Episode 14 Transcript
Welcome to The Bootloader. I’m Paul Cutler. And I’m Tod Kurt. We have a special episode
today as we welcome guest Kevin Cappuccio, creator of the Jumperless breadboard. Kevin,
welcome to the show. Nice to be here. Thanks for having me on. We each have brought two
things to share. We’ll chat about each one for a couple of minutes, but no more than
five. If you want to learn more, visit the detailed show notes and transcripts at thebootloader.net.
Kevin, before we start, let’s talk a little bit about this Jumperless V5 that the crowdfunding
campaign is going on for. I made the original Jumperless about almost exactly a year ago.
And I hacked in this probe thing. So what makes the Jumperless V5 so much cooler is
I added a probe that lets you just poke out connections. And it was like, once I did that,
I was like, oh my God, this is the way to use this thing. It’s so much nicer. So I just
started over, you know, like used all the cross point switching matrix to make all the
breadboard connections in the back, kept that. And then, yeah, so V5 is just making it really
like intuitive, a nice UI to do whatever. It looks so cool. Like, especially with all
the LEDs behind each breadboard point. So like as you touch the probe, they light up.
It’s just, that’s great. Did you use these 446, I lost the chip now, the analog crossbar
switch that’s like 128 switches in this little chip. Did you use that on the previous Jumperless
as well?
Yeah. So like early prototypes, I was using an old Mitel 8816, MT8816. And so it turns
out, but they’re like big PLCC packages. They’re like huge, like ceramic heavy chips. So I
couldn’t fit more. And so I went looking, turns out the CH446Q is kind of a clone, but
they like made it a lot better. Like it’s kind of cool to see companies doing that where
they’re like, they take the same thing and then they’re like, we need a serial addressing
mode. So like you don’t have to send a bunch of parallel data and run a bunch of wires.
You can just, so yeah. So I use those. They’re great. I use them way on spec too.
Yeah. I’m a big fan of these analog multiplexer chips to like basically let you turn one analog
input into eight or something. And to see this cool, it’s got 16 lines on this side
and eight lines on this side. And you just connect any one to any of them and even have
multiple ones connected. It’s just, it’s kind of blew my mind. It’s like, ah, why don’t
play with this chip for something? I don’t know what yet.
Yeah, they’re great. They also make a five by 24 version, like if you want to like really
fan out, I don’t know if I’ll be used for them, but I want to.
So the other, the other difference in the jumperless V5 is it’s got the new RP 2350
chip. Have you liked that chip? Cause this is one of the first designs I’ve seen actually
use it.
Yeah. So they make it in a bigger package so you can get that extra GPIO was so clutch.
Like it, I had a GPIO expander on there. It was like driving the chips and it’s like,
it’s so nice to be able to take that out and just, you know, instead of sending an I squared
C message to it or something like you can.
It was a lot simpler.
The, the beta test units that are out right now, like those were handed to me as samples
at Defcon, like cause they launched it at Defcon. I was like, no way I have to do this.
And like, yeah, just spent all of Defcon reading the data sheet like a couple of times over.
Yeah. I was wondering where you got the 2350 because no one else has them. And I was so
shocked to see a new product with them.
Yeah. I, I was one short for them and I bought a Pimoroni like a board with it on and just
de-soldered it and put it on there. Yeah.
Yeah. Cause I think, I think Pimoroni is the only place you can get those, the bigger version
of the RP 2350 I think. Yeah.
Yeah. It adds some like it’s, there’s like, you know, more pins, more ADCs and stuff,
but like really it’s just cool. Like I just did it cause I was like, ah, this is going
to be awesome to have the newest, newest chip on there.
Totally. Well, I mean it’s, it’s a good marketing move, you know, even if you don’t need the
extra CPU power and stuff, it’s just to say, Hey, I’m using this new shiny new chip that
everyone’s all agog about.
Yeah. I mean, and it just gives us, eventually we’ll probably need that room cause keep getting
all these app ideas in the discord. Like we should have a Python REPL on it. Like, sure,
why not throw that in there? Like we got so much room.
Do protocol decoding or something.
We do that. That was actually this entire week we were doing protocol.
Oh really?
