sure.
Host 3 02:43
So that dies. And then you have to replicate like open switches like the door is ajar. And the key isn't to issue. Okay, so this module is a little blue plastic box and it has a bunch of terminals on the end. And did you just apply power? Or did you have to do anything else to get it to do that? Well, I just did that I just applied power. So that's like, I guess that's the whole circuit powering up and then you have to feed it the signals like key in which is I just did that. Okay, and then I am going to fumble around. I didn't bring my alligator clips. See you having to finagle it. So this is this is when your
Host 1 03:20
Doors open and Keizer and oh, that's, that's a beautiful sound. And then this is when your seatbelt is undone. That does this
Host 3 03:37
Weave all heard that before? Yeah, it's such an I'm gonna turn that off. When do you have to short pins to do that? Yeah. So you you you apply power to it. Yeah, to the power pins. And then one pin gets power, because your ignition is in. And then one pin is your door ajar switch. So you pull it ground. And when you pull it ground, that means the door is open. And then the other pin you pull ground is basically your seatbelt is undone. Got it? Got it. Okay. Yeah. And this was the unit that had that weird op amp, right that we kind of looked at a while ago, or did they like to discrete one or am I getting mixed? No, that's the air air conditioner module that had a blown up transistor. Oh, that's right. Yeah, we actually I actually never made a schematic of this. Okay, so you don't you don't know exactly how it's doing anything? Yeah, it's got some, I think we'd looked at some it's got like an gates or not, or not, nor gates. I think it's four gates. Anyways, it's got some discrete logic blocks in here. And then it's probably got a oscillator, one that's making the tone, and then one for the seatbelt. That's telling to actually turn on and off to make the boom. Right, right, right. So do you know if it's an oscillator chip, or how are their actual it's discrete in here? It was all discrete. Okay. Yeah, I think it's discrete plus We should actually perform for the next podcast, which I shouldn't actually draw schematic out for it.
Host 1 05:04
Yeah, that'd be fun. I would love to see how they actually accomplish that. Yeah. But yeah, it functions and I just got pop it into the wagon after I do a schematic and yeah and find out if it functions in its actual home.
Host 3 05:17
Yeah and the actual home because it would it would kind of work in its original home but it would sound like a you know dying rabbit is I think is the last time we talked about it. Mainly that was, you know, garbage capacitors and yes and a broken board. Yeah, some probably had like hairline fractures all over the solder or whatever. Congratulations. I think you're one of the few people who have ever fixed that module before. Probably I'm actually I think I'm the only person ever fixed the AC control module. Because every single time I google that part, everyone's just like, yeah, just go to the junkyard and hopefully you find a wagoneer. That's got one. That's great. And I bet you're, you're correct about the chime module. There's one more module left. I don't know if I'm gonna fix it or not. It's the cruise control module. Okay. And mainly because that wagon is eventually going to get an engine swap. And it's going to have an electrically controlled cruise control instead of the analog. It's actually a box like six inches by six inches. It's ginormous. Okay, to do cruise control, so and I assume it doesn't work, right. That works. Okay, but jerks. Some RC timer in there is the capacitors exploded. And so it just like ramps up immediately. Orange, noisy, and it's like going crazy because of that. Oh, just hitting the rails? Yeah, doing something like that. Yeah, it's good. I think we should at least open it up and take a look at it. Yeah, you never know. Maybe it's just one capacitor just blew its guts and you just replace that and you got smooth control? Yeah, I doubt it, though. Yeah, I bet there's gonna be like this. And I had to resort to the whole board. And it's probably conformally coated? Probably. Where is where is the child module located in the car? It goes under the dash where your like knee would be? Okay. I thought so. Yeah. Yeah, it plugs into like a fuse box looking thing. You know, that's interesting that they made it like its own individual thing that plugs in as opposed to something that's like hardwired? Yeah, I think it's because of just the age of that vehicle. Because the original wagon ears were designed in built in 67. Yeah. And so you have, you know, over time, new technology creeps into it. And so they just keep adding these modules on. I mean, like, seriously, the cruise control module from factory is duct tape to the bottom of the dash. Wait, really? Yeah. And AMC had a part number for the duct tape. Oh, wow. Yeah, they probably have a drawing for it. Also a bitch. They have a drug with like dimensioned duct tape. Yeah. How with like tolerance on the length, plus and minus three inches. No, and I bet you I bet you they contract somebody to like cut duct tape to length, so they get boxes of like pre cut duct tape, duct tape. So like, and that's because I took like the headliner down. And the wires are seriously just duct taped to the ceiling. That's great on us. So it's like, it's seriously one of those things. They didn't change any of the sheet metal tooling or anything over like 50 years. And so that's how you get stuff like this. That's just like a module that was just the shoved in there like that. It works. It's from another car, but whatever. Yeah. Hey, over the weekend, I was I was watching a or listening to a documentary about like gizmos or something like that. And one of the one of the items that they call like a really useful gizmo is duct tape, and they talked about useful things that duct tape has done in the past. And the astronauts that went up in Apollo 13 took a roll of duct tape with them. And when they had the carbon dioxide issue in the head built make the scraper built. They built a filter using socks and duct tape and it worked. So there you go. Always take a roll with you. Or, you know, take a roll of gaff tape. Gaff tape is better. Yeah, gaff tape is better. So why is gaff tape better? It's a I think it's a stronger weave and stickier adhesive. Okay, because I have a couple of rolls around here that I always use. It seems like that he says less gummy as well. Yeah, also, it's a Gosh, what is it duct tape is like a plastic and and what's it called? cotton fiber, whereas I think gaff tape is some other kind of fabric like I don't know something a little bit more robust. And so it doesn't get it doesn't get as gummy. As for nanoparticles and some Whoo. Actually, okay, so slight tangent. I've always wanted to get one of these there. It's super cool that I think it's called the gaff gun. It's okay, you know those? Gosh, those measurement tools, what do they call it? I'm gonna sound stupid here.
