Stephen continues his work on the SSPS and Parker gets busy building an X-Y gantry.
Parker is an Electrical Engineer with backgrounds in Embedded System Design and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. The following year he designed and produced an Atari 2600 video mod to allow the Atari to display a crisp, RF fuzz free picture on newer TVs. Over a thousand Atari video mods where produced by Parker from 2006 to 2011 and the mod is still made by other enthusiasts in the Atari community.
In 2006, Parker enrolled at The University of Texas at Austin as a Petroleum Engineer. After realizing electronics was his passion he switched majors in 2007 to Electrical and Computer Engineering. Following his previous background in making the Atari 2600 video mod, Parker decided to take more board layout classes and circuit design classes. Other areas of study include robotics, microcontroller theory and design, FPGA development with VHDL and Verilog, and image and signal processing with DSPs. In 2010, Parker won a Ti sponsored Launchpad programming and design contest that was held by the IEEE CS chapter at the University. Parker graduated with a BS in Electrical and Computer Engineering in the Spring of 2012.
In the Summer of 2012, Parker was hired on as an Electrical Engineer at Dynamic Perception to design and prototype new electronic products. Here, Parker learned about full product development cycles and honed his board layout skills. Seeing the difficulties in managing operations and FCC/CE compliance testing, Parker thought there had to be a better way for small electronic companies to get their product out in customer's hands.
Parker also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components.
Podcast Transcript
Unknown Speaker
Hello, and welcome to the macro fab engineering podcast. I'm your host, Parker Dohmen.
Host 3
Unknown Speaker
And so what are you been doing this week? Greg?
Host 3
and I are starting. Yeah. We're just blasting into it. Oh, yeah. Well, this week actually working a little bit more on on the supersuit is super stupid power supply, actually making some voltage controlled amplifier for that been trying to put together an analog version of a voltage controlled amplifier. And finding that it's a lot more difficult to do analog than digital.
Unknown Speaker
Yeah, I was seeing the multi sim stuff you are you're actually working on today?
Host 3
Yeah, yeah. Yeah. So making making an accurate, voltage controlled amplifier with op amps and transistors is, is a beast, it's pretty difficult. And I think the conclusion I came to is, you know, 510 hours of work doing analog design could have been replaced with probably 30 minutes of digital circuit.
Unknown Speaker
Yeah. And about an hour of code. Yeah.
Host 3
I think I might go that way. The analog stuff is fun. I love doing it. But I just, I think for this project, it's not going to be right. Yeah.
Unknown Speaker
Yeah, cuz I've seen no, the you haven't you haven't a twin twin transistor, op amp setup, right?
Host 3
Well, the thing is, when for an amplifier, if you're talking about the way human beings hear, we hear volume changes on a logarithmic scale. But the goal was to have a linear change in voltage control a logarithmic volume change. So the the, the actual voltage controlled amplifier chip that I was using has a linear input, or linear current to voltage curve. So I wanted to put a lot of logarithmic current into into it. Yeah. So I could basically control the volume using a linear input voltage. But then the volume would perceivably change linearly, yet, it would actually change logarithmically. Yeah. And doing that with analog is, it's actually not that difficult. But getting everything to play nicely and be stable over temperature is a absolute beast. Yeah.
Unknown Speaker
Interesting. So we're just going to do micro troller Cadac. And I'm just going to run one little DSP algorithm.
Host 3
I think that's yeah, I think that's pretty much how we're gonna have to do it in this case, and you know, temperature won't change anything. And you'll have much more control.
Unknown Speaker
Yeah. math dot C library.
Host 3
Yeah, yeah, exactly. Okay,
Unknown Speaker
and so I've been working on the, we're building this xy platform at macro fab to basically basically build our own machines, kind of like inspection machines, and soldering machines, and that kind of stuff. And so I've been doing all the backend research for that. And I've gotten the, we'll call it the macro PLC, but it's actually just a industrial controller, it does not use ladder logic at all. So you can't really call it a PLC.
