Hi, it's soldiering time. We say again. yeah, we're gonna do some soldering. What are we going to assemble? Sagen Computer: A computer.

What's it called? I say 2014 Mini I See Yeah. I'll see Stan So I don't know. Anyway, Yep, it's a Z80 computer. Look at that.

It's a Zed AV computer. old-school the Z80 processor. Sagen. That's the brains of the computer and that comes from 1976.

Yeah, that's how old it is. Okay, so it's a really old processor on it and we're gonna make it. And to talk to this computer. it doesn't hook up to a display.

We have to talk to it through another computer through a serial cord. That's weird, huh? Yeah, All right. so you're gonna solder this. And where's our chips? We've got our chips.

Yep. So we got our chips. Where's our capacitors? yeah, and our resistors and other stuff. Yeah, And now sockets? Yes.

I See sockets and connectors? Cool. Hopefully Daddy will not make a mistake this time. What? I Don't make mistakes. Solar even made a mistake in the solar room.

Dude, you never gonna let me forget. Are you I missed one? All right. let's go. All right.

So first thing Sagen, the most fun thing. The sponge. We have to wet the sponge. Yeah, thickest old is going to be easier.

I'll try and find it. There you go. You always have to no matter how good you are at solder, and it always takes a few joints to get back up to speed. You've got to make sure the flat part of your iron is flat on that pad so it conducts all the heat into the pad and the pin that you're trying to solve.

And then once the pad and the pin are up to temperature, then your feed in your solder and it'll just flow like butter around the pin and the pad. Yeah, chori. Find a thicker solder after the big slider. It could be any way they might want to give you tip of white from the onion sponge.

Four more left, one more to go. Just leave your iron on the joint for a second and then start feeding the solder in. And if you feed a consistent amount on to each joint until it's sort of like a nice shiny Filip Perfect. Yeah, that one pesky bored rocking around.

That's right. a gun. All right. Yeah, yeah.

Oh, so it would be easier. Can we say again? Yeah, not after the big spoon not thank-you lunch. So this is 0.38 millimeter solder. It's about as small as you can get.

Yeah, it's not really designed for screw holes. Yeah. and I use a point tree I'm lead person for my paces so this is the exact same size my leg that I use it was five millimeters. Yeah.

I used to play 5m going three, sometimes four five. Did you know that this solder saying inside it? even though it's very thin, it has five different cause of flux inside I Know I can see that Yes, that's quite cool flux motif or soda? That's right. Multi core solder is genuine multi core brand so it's got five cause of flux and flux helps you. helps clean the joint before you when it goes on.

It helps clean it just in case it's tarnished without any other any other thing on it because his soul adjoint astonish. then the solder doesn't taste very well I just going back and doing a few I yeah yeah he with nice older and is just trying to learn how to put a consistent amount of solder on each joint. practice with only one God Yeah I know exactly yet cuz we didn't practice before this and this is I knew the second time is sold it isn't It's a shame my whole life and I am I'm really you're really good. You are pretty good.

Sagan At the comments on the previous video of you soldering, everyone said that you were much better than some of the other youtubers out there and so I'm much better than Danny way my other state. Oh thanks dude we're never gonna forget that There we go. That's getting me good. ha.

Beautiful flow on there. awesome worksite. Last ride. Yep that's right.

One more yeah, give it a give it a wipe after each road. Yeah I Think you would do a lot better with the thicker solder I'm sure you would. It's thin stuff. It gives you more control because it can control the amount of solder that you're feeding you.

But you do have to feed in a lot more and generally it's harder to make get in there and make good thermal in the initial thermal contact with your pet. So because solder just yeah, it's going to be nicer in that respect. the flux is more exposed to. we went lame out soda.

Will we say I'd Like Mr. Solo That man and how old are you sayin? Seven and three who is seven and three for how long? How old are some of those are they give? Those of us older is out. Oh these are the YouTube is they're in their 20s and 30s. For most everyone reckons you're better.

Sagen give us a thumbs up. Yeah, how you doing That's it. Quick because some that soldering is a different experience every time. You use a different solder in iron which you haven't used this one before and a different tip.