Host 3 10:15
It's a measure. Well, no, it's a tape measure, but it's a it's like a wheel that you put on the ground and you roll it, and it'll tell you how far you walked. I don't know what those are called. Oh, I know what you do. Like you can fly. You can get them everywhere. But yeah, it's basically will you walk and then you find out how far it is? Well, okay, so the gaff gun looks like that. It's a little like a trolley that sits on the ground, and it has a long handle on it. You put a roll of gaff tape in it. And then you can feed cables into it, and you just roll it on the ground. And it tapes the cables. Oh, yeah, I've seen those. And you can drive it around. And like, depending on what role of gaff tape you put on it, you can you can put like, you know, five or six cables in a row, and it makes this really nice path. And for anyone who's like ever done like live sound or like worked on a stage or anything, doing that by hand sucks. And it takes a long time. But with this thing, you just kind of like boop, boop, and go drive wherever you want. And there's, you know, cables take to the ground. That's my tangent. Yeah, that was great. I know. I've seen that video of that. Gaff gun. So yeah, it's awesome.
Host 1 11:20
I think it's called The Gift gun. I could be wrong. It should be its name. Alright, so you got some other stuff that you've got done, right?
Host 3 11:28
Yeah. So I've been working on that Star Wars detonator prop. And so I got all my 3d prints, I got them. The first base coat painted. I'll take a picture for the blog because people can't see me holding these in front of a webcam. So I'm using like a rust oleum silver ish paint turned out really good. This is this will be like the base coat. And then I want to do dry brush on it to get into all the cracks. And then I don't know how exactly I'm gonna do yet and probably wear gloves and then get some like, like, goopy, some kind of goopy tacky paint to give it that kind of grungy greasy look. And then then clear coat it with like a matte clear coat. And then that should be the paint. It should look pretty good. I want it to look like it's been sitting in the bottom of like the Millennium Falcon for like 80 years. So so it's a basically the Star Wars equivalent of a grenade, right? Correct. And so I been building a circuit with a Arduino Nano and like a Canon L it's the LM 387. I think is that like the op amp that a lot of people use for like my first amplifier. 386 Yeah, 386 Yeah. Okay, yeah. So I've got one of those low board. And so I'm going to fire it up and then put the speaker because got a little piezo speaker. So the audio quality is not the best because it's a square wave going into a just general purpose op amp into a piezo. So this is nothing new. No audio files. Yes.
Host 1 13:12
Cog ears if you as a war. Now, I've heard that it's not it's not bad.
Host 3 13:17
It's not that. And I've got some LEDs that blink in sequence. So I can post the video on the blog as well. So So you basically wrote this firmware to do this. This audio, right, and basically hard coded this audio, I guess lookup table in a way, right? Yeah, basically uses just the PWM function and just hammers. I'll go ahead and play it and I'll ask a question. That's all I did program a an explosion sound that's very reminiscent of like the Atari 2600 days. Yeah, Josh, please put a limiter on that.
Host 1 14:02
Okay, here it is one more
Host 3 14:03
Time with a limiter on it. The did when you wrote the code for that? Did you just write like a table that's like, play this frequency at for this duration? And then move to the next thing? Yeah, I basically I made a state machine. And so it says do this state for X long do this state for X long. And each one of those is like each each state has its own sub state. So it's like an on off. So like because there's a blinking LED. And so when the LED turns off, it turns off the tone does the pause and it turns back on etc. And then at the end, I basically just wrote a I kind of broke the state machine rule and just had a while loop. It's a while as it ramped up so you get that And then the didn't have another say at the end of the whoop, which was the explosion in quotes. And did you just do random noise for the explosion? It is random noise from random periods of time. Oh, that's great. So wait, wait, the explosion is different every time right? Yes. Wait, no, it's not. It can't be because unless you put the random seed function into the Arduino, right? I don't know how the random function Arduino works. So it's been my experience. And I don't know maybe on the Nano, it's different. But if you do random, it, it is random. But it follows the same path every single time you turn on unless you do the random seed. At the beginning and the random, I can't remember exactly how it works. But you can randomize the seed. But that's awesome. That's one of the best ways actually to do for the seed is actually read a analog pin, that's just an antenna. And you just get noise. Yeah, actually, what's funny is, I just did a project recently that we did that I was using three, what are the three ADCs on an STM chip that were all 12 bit, but I had an extra 16 bit ADC lying around that I wasn't using. And I didn't need that resolution. And it was just free floating. So we use that as our random so we just read noise 16 bits of noise. And, and it does great for random. It's perfect for it. So I'm going to be finishing up the paint and then stuffing that circuit into that, you know, little detonator, 3d printed detonator. And I'm thinking about once I get this working, this will be like the prototype because I kind of want to make a couple more for our d&d group. Or I guess, Star Wars de 20 group. And so I'm thinking about modifying this the 3d model to actually have bosses in it and then just make a PCB. I just drop into it. And then it works. Because you know, more projects, right? Yeah, yeah, yeah, there we go. You need to you need to create an a network of thermal detonators that you in Texas can like flip your thermal detonator, and it would flag me and roll dice for me. Like just now that would be cool. So like, we're talking like an IoT detonator that's got a display on it for a dice. Yeah. But like, I can hold my thermal detonator and see you roll your dice. That's actually a cool idea. That would be really cool. Yeah. And it would have to like Buzz and beep like you did? Yep. Although it'd be going crazy the entire time. So turning them on and off. That's actually one thing I might want to add to this is a is like a vibration motor from a pager. And so when the explosion goes off, it actually moves. Oh, if you put it on a table or something like that, yeah, it goes. That's fantastic. Yeah, no, you need to post some pictures of it. It's cool. Because it has like a little. The way it's activated is it has like a little flip. I don't know whether the little slide switch on the top, which Okay, let's talk about that for a quick second. That seems way too easy to activate a curtain. It doesn't little slide switch, even a modern grenade where you pull the pin, you still have to release the lever for it to stay at the time we use it, pull the pin out and then release the lever and it goes flies off. Right? Because even if you pull the pin, like that's the I think that's the misconception. If you pull the pin on a grenade paper, like, oh, the timer is going no it it only goes when it leaves your hand. Yeah, so not a thermal detonator. It just goes whenever you flip that little thing. So if you have it in your pocket, you know, good luck.