Serial pass throughs. So now I can like, there was an update that just got sent out on CrowdSupply,
but yeah, we were like screwing with it for like this last week straight of getting serial
pass through so you can route UART lines or any like, or I squared C or something. And
then anything that comes in through the second USB endpoint, we’ll just get like bi-directionally
pass straight through. So you can put like an AT tiny on there and you can just flash
it as if it was plugged in by itself. It’s kind of cool.
Oh man, that’s cool. Yeah. Cause normally you got to pay like a bunch of extra money
on your, on your scope to get protocol debugging. And if this is like, this is part of your
breadboard.
It’s not as good as a scope. Very set expectations right there. It does a lot of things. It does
not do any one thing really, really super duper well.
Once the, the, the probe thing came out and you’re touching stuff and lighten things up,
I’m like, okay, this has got to be a synthesizer or a synthesizer interface device or something.
Cause it looks like something out of a sci-fi 1970s rack mount synthesizer thing.
I was going to sell a second synthesizer version, which is exactly the same thing, but twice
the cost.
Hey, now for those at home that might be curious, how much is the jumper list? V five?
It’s 350 bucks while crowdfunding is going. And then as soon as that’s over, which by
the time you hear this, it will be, then there’ll be three 79. Okay. Well, I’ll make sure that
we’d link to that in the show notes too. So people can check that out. Totally. Yeah,
this is very cool.
What’s the first thing you brought us this week, Kevin?
So I brought the Uno plus plus looks kind of like a regular Arduino Uno, but every pin
has an led on it and it tells you the state of each of those pins. So like if it’s, you
know, pins high, that actual row is lit up and how he does it with the actual like plastic
header is it’s a clear plastic bit and it acts as a light pipe. So like it’s not just
an led next to the header that’s lighting up. It’s the whole part of the header lights
up.
That’s pretty cool.
Yeah. Something like this. Okay. If I had just seen it and I didn’t see the schematic,
I would not trust it in a million years. Like the easy way to do this would be put another
microcontroller on it and then just read all those inputs and then send it to some addressable
LEDs. But John talked to him, he can’t program. So he instead did it the cool way and did
it with comparators. And so it’s a ton of, you know, quad LM three, three, nine comparators.
They’ve been around forever. And so like that, I would trust, like if I see if that’s on,
there’s really not much that could go wrong. That would tell me the wrong state.
Yeah. And it buffers it. So it doesn’t impact your use of the GPI.
Yeah, exactly. And he even like set the comparators, right. So like with the hysteresis, like,
you know, they won’t go over 1.8 volts what they’re supposed to. Yeah. It’s cool.
That’s awesome. Did he get like custom headers made instead of the black plastic, they’re
clear light pipes or?
Yeah. So I was, I was just talking to him and what he was doing was doing a clear 3d
printed, transparent, like resin, and then having a second 3d print that slots into it,
like really thin little blades that keep the light separated from one to the next. So it’s
got a really tiny channel, but JLC now, I was just, just looking on JLC the other day
and they do like full color resin, like clear resin, and then you can put color inside it.
So now it can be one part. Yeah.
That’s pretty neat.
Yeah.
Wow. So is this a thing you can buy or like, is it, does he, does he have also a crowdfunding
campaign going?
No. So he’s, he’s close. He’s getting there.
Ah, cool.
I don’t even think the Hackaday IO project that I linked, I don’t think that has all
the newest things. I think he’s now using full color PCB, but no, it’s, it’s coming
up soon and it’s, it’s going to be rad.
That’s awesome.
Hopefully I can convince them to make a Arduino Nano version. That’s going to be so much harder.
Oh, because then that will plug into the jumperless board.
Yeah, yeah, exactly. I mean, like it sounds like a little beginner learning tool, but
like, you know, like 99% of my debugging is, is this pin actually doing the thing I want
it to like, is it the, is it the pin or is it the code or something, you know?
Like 90% of the times when I’m helping people with coding projects, I just tell them, put
print statements like in between every line so you can see what’s going on. And they’re
like, Oh, and it, but like, you can’t do that because it’ll slow down your code or, or it’s
just like unfeasible having LEDs, like physical representation of what’s your, what your circuit’s
doing is like so much more clear.