Host 3
So what actually is the XY platform. So it's basically just
Unknown Speaker
a giant or not giant, but a small CNC machine that you can use for any kind of machine application. And the the reason why we're developing it in ourselves so that we have direct control over the the actual controller software, instead of using something off shelf. And I wasn't too keen on using some of the open source stuff like for like 3d printing, they use a ramps board and that software, man, because that's all single threaded stuff. And I wanted to use the multi core capabilities of the parallax propeller to drive multiple steppers at the same time without having to lose any basically timing. So basically,
Host 3
it's just a core of a CNC, some some linear drives, stepper motors, things of that sort, that you can just attach any kind of tooling you need to it and repurpose the software for whatever task he needed to perform
Unknown Speaker
exactly the whole point is the rapid rapid turnarounds on on designing a new machine, so 90% of each machine is the same and uses interchangeable parts. And the code is most of the code is actually on the PC side driving the the controller. So today, I got the steppers moving finally, like two weeks late button they're moving now But yeah, it's pretty cool.
Host 3
You want to talk about the, the rails that you used? Yeah. So
Unknown Speaker
we're using a testing, did some rails comm from open maker open build? Or is it open build open build?
Host 3
Yeah, it's open build. And they
Unknown Speaker
use basically it's like an ad 20 extrusion, but instead of rounded corners and that kind of stuff, they actually have V cuts on them. And so a V wheel basically rides in the grooves, and it makes for a really stiff chassis and a really stiff carriage.
Host 3
Yeah, yeah. Yeah. The you purchase one rail, and what was the length of it? 1500 millimeters. Okay. Yeah. 500 millimeters? Yeah, yeah. And with the stepper and all the associated hardware,
Unknown Speaker
I think it was a total of $90. Yeah, it was like $96 with shipping. And that got me the nema 23 motor, 500 millimetres rail, the carriage, all the wheels, the belts and a limit switch. So it was a pretty good all inclusive package. And it worked great. I mean, it took like, about 48 minutes to put together and then
Host 3
yeah, yeah. $90 for that. Yeah. This this new CNC builder hacker maker thing is that I'm seeing come about is really cool that we're able to get computer controlled motion for pro cheap nowadays.
Unknown Speaker
Yeah. Especially I think it's also the all these maker companies like open maker and I think Miko racks and a couple other ones like that are coming out with their own extrusion profiles, and really driving down the price from basically 8020 kind of stuff. Yeah. And it being on smaller scale to help because 8020 I think the smallest they make is 1010 by 10. Yeah, 10. And it's that's a pretty big. So
Host 3
well these guys offer, I think two sizes or rails, they have the rail you bought and then one that's twice as big.
Unknown Speaker
And profile that you have several different profiles, they make a, the one I got was the one by two. And they make a I think they make a two by three is the biggest they make. But yeah, and they make it so that the inner the channels are hollow. And so you can actually run the other side of your belt through it. And so you only have one side of your belt exposed as nice. Yeah, that's really nice. Let some
Host 3
thought into that. Yeah, well, that was originally a Kickstarter thing, right? Or, well, some kind of crowdfunding. Yeah,
Unknown Speaker
I know. There was one that was crowd funded, but I don't know if theirs was okay. But yeah, cool. And so that's what we've been doing this week. So I just will move right into the rapid fire questions or stuff we've seen. Oh, yeah. So did you see that project with that strand beast? That was the roadmap control strategies. So yeah, so strategies so like these? Well, the real ones on these giant things that walk on sand and they have moving linkages that are pretty crazy in mechanical
Host 3
kinetic art strange, almost organic beasts that that most of the time the artist has them walk across the beaches, and they're typically driven by wind we have by wind Yeah, he has some some crazy mechanical leg joints that just cause these giant I don't know they look like they're made of bamboo or something of that sort and they just crawl across the beach and get weird
Unknown Speaker
Yeah, the video I saw them while back was he they also react to like water and stuff. Really? Yeah, they had one at least the one that he had video is like crawl to the water and when the water hit it crawled back.
Host 3
Hmm. I guess I knew he was doing or at one point in time he was doing nothing but mechanical motion for everything. I wonder if he's added some intelligence to him now.
Unknown Speaker
Yeah. Or maybe it has something like it's like the water hits a lever and it causes the the linkage to go backwards.
Host 3
Yeah, it's it's intense. One way or the other. Yeah.
Unknown Speaker
And then at Mel, if you are microchip now came out with the 80 Mega 320 P B. Whoo. Which it looks like a supercharged version of the 328 P. So what do you think of that guy?