Host 3 18:56
Okay, um, update on the Raspberry Pi three compute module board, you've got a lot of stuff to get. Yeah, this is the USB hub saga. So I'm using the microchips Wan 9514. And I've been routing on that route. And I guess I've been drawn the schematic of that, I mean, kind of had took some time off in this project for like a month. And me getting back to it. And so I'm at the part of that circuit now where I need to do the USB power switching for controlling how much current the USB ports are giving out. And so the idea is when the USB power port pulls more power or overcurrent. Then the the land 9514 Chip needs to be needs to be told that hey, port two has pulled more power. And so it can tell the OS that something bad happened and so he can shut down that USB communication port. And all that happens in like a split second right? And so you don't blow something up and lose data or corruption. Yeah, that's always fun when you're working on customer gear and either, you know, the manufacturer makes a mistake, or the customer made a mistake and you plug it in and Windows goes USB power surge has been detected. That's happened. And that's what this whole, that's what this whole circuit does. The inland 9514 is kind of weird, because it uses one pin to do this whole thing per port. So it has four of these, what they call port control, PRT, CTL, go figure. And there's a single IO pin that controls one port. And it's operates as an input and an output. And so at first, when I'm power up, it operates as an open drain with an internal pull up, so it pulls it up to the one or whatever 3.3 volts, I think is what it is, or five volts, I can't remember, it pulls it up. And your USB power switch needs to be connected. It's enable pin and it's pin for notifying. So like it's a alert pin or fault pin, I think it's right term fault pin need to be connected to this one pin. And so when it pulls up and needs to be held the your your USB power switch needs to be enable high, right. So it's enabled allowing the juice, but your fault needs to be low so that the fault pin can pull that low. And then when the LAN 9514 to text that goes low. The land 9514 asserts its dominance over that pin and yanks it lower to zero turning off the power USB power switch because it pulls it to enable low. It's like this weird act of like we had dance. Yeah. Because like as you use the power switch is pulling the fault pin low. That enables like, when is it going to turn off and then if it turns off, if the Enable pin goes down? The good thing is a lot of times these fault pins are still asserted correctly, so they don't get in this tri state weirdness. Okay, yeah. So yeah, it's kind of weird. How is this described in the datasheet? Is there like age 1415 for the land 9514. I tried to explain as best as possible. Because I tried to condense like basically two pages of stuff in like three sentences for power control. Yeah. Okay. So if you go to that page, there's a diagram of how it's wired up. And once you look at that diagram, it's pretty obvious of how it works. Got it? See, I skipped over it.
Host 1 22:51
Yeah, they got like little thought bubbles and stuff. It's weird. Yeah. Oh, no. Go one more page down. Yeah, well, I
Host 3 22:58
Was looking at Yeah, no, I was looking at the page up. I see what you what you're getting at. But no, the one before was talking about the power connections with thought, Oh, yeah. That's the physical Ethernet physical connections and stuff. I like how they drew every single bypass cap on there, too. Oh, yes, it just pockmarked with with the Bible, this thing that's got a lot of a lot of bypass gaps. And so 404 that USB power switch, I found the MPs MP 62551 which I really liked this part. It will allow me to do basically the maximum over USB 2.0 power which is 500 milliamps. And I can since it's as for USB ports I can use for these. So I get two amps total power, which is pretty sweet. I think last podcasts I talked about this, I was looking at the TPS 2054 B which actually is a four port USB switch, which is really cool. But the problem is, is you only get 500 milliamps maximum out of the whole chip. Got it. And so if you're drawing from all them, you have to split that up evenly. It distributes it. Yeah. So I'm thinking about doing the single chip per channel isolation kind of thing and just run it that way. That's it costs a little bit more but and whatever I'm not It's not like I'm building millions of these things. Sure. Sure. I mean, do you need that with a question is is there a situation where you would need all two amps?
Host 1 24:39
Yes. Of course, right. Yeah. All right. You answered my question then I guess Yeah.