Yeah. It’s funny walking people through debugging stuff and you’re like, no, no, check again,
check, check that that’s up. You know, like, no, the code says digital, right? Hi. And
you’re like, no, dude.
Not really. You didn’t set the pin to an output or something. Very cool. I can’t wait to see
more of this. Uno plus plus and it’s spelled P L U S plus sign. Yeah. It’s hard to search
for if you don’t know that.
I actually genuinely thought I was going to lose the Hackaday prize last year to that.
Like that was the project I was like, that’s cooler than jump for this. Like I would, I
would vote for that over my own.
I don’t know. They’re pretty, they’re both pretty cool. All right, Paul, what’s your
one for this week? Mine is the Manyfold app by James Smith. Manyfold is an app that’s
been around since 2021, but it’s been in the news recently because it just added activity
pub integration, which I’ll come back to in just a minute. It’s a self-hosted app built
to manage and organize your files related to 3d printing. It’s open source released
under the permissive MIT license and written in Ruby on rails.
Imagine printables or thingiverse, but self-hosted. You’re not locked into another walled garden
and it has some really, really neat features. You can run it as single user or multi-user.
So if you’re running it in single user, you’re just keeping a track of all the files that
you have multi-user. You can invite other folks to join your server, almost like pixel
fed does for sharing photos. I mentioned earlier that it’s integrated with activity pub. That
means it’s on the Fediverse. Imagine being able to follow a creator or a model directly
from your mastodon account, which I think is really, really cool. So every time that
that model is updated, you’ll get a notification. I believe I need to double check that.
And then one of the other cool things about it is it doesn’t just handle the 3d printing
file formats like you would expect, such as step files, STL files, and 3mf files. It handles
everything related to 3d printing. Every image format is supported from JPEGs to pings to
GIFs to SVGs. Video files are supported if you want to show a render of the 3d printing
model that’s going to be printed. And it can keep track of all the text files that go with
it. So if you have installation instructions, for example, it’ll have all of that built
in like you would expect it to. If you want to learn more about it, I’ve linked to an
interview with James and the Floss Weekly crew on their podcast. You can check it out
at manyfold.app and there’s a demo server at try.manyfold.app to see it in action. It’s
really, really neat. I highly recommend it.
That’s cool. I love seeing more things that we think have to be monoliths being added
to the Fediverse in some way. Because like, why not? Especially for something like Thingiverse
and printables, you know, fundamentally it’s not that hard. It could be an FTP server.
It could be. But, you know, if you’re running one of the servers, one of the things you
might need to think about is copyright violations, right? What if you have a file that’s copyrighted?
Or I think James mentioned in his podcast that he buys or subscribes to Patreon creators
who if you subscribe to them will give you files. Well, you’re going to want to make
those private, for example. You don’t want to make those public because those were for
sale and all that functionality is built right into Manyfold.
And just seeing updates. Like, you know, sometimes you get a file that someone made and then
you forget that like maybe they tweaked it, made it better. I don’t know.
Exactly. I think that’s one of the coolest things about it being on the Fediverse like
that.
Yeah. And back in the heyday of Thingiverse, one of the things I really liked about some
of the models is the discussion that was going on on a model. People were like, oh, you know,
what’s the right way to print this? And there’d be like discussions on like, you know, different
filaments or different orientations of the part or whatever.
And like if it’s kind of part of your Macedon experience, that that conversation can happen
pretty seamlessly, I would imagine.
Yeah, I don’t know if that’s enabled, but it’s definitely something to check out.
Yeah.
All right, Tod, what’s your first one for us this episode?
All right. So some of you might have already seen this, but to me, it was just like kind
of a little bit mind blowing. Like we’ve all seen the Doom game ported to insert tiny electronics
like the watch or the little Arduino or something, but…
Or the jump.
Yeah. Oh, is it going to have Doom?