Host 3
Honestly, it's looking pretty cool. The first thing that I read about it is the fact that it has two more 16 bit timers which you know, double thumbs up on that for for timers on that the Arduino only had 116 bit timer, which is great, but but got to have that that timing got to have that that accuracy in there. And so that that was super cool.
Unknown Speaker
Yeah, I remember running into that issue a lot using Arduino and running out of basically timers.
Host 3
If I remember right, it has eight to eight bit timers. Yes, along with it and eight bit timings. It's great but now now with this guy haven't 316 bit timers
Unknown Speaker
Awesome? Yeah, the speaking of that only couple eight bits is the problem of eight bit is you don't have a lot of headroom to keep counting. Right. And I actually remember making a counter that a eight bit counter trigger to increase that basically, I made my own rollover counter. Ah,
Host 3
excellent. Yeah, while a couple months ago, I was designing a synthesizer with with an Arduino. And in order to get frequency control, like I wanted from, it was like a 10th of hertz all the way to 20 kilo hertz. I had to actually take my 16 bit timer and I had that roll over to get to get what I needed. So I so yeah, it's it's it was a pain but but it's cool now that we got this extra. A couple timers in there. Yeah. And
Unknown Speaker
then also has like more, you have another UART, which I think you had to use like a 644 P ATMEGA. To get to was like the cheapest you can get two yards. Yeah, something like that. But so now this one's got two yards, which is cool. So you can do you can do serial and do your your i square C on the same ones, which is cool. Oh, wait, no, it's actually separate to serial and to SPI serials. That's right. Yeah. Yeah. So you get you get double both a channel 10 bit ADC ad, which I think is normal and the regular one. But the cool thing here is also operates on the 1.8 volts now Yeah, which is really cool. And apparently it also supports 24 buttons of built in capacitance, which means it has support built in for capacitive buttons, like on your fancy appliances and that kind of stuff. That's cool. And it seems to be more makers are certainly use those those capacitive buttons because they're cheaper buttons are expensive, because they're mechanical devices. Basically anything that's mechanical on a PCB board is expensive. Yeah. And so having a capacitive touch button. Yeah, brings your price down a lot. Cool. also increases reliability a lot. Unless, unless the environment you're using the devices not working for the capacitance because I guess it's really dry. You don't actually couple really well to them. But yeah,
Host 3
cool, well, that actually, you know, looking at this the, with the voltage, the low end being down to 1.8 volts. Now that actually kind of brings up a question I got for you, Parker, if you had to choose one rail voltage to use for the rest of your design career. What would that be?
Unknown Speaker
Well, so this lock in forever for everyone? Like it sort of in the future can a company if a company goes we're only going to be 2.5 volts and it's like well now
Host 3
that might change a year No, no, no, no no. For Parker yeah himself, you could only pick one revolted for the rest of your life
Unknown Speaker
probably 1.8 volts 1.8 Okay, lower voltage, you get better power and you get faster transitions. So you can go faster on your on your data buses, and you get less transients so you much easier to pass you know, FCC CE testing. lower voltage is always better. Mostly unless you're transmitting power than you want high voltage. Cool. Yeah. And then so we had a couple of weeks ago we had atmail being bought out by microchip and before that we had Altera been bought by Intel which was interesting but kind of makes some sense well now there's rumors of Xilinx which was Atmos competitor rumored to be sold off and that's another you know, multi billion dollar company market cap
Host 3
given given given another couple decades and they'll all become one giant conglomerate of chips.
Unknown Speaker
It'd be called chip core. Okay, well, no mega chip Corporation. Oh, geez. So anyways, so it's gonna be buying Xilinx so there's no there's no, no one out there.
Host 3
What if What if Zeira bought them out?
Unknown Speaker
Host 3
Well, okay, you're at Intel. And then they crushed all their products together. So now you got microchip and Atmel and Altera and Xilinx you get these these titans out there.
Unknown Speaker
Well, so see who's O ti well ti bought national National Semiconductor a couple years back on I think that was less. They probably purchase other companies but that was the last big purchase. I wonder. I wonder if ti might be looking to get into the you know,
Host 3
i ti if you look at what Going into, they do a lot of all in one packages. Ti has a lot of chips that they're that they've recently released. And in fact, I've heard Gosh, it's been a philosophy of TI for many years now where they, they try to take one chip, that kind of does it all for a corner of the industry. Yeah. Especially automotive. They have one chip that just runs every sensor or every whatever you want in there. So I don't I don't I don't know if they're wanting to break into this. I think they kind of, it's not niche market for TI it's more like, pick an industry dominated with a single chip.