Host 3 24:51
And and both these chips operate the way the port control new land 95141 it. It took a while to find some that actually would work that way. And I'm thinking about taking this USB hub circuit, and making its own sub circuit. And building a board with just this on it. Because this is like, the one part of the Raspberry Pi three compute module board thing that I'm not fully sure about, because I've never tried to design something like this. Got it. And so I'm thinking about making its own sub thing. So it's like, you know, $30 to prototype instead of $100. To prototype. Sure. Yeah. Yeah. Breakout and plus, then I'll be like, oh, yeah, now I have a hub circuit for USB. But think about it. If you prototyped it, and it worked. Then you could just have a two amp USB charging for quad charging port. It's not a charging port. It's just because USB. Okay, USB charging is a different setup. Okay, and what I'm doing here, this is just normal 2.0 Almost stuff, but I want the full current. So, man, I picked up a wireless phone charger the other day. And you know, there's probably old hat for people, but it's the first time I've used it. I'm like, Man, why haven't I been using this? It's freaking awesome. Oh, yeah. Yeah, it's super easy. And I got a new phone the other day. So like, it wasn't one of those things where you have to activate it or like, install anything or do anything. It's just like literally plugging into the wall and set your phone on it and juice. Juices came flowing through it. Yeah, just flow. Yeah. And it charged in like two seconds. It actually has a fan installed in the base because it can get hot doing the fast charging. Oh, cool. Well, it's funny because they on the box, they sell it. And this is a Samsung, like legit Samsung charger. It's not like a third party thing. They said they said it has a fan to cool your phone. When it's fast charging. I'm like bowl. That's that's a fan to. To cool. Your thing. Well, it's charged the phone some marketing stuff going on there. Oh yeah. You got to spin it to be positive. Yeah. And then the last project I have an update on is my old propeller development stick. The PDS these are like my favorite like little tiny boards. It's like my own spin on a little development board for the parallax propeller. Yeah. And for a long time, if you loaded if you joined macro, Feb. You could look at that project on macro fed. That was like the first thing macro fab did right. Yeah, actually, it's still the demo project. Oh, it's still up there. Okay. So like a lot of people have seen the prep dev stick. Yeah. So if you go to the Mac prep website and click demo, that board there is the rev four B or four D, I can't remember of the prop depths, I think it's D, that which is latest version. Anyways, a more started working on the rev five, mainly because I kind of want to make it a little bit smaller. I want to squeeze down because right now it's like 900 mil pin spacing between the two and I want to get done like 800. And so I'm switching to the QFN version of the prop over the qf P, which actually like shrinks down the package size by like 30 40% That's actually quite a bit, I guess you're going from like point five millimeters to point four millimeters pin spacing, and that does a lot well and you don't have been sticking out that yet to it pads are thinner too. So everything just gets smaller. I'm switching to oh four two parts instead of Oh 603. Man, because now I'm not hand soldering these. So I can just do oh four, two. Yep. And I'm going to USB type C for USB 2.0. So I'm going to keep the whole it's just going to be a 500 milliamp USB 2.0 device, I'm just going over the Type C because I can now and the big change is I'm going to change how I want to change how the power is handled. Because I originally have the T eyes TPS to 113 which is a power mux auto switching power mux and so when you have USB power on that's like the normal default thing but if you have an external power source and USB plugged in, it will pick whichever one is higher and use that so if you have like six volt DC coming into it, I actually can't do six volt if you have 5.5 volt DC coming into it or five volts I guess it will default to to the external power instead using USB power. So it's really nice so you don't get like back feeding into the USB port. Does it? Does it always favor an external supply as opposed to USBs? Okay, yeah,
Host 3 29:48
Always favorites like some now that's not very good idea if you're doing like battery charging. You want to use the USB has the power to charge the battery. But this is not not designed for that. Um, the problem with that TPS 2113 is it's 5.5 volts max. And I'd like to be able to use like external battery packs like a 7.4 volt lithium. And so I've been looking at the NCP 3901, which is a dual input mux that's an auto switcher. It's in this weird wafer package, and I've never used wait for packages before. So this is gonna be new for me. It's like a kind of like a BGA package, I guess. But it handles like three or five amps something crazy. I'm like, that's way more than I need, but it's really tiny. And it does wi need it goes up to like 30 volts. The only problem is it doesn't have built in current limiting. So I'm gonna have to add a current limiting switch. I'm gonna have to, I don't think I'm gonna go search through NPS is website. And because I've been looking at this, I really liked their stuff. There's some really cool power parts. And so I'm going to try using some more of their parts just to get a feel for that stuff. MPs feels a lot like Maxim. Yeah, we've talked, we've talked a lot about Maxim's data sheets, and their offerings and how it's kind of awesome that they, they like, they give you a lot of things that you didn't think about, you know, they showed us showcase a lot of really cool stuff. NPS is kind of like that. And it runs a lot like LT as well. So that when the good thing with NPS every single part, I pulled up their website and plugged in the Mauser Mouser had. Yeah. And they had like 1000s of so I'm like, Okay, this is not like maximum and Lt. Devices has good stuff, too. Yes, they show good. You know, the one, that's a really big issue that comes to mind that doesn't really hold your hand is Texas Instruments. They're great. Don't get me wrong. I love Texas Instruments. But their data sheets are kind of they don't they tell you how it works. And that's it. They just are they rely on you to go find app notes in their huge repository. 40 years of AP notes actually probably longer than that. Yeah, for sure. Wait, it's 2019. And they probably started in the 60s. So yeah, 6070 years now. They've got a lot of AP notes, that's for sure. Yeah. The best is when you find that crusty PDF that looks like it's been scanned and Xerox at times. Oh, yeah. I you know, I hate all gosh, I hate it when you find a schematic that's been scanned 5000 times, and you try to look at a value and it it a value of like a capacitor and it's like, well, that could be I guess, 4700, Pico farads, or whatever else. It's just a big blob of black. It's like, whoever did the original schematic, wrote it in pencil, erased it and wrote it again. So this is little bit of smudge. Xerox. Through its life has merged those two layers together. They have become one, they've become one. Speaking of old hand drawn schematics. I've been working with Ben a bit on a Atari 2600 as single chip, Atari 2600. And by Ben, you mean Ben? Heck, yeah. But Benjamin heckendorn. He was on the podcast couple weeks ago. Yep.