And that’s great. You know, it’s like a really complicated game engine compared to like things
like Pong, but it’s not true 3D. It’s more like a 2.5D where the enemies are just sprites
and the level geometry is just perturbations on a 2D plane. But the game Quake, which is
the game that came after from id, was full 3D, fully polygonal monsters and objects in
the world, fully polygonal game world. And I figured Quake would never be part of these
little tiny embedded things. But I saw a couple of days ago that people at nexthack.com got
Quake running on a SparkFun Thing Plus Matterboard, which is a feather format board, you know,
9 inches by 2 inches. And it’s only got… It’s a 39 megahertz little board that’s got
256K of RAM and 1.5 megs of flash. And this is the same specs as the RP2350 pretty much.
So, you know, are we going to see Quake on the jumper list or on an Adafruit feather
soon? So first they started with a SparkFun board and made a little sort of prototype
that you can build yourself. They’ve included all the source. But then they created their
own gamepad PCB that houses an Arduino Nano matter. Like this uses the same chip, this
MGM240 module that has a Silicon Labs EFR32MG24. And it’s some Bluetooth matter chip that’s
pretty cool. And they got this whole complete package that has a screen, has the Arduino
Nano on it, buttons, sound output, and it runs at 35 frames per second at 320 by 240.
Oh, and also you can do BLE based multiplayer with someone else with the same board.
Oh, that’s amazing.
Yeah. And so like, like as someone, as someone who sort of, sort of got into PC gaming by
buying the 486 with the 4 megs of RAM minimum and like having that be such a stretch back
in whenever it was. And now to see that, oh wait, they could have done it in 256K of RAM.
It’s pretty amazing. In the show notes, we’ll have links to their multiple posts they have
on this, a write up from the Silicon Labs tech blogs. They really liked it. Links to
the design files if you want to build your own of these boards. It seems pretty doable.
I love this project. Quake always has a special place in my heart. I was a big gamer in the
mid nineties or starting in the mid nineties. And I had a 3DFX Voodoo card. And I, one of
the top five gaming memories I still have is the first time I had that card in my machine.
And then Quake, you walk up to the puddle and you see a reflection of the character
in the puddle in full 3D. Something else still never forget, because it was just mind blowing.
We didn’t have graphics like that until that card and that game came out. So it’s, it’s
pretty neat to see how far that’s come in the last almost 30 years.
Yeah, yeah. For me, one of my one of my memories that comes back unbidden to me is being able
to bounce the Quake grenade gun grenades around the corner to kill monsters and the noises
that it make of the “dunk, dunk, dunk” because it bounced around. It’s just like, it’s like,
oh, you can like kind of think strategically in this first person shooter game.
Like what if someone came back in time and told you that like that chip is a smart light
bulb or something. Yeah, it’s easier to just put that whole thing, something more powerful.
Yeah, yeah. It’s like, it’s like I saw seed just came out with a Xiao format, like a cutie
pie format board with the same chip for like $7. And, you know, like you’re not going to
be driving a really like high res screen with that, but, but hey, maybe it could run Quake.
All right, Kevin, what’s your number two for this week?
Yeah. So this one’s not really, it’s not a project. Like I’m, I’m bending your rules
a bit, I think. But it’s, it’s a field. So like the field of evolvable hardware, it’s
literally as old as I am. So the first project with evolvable hardware was University of
Sussex, Adrian Thompson. What he was doing was, oh, in 1990. So, so what he was doing
was like getting an FPGA. So I think he was using a Xilinx XC6200 and basically giving
it a fitness function. So I think the first, the like the seminal thing that he did was
a tone discriminator. So being able to tell the difference between one kilohertz and 10
kilohertz on, I think there’s a hundred gates, it’s like a 10 by 10 FPGA. And yeah, and so
he would just say, is it okay at that? And then it would give it a random bit stream,
just random arrangement of a bunch of logic gates. And then, you know, at first it’s probably
just kind of up in the air of none of them are doing the right thing, you know, but then
over time, you know, he’s doing like an evolutionary thing where he’s like the two most fit ways
of getting, you know, making this pin go high at 10 kilohertz and low at one kilohertz.