Unknown Speaker
Yeah. You know, or a single architecture. Yeah,
Host 3
right. Yeah. Right. Right.
Unknown Speaker
Well, there's, well, there's a there's also AMD, but I don't think AMD is in the position to be buying anyone given how bad their their market is going right now. Because they bought a ATI Well, I was like, eight years. Yeah, something like that. Maybe a decade ago, somewhere around there. And I think was about eight years ago, eight, seven years ago, they bought them out. So I don't think there are any position buying I can't think of any. Anyone that's exercised the cash left to the cash left. Yeah, I mean, I liked it. The Intel party doesn't have any, you know, cash floating around after buying at 16 points. For like $16 billion and microchip just plopped down. What was it three billions change?
Host 3
Yeah, it was it was something now. And
Unknown Speaker
Host 3
Yeah, it's S T is a big player in the game. Samsung. Yeah, Motorola.
Unknown Speaker
Oh, no. What's Motorola actually? So making?
Host 3
You know, I haven't looked in a long time. Honestly, yeah, I couldn't tell you what they make right now at all. Yeah, it's the thing that was like Xilinx has been around I've shoot I don't even know how long but but the Yeah, the name for example, with the the microchip Atmel thing. And Xilinx being bought out. What I'm wondering is, is the whole atmail thing going to just dissolve and they just don't even the name doesn't even show up anymore. And the same thing is Xilinx just going to
Unknown Speaker
gone? Yeah, well, it looks like Intel is going to keep Alterus name around. They have so far. Then basically, when you go to Altera website it says, it says Altera and it's like subsidy of Intel. It's like a tagline. I mean, it could be like National Semiconductor when ti absorbed National Semiconductor like National semiconductors datasheets are all wiped out. Like it's all ti stuff now. Everything got updated to like T eyes. naming scheme and stuff.
Host 3
Yeah. I like T eyes data sheets, by the way. T it has some good data.
Unknown Speaker
They have very good mechanical drawings of their parts. Yes,
Host 3
they do. Which we should talk about. This is something that Parker and I I talk about at work a lot. We need to have all data sheets dimensioned pins from the center of the pins or pin center pin. Oh my gosh, why can't people do that? Yeah.
Unknown Speaker
Um, so anyways, so yeah, Xilinx have been up for sale. See? Very interesting. See who picks him up? I think the only people in the market that has cash. The spend report VTi. Who else on the big players but St. Maybe I have no idea. Maximum? Yeah, maximum you can get by their chips. Oh, yeah. Actually the worst is Lt. Linear tech worse that way. Like, if you're like searching for a cool like apart like, oh, yeah, this chip does everything in does the dishes and like, oh, it's Lt. I can't buy it anywhere. Yeah, no.
Host 3
It's just not available. Yeah. Yeah. Each one has their own unique little flavor that they add in the data sheets. I've dealt with maximum chips, and had mixed results with them. But honestly, their data sheets are awesome. Yeah. And they just sheets, the thing about Maximus, they give really awesome examples in that data sheets. Like most of the time you pull up a TI thing. It'll be like, here's an op amp. inverting configuration was like great and my back in in school. Give me Give me like an application and Maxim will give you like 500 applications in a single data sheet. The next
Unknown Speaker
week the cool thing is on that notice lt is the same way they actually will like when you first bring up their product page. It has an application like schematic Yeah, they really cater to engineers that way palm is you can't pay their parts.
Host 3
Yeah, they're great. They're they're high fall. Yun players I guess they're the the onesie. twosie hackers Yeah, probably don't I
Unknown Speaker
completely void LT and maximum is kind of a crapshoot, depending basically with the tricky with maximum is when you look at the datasheet does it look old? If it looks old, you can't find that part anymore? Yeah. Oh, I think that we'll wrap up this podcast a little bit over time, but a random tangent. Yeah, so this has been the macro fan podcast. I'm your host Parker. And I'm Steven. Cat Till next time, take it easy.