Host 2 33:23
So the original Atari 2600s. They have three chips, they have 6507. CPU, they have the riot chip, which is the input output and RAM controller. And then they have the TIA ti A, and that is the graphics and sound processor. Well, at the very end of the life of the Atari 2600. So the original Atari 2600 came out in 77. Around 8786 87. The they were they were still making this thing, which is amazing. But they started like cost reduced the hell out of it, like at each iteration of 2600 was like to reduce the cost.
Host 3 34:07
If you think about 87. The Nintendo Entertainment System had already been out for over two years. Yes, yeah. And so the 2600 is still strong, like in international markets like Brazil. And so they came out with a all in one chip. That was the 6507, the riot and the TIA in one package. And they call it the Jan. And they're very hard to find and actually found one like a decade ago, and it's just been sitting in a box. And funnily enough, like I was reading it like going through all my old junk. And Ben was going through all his old junk and he found his like a day before I found mine. And but he only has had the chip. And this is a dip 64 package. It's a monster chip. It's a Monster Monster chip. And basically I reverse We have a schematic that someone I guess got from Atari from back in the day, but it's incorrect. Like it shows like a 48 pin part for the chance. And it's like no, it's clearly a 64 pin. So we basically repin it out and made our own schematic. How'd you how'd you repin it? Basically going out to schematic because most of the external circuitry was the same. So basically working backwards into the chip. Oh, okay. So you you have a board that accepts the the Jan chip. Yeah, I have the full board. Oh, okay. Okay. Okay. I let you just had the chip. And you were saying you, you reverse engineer. I was like, Oh, wow, how'd you do that? No, no. And so basically, we found out is one of the weird things is, is one of the address lines is reversed on it. So it's like, it's like 123456 710-911-1213 14.
Host 1 35:57
Sorry, flips two of them. Yeah, that was an oops, from the from the factory, right.
Host 3 36:04
I don't know why it's reversed like that. But yeah, it is. That's funny. So. So Steven, what are you been up to? Well, I've been up to a lot, but not as much as you clearly or use huge if you've been saving things up for what I've been saving. Okay, so, you know, I've been I've been working on this graphic equalizer that I've been talking about for a couple of weeks. And do we have a codename for that yet? Codename EQ. Okay. Yeah, that's boring. Sorry, that was really bad. But so I've been I've been working on that. And really, I've been doing the boring stuff that's not really that special about it. So I don't have a ton to talk about. And what I mean by boring stuff is I'm just building it. And so what are the Steven? Yeah, what's that? We're doing a contest right now. In slack, if someone could come up with a cool name for Stephens 20, band EQ, they can get a macro fab shirt. Oh, I like that. Yeah, let's do it. Give. And so, Parker, and I guess we'll both kind of discuss it and pick a codename for it, whichever one we think is cool. So Mac fab rounds. COMM slash flax is that what is Mac fab that slash.com/slack Is that whatever, it'll be in the News notes, go to the good of the podcast. And you can figure out how to get on Slack, and then come up with a name for my graphic equalizer. And we'll, we'll go with that. So I've been building it. And it's kind of going slow, because I've got a lot of other things in the way that so I'm just building it when I have time. And one of the things is one of the boards. So I discussed this last time I talked about it, I ended up using PCI II, pluggable boards or connectors, to be able to accept all of the band circuitry, which, by the way, they look really cool, I'm super happy with it. And all of them actually function pretty well, like the connections and everything. But I've got 21 of these connectors, and each one has 64 pins. So you know, do the math on that. And when you start talking about how much you have to solder. And so I'm sort of juggling right now. It's like, do I want to sit down and program the selective solder machine that I have available to me to do all of that? Which, frankly, it's not the fastest thing to program, or do I want to just sit down and, and solder 1300 solder points with a chisel tip, which really doesn't take that long, you know, so I got an idea. Yeah. Was it turn on the selective solder and just had the fountain sitting there? Spray the bottom of the board with flux and use it as a wave of your hand? Okay. Okay. So you don't do that when you're, you're when the shop foreman is there, though? Yeah. What's a shop foreman? No, no, I was literally this morning, I walked into work. And I was talking to the guy who runs the selective soldering machine. And he said the exact same, it would work. Yeah, no, it would totally work. I mean, it's sort of dangerous. And it's also kind of like skill based, I guess. Or you can just put the board in and just jog the machine. This machine isn't that kind. Let's put it that way. I mean, it's a it's a, it's a great machine, but it's not going to be as like, nice about doing that. So they're actually the machine that we have is a it's an Ursa I don't remember the model number. But what's nice about it is it takes your board in and it moves it to the back of the machine and it has, I call it the pizza oven, but it has a whole bunch of heaters that board it pre heats the board but only from the underside and then it moves it forward and then the you know, the chocolate fountain of solder comes over Yeah, hits all the points. It's actually really super nice. Because the one the one we had a macro fed back and they didn't do preheating. So yes, it was a little funky because of that, but but the pizza heater Really, it helps a lot, especially if you have multi layer boards with ground planes, which my distribution board does have. So, you know, there's, there's a lot of ways I could do this. But honestly, like we've discussed this a handful of times on the podcast, soldering to me is like really therapeutic. I love just like listening to music and soldering. So doing 1300 solder points doesn't sound terrible, it actually sounds kind of fun. So I'm still judging them.