Do that again, you know, and then put some randomness in it. And he ran it for a while
and it worked. Like it just found, and it’s like, if you look at the, you know, the arrangement
of gates, it’s complete nonsense. Like there’s parts that are not even connected to anything,
but are necessary for it to work. Like it’s using kind of just like the weirdness of like
signals going, like, you know, there’s no constraints. We don’t have to like, you don’t
have to abstract anything. So it’s just like, yeah, it’s using, and it probably wouldn’t
work on another one. Like if you put that exact same setup, it wouldn’t work on a different
chip because it’s just, but yeah. And so running circuits like that would be, I don’t know,
I just think it’s the coolest thing ever. But yeah. So what happened though, was why
I feel like it’s kind of relevant now is they stopped using it. Like they discontinued the
Xilinx XC6200 and now all the FPGA bit streams are like encrypted. They’re like all, you
know, they’re very proprietary and what you need to get this to work is kind of just a,
I know one-to-one of, if I say top left corner logic gate, be that, it’ll be that. But what’s
cool now is I hope that there’s a resurgence in this because the, have you heard of a project
Ice Storm? I have not. They’re kind of, they’re like, they’re reverse engineering the bit
stream of a lattice FPGA, like a modern one. Okay. And so like we had 30 something years
of like, basically this whole field is kind of dead. Like there’s just wasn’t like hardware
for it. And then, and only now, like we can pick up again and people can screw around
with trying to get, you know, is it the best way to do something? I don’t know. Well, I
have to imagine too, it’s a lot cheaper now to do it than it was back in 1990. Oh yeah.
Yeah. Yeah. There’s a little, there’s a little ice 40 FPGAs are pretty cheap. I see them
pop up on various Arduino looking boards and stuff. So, and if, and if it’s just, you know,
set it up and let it run and call me, call me when you figure it out. That’s pretty great.
Yeah. I think there was some, there was some interest from like space stuff. Cause if you
broke your FPGA, like physically broke it in half, you might be able to get one that
runs on just the rest of it. You know, that’s yeah. Yeah. It’s like, how do you make, how
do you make resilient circuits? Like right now we design things very sort of cathedral
where like every bit has its own important part to play. And if one bit is missing, the
whole thing doesn’t work. But if we can make something that can recover, that’d be pretty
great. And fun fact, uh, in the book, 2001, a space odyssey, that’s how Hal was programmed
was like, he described some process just like that, where they, Oh wow. So jumperless, like
the first idea of it came after me going on this rabbit hole for like a really long time
about evolvable hardware. And it’s, it was kind of frustrating cause it does it like,
you know, there’s a lot of work on it and then it kind of just fizzles out, you know,
cause they discontinued the chip and it was like other universities weren’t able to screw
around with it as much. And yeah. And so that was kind of part of my thinking of like something
you could do with this whole analog cross point switch away array is you could like,
it’s not going to be a feature, like you would just be able to run it and it would try to
fight a circuit, but as a thing to screw around with, it’s that’s pretty cool. Good for that.
Plus on the jumper list, it could look cool because you could have the LEDs represent
the connectivity that’s, that’s evolving over time or something. Yeah. All right. So, uh,
Paul, what’s your second one for this week? Uh, my next one is a current Kickstarter project
that’s going on for a few more weeks for the FlexiPi. It’s a new Raspberry Pi Pico format
board, but it’s wafer thin and it’s flexible. Hence the name FlexiPi. It’s got a few upgrades
from a normal Raspberry Pi Pico. It uses USB-C. It’s got a Neo pixel built in. Otherwise
the pinouts stay exactly the same. The Kickstarter campaign runs through November 24th and it
includes three digital books that come with it. Getting started with the Raspberry Pi
Pico, a micro Python book and a circuit Python book. They’ve already reached their funding
goal that their goal was $500 and they’re over $7,000 already. But if you do back it,
remember it’s a Kickstarter, so nothing’s ever guaranteed, but it’s really neat to see
how flexible that really is. And I don’t understand how they got it so thin, but it’s something
that I want to keep an eye on going forward. Yeah. Flex circuits are pretty cool. I it’s
like, this is, this is really impressive. I don’t know exactly how I would use it. I
mean, I don’t really do much flex stuff, so wearables are the first thing that came to
mind for me. Ah, yeah, definitely. Definitely that. Yeah. Yeah. Someone actually dropped
that on my discord just a couple of days ago and it, yeah, it’s funny cause I can’t think
of what to use it for, but it’s really fun to think of situations that it would be useful.
Yeah. There’s so many, like what weird problem you’re having really like, Oh, I need to just
wish this Pico could bend. Exactly. And I should mention it’s, it’s $20. So it’s, it’s
not cheap compared to a normal Pico, but that’s what you get for having something that’s that
so thin and flexible. Yeah. Yeah. And just having a little bit of give on something that
you wear could be all the difference. Like it doesn’t have to bend much, but maybe just
a couple of degrees could make it not be like, Oh look, he’s got a piece of technology embedded
inside of his hat or something. Right. All right, Tod, wrap it up for us. All right.
So my second thing is the EMMG MIDI synth and is created by a hacker in our sort of
larger community. It’s got a name Jonathan Bisson or B. John J. It’s a board he created
as a teaching tool for a workshop he gave on MIDI and music synthesis at the pumping
station one hacker space in Chicago. In the show notes are links to the presentation and
other, other aspects of the project. The, the workshop taught what MIDI is down from
the signaling level to how it’s used by performers. Each student of the workshop got, got one
of these custom design boards. The board has eight pots, 12 cap touch pads and OLED display
and stereo out all driven by a Pico clone. That’s a USB-C 16 megabyte version. The workshop
also talks about how the GPIOs work on the Pico, how CapSense works. It was like, it
was pretty fun. And the board has a secret mode by default. It comes up as just a MIDI
controller, but you powered up one of the switches held down. It also is a full synth
using this interesting Prof32U synth engine for Pico that he found. And he was able to,
it’s like an, it’s like an Arduino chunk of code. But it’s really cool. It’s got like
four, it’s like it’s a paraphonic polyphonic four voices with built-in chorus and delay
effects. Really, really cool filter. It sounds pretty good. Selfishly, one of the reasons
why Bright bring this up is because I have one. He sent one to me. I was literally just
about to ask you that. Yeah. He, he based the design of this board on a couple of my
previous projects, most notably the Pico test synth, the Pico slider toy, and this sort
of unreleased thing I have called 8x, which is a sort of eight pots to one analog pot,
sort of expander board for, for microcontrollers. And his board, by having eight pots instead
of two solves one of the biggest problems I’ve been struggling with, with my little
Pico test synth as I try to write code for it for people. And that’s having only two
pots when you need to control a whole slew of values is a real pain in the butt because
you have to keep saving the state of where the pots are currently when you switch which
parameters you’re changing. And so, and then you have to like deal with the fact that like
when you come back to that parameter, the current location of the pot is not where the
pot physically is. And so you have to like deal with like knob what’s called knob pickup
and stuff. It’s just a real kind of pain in the butt. So with eight pots, you can like
have immediate control, a bunch of parameters without having to do a bunch of page switching
and stuff. I think if I were to redo the Pico test synth thing, I would have either more
pots or use rotary encoders, which is why you see a lot of rotary encoders on things
because they’re incremental. You just show the state immediately and just any turn of
the knob will just increment or decrement the state. All of the designs for the board
and for the workshop notes and presentations are up on GitHub and I’ll put links in the
show notes. He also has a really great sort of blog post that describes his whole design
process including like the DFM of like how do you make this thing actually buildable
and also the open SCAD CAD files for the custom knobs he made for the board. It is pretty
nice to get some sort of like free stuff back for all the random little circuit boards I’ve
made over the years.
That’s pretty cool. And you said it runs Arduino?
Yeah, his like the main code he has is Arduino. He also he’s also got some experimental stuff
for CircuitPython, but he started down CircuitPython route but wanted to have something that was
like was easily able to switch between these two modes and he wanted this with the synth
engine that was based on Arduino.
I love the idea of making a board for a workshop. Like because now like the person giving the
workshop knows exactly how that board was made. You’ll never run into a question of
like, oh, why is it like this? And they’re like, I don’t know.
Yeah, I wish there was video for it because I kind of wanted to know like how did he have
everyone hook up the boards like were they all controlling like a synthesizer in the
room or something? I’ll have this in the slides and I haven’t asked him about it.
Just probably like a loud mess in that room.
I know.
Each person doing their own.
Well that’s our show. Special thank you to Kevin for joining us this episode.
Thank you so much for having me. That was fun.
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and until next time, stay positive.