Host 3 40:27
So yeah, like, there's all that and I, I've programmed our pick and place at work, too, with the program for all of my band boards. So everything's there, I just, I haven't gotten a spare moment to load all of the tape onto the feeders and stick it on. And, you know, the thing about it is like, that takes a lot of time. And really the, you know, most of the stuff I build, I need one or two of this, this is a project that's actually you know, worthwhile to do on the pick and place. It's just, there's, there's a lot of there's, there's honestly, hours of work before you even press play. And you know, for that machine to actually go and do things. And it comes down to even like, you have to move the head over the tape and look at the part in the tape and say like, oh, is this the right direction? And you know, there's just so many little things. So I've got all that program, but I'm literally at the point now where I just have to put parts on feeders and throw them in the machine and press go. So I that will happen. Hopefully soon. I don't know, we'll figure it out. I'll be working on that. Didn't close. Yeah. So uh, you know, one of the things I wanted to mention is that I actually did use gold fingers on a lot of these boards. So for those who don't know, gold fingers are kind of like, think of Nintendo cartridges. You know, like the when you when you look in the bottom of a dental cartridge, you see PCB with a bunch of gold contacts on it, and saliva and spit all over? Well, yeah, a lot of humidity from breath all over. Which, which it's funny. I've heard many, many times that like, don't do that. That's absolutely terrible. And in a way, like, yeah, you can you can, what I mean by don't do that. It's like, Don't breathe in the bottom of your Nintendo carts. But like when we were kids, like, that's what we had available. We had our breath, and we had Nintendo carts, you know? Yeah. And the funny thing about that is somehow, everyone came to that conclusion. Yeah, before we had an internet, we figured that out. For the internet, for some reason that worked. And like, No one told me to do that. And like, and that's a common thing. And every kid, every kid knew how to do that. Yeah, it's like that little s that you drew in middle school. The graffiti Yes. Yeah. The graffiti s like, where did that come from? No one knows.
Host 3 42:50
I don't know. A Banksy did it? Sure. But okay, so yeah, I did, I did gold fingers on this. So I've done gold fingers in the past on some some products I've designed and, or been a part of designing. And there's sort of like, what's kind of cool nowadays is there's like a less professional, I guess you could say way of doing gold fingers. Because it used to be when you wanted gold fingers, you you had to provide your Gerber's. And then you would create a fabrication drawing. And you would like have to show bubbles and like, identify areas that you want to gold fingers. And then like show like cross section edges be like, hey, I want you to chamfer put a 45 chamfer on the edge of my PCB. But what's kind of cool now is with like all of these online PCB vendors, you just click a button that says gold fingers. And it shows up gold fingers, which is kind of nice. And by gold fingers, I mean, that a lot of times they also call it hard gold, where they basically they overcoat the or overplayed the fingers such that they're more robust, and they won't break from multiple insurance, insertions into connectors. So, but it's funny, like I went that route of doing hard gold, when in reality, I'm going to plug these things in once, and that's it, like their life is going to be plugged in. And that's it, but I don't know, it was fun. So it's kind of cool. Like, well, you know, it would be fun one day to kind of, you actually create a fab drawing, and discuss, like, why we did it that way and like, but it's also kind of nice to just make a design, follow the data sheet for the connector, because most of those data sheets for the connectors that require gold fingers, they do it this way, and you're good. And then you just press the buttons when you buy the the PCBs, which you know, actually what's kind of fun on the board that I created. The way I did it was I started by drawing the board outline which the board outline frankly was decided by the connector, because it had to be a certain like everything had to be specific, a certain profile. Right, right. The connector datasheet said, just draw it this way. And the only the only thing that I as the designer got to choose is how long the board stuck out of the connector, right. So I, you know, I chose that, but I actually made the top and bottom gold fingers, a single component in dip trace. So I made it a single component. And then I just placed it on my origin and everything lines up, as opposed to like individually creating every pad as its own individual thing, I just made it a single component. So like I have a component that's called card edge. And I just dropped that in, and there we go. So it actually came out pretty easy. So there's actually one other connection that I did, I'm doing a lot of like, things that I don't normally do like I very rarely do cold fingers unless the design requires it. And most of my personal stuff never does. But but one of the thing that I wanted to try for a very long time, but I haven't had a need for it until now is a special kind of coax connection that came to mind a while ago, I wanted to make a coax connection that doesn't actually require a connector, but I could still utilize a connection to my PCB. So I made a really interesting footprint that it'll be a little bit difficult to describe, but I'll give it a give it a shot here. Basically, I made a pad or a through hole pad that the center conductor of my coax will go through. But the interesting thing about this pad is that on the bottom side, the annular ring, or the the actual ring of copper is large, and the top side of the board, it's really small. And the surrounding on the top side, I put a secondary pad that is basically a doughnut. So if you think of the inside of the doughnut, there's a void of copper. And then inside of that is my through hole. So basically what I have is I have my center conductor going through the board. But I also have a place for the braid the copper braid in the coax to solder to. So effectively, I'm trying to make a PCB connection that doesn't actually require any conductor or any actual connector itself, the PCB itself has a connector. And I wanted that because I wanted my ground of my
Host 3 47:23
Coax to go all the way to the PCB, and then my center conductor goes into the PCB. And my actual signal that I'm taking off of the coax, is goes on an inner layer in the board. So I'm shielded all the way to the actual PCB itself. It's probably absolutely ridiculous. And it only makes sense if you're doing this soldering by hand. So it's not like anything you would ever use in a production environment. You can't use a machine to do it. Right, right. But I'm making one of these and I've always wanted to do just try this. So it actually looks kind of good. The the place I got, I got the board's made a JLC PCB, and the drill hits are not exactly centered, but they overall like it all looks good. And there's copper everywhere. So I'll, I'll have to take a picture of that and show that off. And then when I when I actually soldered my coax to it, we'll see how well it goes. Because it's sort of dependent on how, like perfect I cut the the coax coax. Yeah, but I do have a coax cutter that in the past makes, I found makes really, really sharp cuts. So we'll see how it goes. You get a render of it as well. Yeah, well, so here's the I mean, for people who have been listening to the past couple months, I'm designing a new guitar amplifier. And sort of one of the things that I've set myself out for is to 3d model every part that goes into the amp. And I've been slowly doing piece by piece by piece. And I've got the whole graphic equalizer. modelled up. In fact, I
Host 1 48:57
Have, I have one of the input boards that goes into the board that handles all the power and the input output signals. And I have that modeled with all of its components on it, and it looks awesome. But eventually, I will model the coax that goes up to that too, because of the kind of the end goal of this is I want to have a full 3d model of the amplifier, every single part in Fusion 360. And then I want to set out all the parts and I want to build it based off of my 3d model. And effectively the bill of materials that shows up as every part in Fusion 360. So it's sort of an excuse to get better at CAD, but it's also an excuse to just build another
Host 3 49:36
App. There you go. That's why we're always looking for excuses, excuses to do more projects, right? Yes. So that's the goal is for that to be done in. This is 2019. Right? Yeah. So 2019 It'll happen eventually. All right onto the RFO We're burned through these pretty quick. Yeah. This is something that Mike from the Slack channel found. Yeah, no, this is Hi, Ron. This Hi, Ron found and it's the Bluetooth chip doesn't need a battery because it harvest energy from the air. That's a very click Beatty article. Oh extremely. Yeah. So it's not technically harvesting from the air. Is it Steven?
Host 1 50:26
No, it is not. And we have Perkin I kind of like did a little bit of pre research on this just we pregame to write beforehand. Because anytime you see any of these kind of click Beatty things, especially, especially when you see anything that's electronic, where it starts off with like, you can get anything for free. Like my, my bullshit radar like just
Host 3 50:52
Like immediately. So effectively, let's go ahead and I don't know let's let's deconstruct this and look at it. So this company called Willie it, I think that's how you pronounce it w i l IoT Willie Ott has produced. Let's see here, what do they call it, they call it a chip, a paper thin Bluetooth chip that is able to operate entirely without a battery. So they call it the first battery free Bluetooth sensor tag, right. And so
Host 1 51:23
Like, they have this press release that they just came out with, where they are basically saying that they have this small ID tag that's like a stamp that basically sniffs Bluetooth and radio and cellular waves and powers itself based off of the energy that comes from these electromagnetic radiation effectively, right. So it's, it's a ARM processor on a chip that has a fairly unique antenna shape on it. And apparently, what they are claiming is that they can harvest energy from the air power, this processor, read sensors, and then rebroadcast over Bluetooth up to nine meters information.
Host 3 52:13
So it's a little. And by little, I mean a lot click Beatty, and kind of interesting because I would love for this kind of thing to be real. But anytime I see this, I'm just like, Okay, we got to look deeper into this. So I've kind of been reading through their information and going to their website and trying to find some details about how this all kind of comes together. And they have this one minute video that they posted recently, that shows their device, doing a handful of tasks, and things like it in the video, they showed weight sensing and a couple of other things and they show it broadcasting. And what I mean by show they have like these kinds of animations of like, they hold up the tag and like, lines come out of it. And it runs through an old cartoon where like stink fumes come off like characters and it's just like little wiggly squiggly lines. Yeah, it looks like that. And I don't want to make Okay, so I don't want to make it sound like we're shitting on this or any No, no, no, no. But like, because I would love for this to be real. But the first thing that comes to mind is like Okay, great. Like, this is not a new idea. Let's just let's just lay this out like these guys have not discovered something that is like unique. This has been thought of a bazillion times 2.4 gigahertz. energy harvesting is a well studied field. Right, exactly. So what kind of secret sauce or magic do these guys have? And what's interesting is if you go to their website, which is wi l iot.com. I think if you go to their website, it's it's well designed, it's got a whole bunch of stuff on I almost like went crazy, because I went to the website and I thought it said Mr. Bacon, it's Mr. Beacon. Oh, I feel it was just a website about IoT bacon, I'd be I'd be like, Okay, well, we should. This is awesome. Where can I give it money? Yeah. How do I buy this? So like, there's a lot of hype on this website about like, what they are claiming it will do. But there is zero proof across the entire website of it actually doing anything. There's no data, there's no actual videos of it doing anything. But there's like use cases and plenty of information about them getting funding, which they did get funding they got $30,000,000.02 of their investors are Samsung and Amazon, which Hey, super cool. Maybe Maybe they showed them something that have it actually working. And I would love for this to work. Because I mean, there's a lot of applications that go into this. In fact, they show one one of the ones in the video that's pretty cool. I mentioned weight sensing earlier. They kind of showed it was something very similar to the what was that one service that we talked about a while ago that IoT, like, service that we use for the, the beer brewing stuff? Gosh, what
Host 1 55:12
Was that called? UI dots. It was like UI dots. They showed they showed this this thing where, you know, they were graphing or plotting data as it came in, and they, they put a weight on one of their little devices, and their device could sense pressure and things like that. And it was doing so without any external power source, like, you know, how powerful that is, and how absolutely amazing that would be. So, apparently, you know, according to their website, and their press release, they do plan to showcase its capabilities in mid January. So
Host 3 55:47
About now, sometime soon, they will, you know, demonstrate to the world. And if so, like, I would love to know how it actually works, because the power output from a Bluetooth device is so small school, it's so so small. And so the question is, if it's gathering from Bluetooth devices, how does it have enough power to then like, turn up a processor, like, make some decisions about things, and then broadcast on the same Bluetooth like, the stink filter is just like, like, oh, probably, it's probably cycling. So it's got, it's probably goes into deep sleep. So it's pulling nano amps, right? Like roster, and then it sits there harvesting, charging up, charging up charging up, gets to a certain point, and they, you know, fires the CPU at max everything. And then yeah, and then sends out a burst. Yeah, goes back to sleep. So the interesting thing, though, is that with Bluetooth, I think I might be wrong on Bluetooth. So I haven't done a lot with it. But I think you need to have a continuous connection. I think you have to have keep handshaking to keep that connection alive, or is it just streaming? So they're doing something here? But why getting being able to go to sleep like that? Yeah. And to basically turn the radio off. But then when it turns back on, it doesn't have to renegotiate. Because that takes too much power? Probably. Yeah. And that can take seconds to to actually do. Yeah, like and have your processor, like continually broadcasting during that time, would just eat through? Well, and on top of that, you know, you're talking about it was harvesting energy, while it's in deep sleep. If you look at their images, their images shows a little black box like you like a chip that's on a little, you know, a piece of paper that has some copper shapes on it. What's storing the charge? Like where Where's all that energy? Is it good to have a chip could have a solid state super cabinet. Yeah, yeah. Or a connection to a power supply somewhere? They actually, they actually solved quantum entanglement for power transmission. Oh, that's what you actually seen there. Yeah. They're flipping quantum charge from like, I don't know, it's something like the sun and just delivering it to something like this, right. And they're saying it's 2.4 gigahertz harvesting, right, right. No, no, I've seen real time clock chips that have super caps built into them. So that's the probably combining that with a super low power arm. And I have to look at the Bluetooth spec because there's a new one 5.0. And maybe 5.0 allows kind of like a, like initial handshake. And then you could just stream data no matter what, and the device doesn't care. I'm assuming that's what's happened. That would be cool. Yeah, well, and here's the thing, I'm going to read a little excerpt from the front page of their website. It says, imagine a bluetooth chip with a limited lifetime, a small sticker with processing power and sensors for a fraction of the price of traditional beacon devices. And it says the next sentence is we did and are building it now. Now that that statement is I mean, that's a statement saying like, this is already happening. So great. I'd love to see it. This would be super cool. Yeah, I want to see a datasheet. Yeah, well, yeah. It's not on the website. Will it send us a data sheet and we will talk about on the podcast? Yeah, we'll have you on the podcast. And we will start Yeah, y'all can come on the podcast start developing all kinds of cool stuff. Yeah. With it. Yeah. That would be awesome. Thanks. Hi, Ron, for for flagging that in the Slack channel. That's a great topic.
Host 3 59:54
That's cool. Yeah. All right. One last topic. We've been running a little long but I think this is gonna be good. This was from Mike from from the Slack channel. And unfortunately the link has already changed. But on Amazon there was a link for how Max 30 Max 30 single use earplugs. And when you clicked it, it was actually to buy a Honeywell encoder for I guess for industrial devices Yeah, yeah, like like a rheostat kind of thing like, yeah, and it's like 50 bucks. Okay, yeah, they've since fixed it all and so it's just you know, the it's just the encoder and actually says what it is but the reviews were are amazing gold. Yeah. is So this is supposed to be for earplugs so it says worse earplugs ever stuck them in my ears connected to a power source. That's when things went south. Pros. I definitely can't hear anything now. Cons. The hearing loss is permanent. I think there's another there's another comment about like, somebody had to have their wife like screw them into their ears or something.
Host 1 1:01:07
Oh, that's great. That's great. See, join join the Slack channel and you can get all kinds of fun stuff.
Host 3 1:01:13
Yeah, that was good. Well, I ought to find a screenshot of what it was beforehand. Yeah, cuz they just changed it just a few hours ago. Yeah. Cool. So that was the macro fed engineering podcast we are your hosts Parker Dolman and Steven Gregg. Later everyone take it easy Thank you. Yes, you are a listener for downloading our show if you have a cool idea project topic or weird amazon link or weird 2.4 gigahertz free energy device. Let's do it. And I know Tweet us at macro lab at Longhorn engineer with no O's or at analog E and G or email us at podcasts at macro fab.com. Also check out our Slack channel and let Stephen know what he should name is EQ device. If you're not subscribed to the podcast yet, click that subscribe button. That way you get the latest episode right when it releases and please review us wherever you listen as it helps the show stay visible and helps new listeners find us
Transcribed by https://otter.ai