I Don't think you've used this particular tip before. And the type of solder that you use, you know? Yeah, this is lead-free so this is not as easy to solder with as lead. You'll find that with leaded solder it would be much easier, but my mom would not let me know she wasn't. Well, if you learn to use lead-free if you can do good soldering with lead-free solder, there's no reason to usually.

Really? Yeah, that's a problem with this little stuff that just kinks really easily and you're always going to straighten it up. So yeah, every time you solder is actually different. unless you're using the same thing all the time, which we're we're not doing enough here to use the same setup every time, don't He's always got a different setup every time you come to the lab. don't I Always changing labs.

Always changing. Yep, and when the flood happened, it was a complete maze. What's a maze it was. How do you like that Pace soldier and ion we're using a pace one.

Does it feel good? Really feels better than the Hakko that we use I think we use the hey Cohen last time. All right. Sagan Likes the pace because you see how that the tip is really close to where your fingers up and that that helps you keep better control the closer the tip is to your fingers. then find a control that you're going to have to close even though you can open your fingers.

you don't want that one on the end a mist. I Love the one the one the only thing expunged the expanding sponge is pretty fun. Yeah, looks like some somebody well you holding that solder a long way back. Must haven't you to control the solder if that's in the distance.

It's very impressive saying I'm that's why I'm whose territory I would fit the resistors next because they're low profile because what what you don't want to do is put in like a really high part and then you bought a wobble. You can't sit it flood anymore. So anyway, let's have a look. Say it.

This looks pretty good. Nice work dude. Are we yeah what? We finish this. I'm gonna do my happy dance happy dance I Got a happy dance order and happy dance.

Okay, you want to do your happy dance now? Yeah, all right I want you to put these two 22pf capacitors in those two holes there? I Think oh, you're game by myself like I did yesterday. Okay, now what you do is you put your thumb on top and those so they don't fall out. flip it over and just bend the leads out slightly. Gotta get inside those lemon squeezy easy peasy lemon squeezy like I said Mr.

Psyche of Errs to cut them off. how you do side cutters. Okay, you get in there and then you just tilt it to the side and then snip it. but keep your finger over there like that otherwise it could fly off.

Yes, it flew up. You got to keep your finger on it. Yeah, you lost it. I Think that's our first pin.

The brand new carpet. Well these instructions are pretty good. Look at these Sagen. It's because it didn't have the resistor values on here, just said r7, r8, etc.

So we would have had to consult some tiny little schematic which was there to find out which values what. But if I already have it down there and they have a picture The resistors - 22 K 10 K 1 Meg 2 K 2 So I want you to find all those different values? Here's our resistors here. These ones are all one value. They're all one value.

That's right because they're all on the tape so one case and they'd be 1 K so 1, 2, 3, 4 Yeah, we've got 4 of them. So what you want to do is just hold hold, hold these here like this and just pull off that tape. So what you want to do I'll show you the trick to this is you want to hold it like that and then sort of like just then like that that should be. It leaves a little just to fill it over there like a radius over there and that you'll find that that should fit almost perfectly I look at that into there, then down and should find that that's almost the perfect radius.

Make sure they're all in the same direction - - not that they're not that it matters, it's just a nice thing to have them all in same direction. What you want to do is just bend the leads out just a little bit. Like that. Yeah, display them out.

You'll find that been that you did is a most precise not point. four inches pin spacing. Cool. One of them knows how to thank you.

Yeah, it was hard to get you. She's all. tip on the pad on that side there. Yeah, you've got to come in at a different angle.

Maybe maybe you want to flip your board around like that. So that yeah, yeah. if it fit for these ones on this side. Yes and that angle is going to be the best.

But for the other ones, you always have to sort of like move your board around when you're doing things like this. No Kings Cross over these two lies. Price? That's alright. See now now you might want to flip it around like that.

See just PI 0 What's Pi? 0 Oh, you're right. Yeah, that's for the Raspberry Pi Yeah, we've got one. We've got a Raspberry Pi Yeah, we want a red red-orange but there's four colours there. It is ready.

Yes, there is. The one at the end Is the tolerance you lose each day? What color is it? Gold? Yeah. Orange juice. 17 Oscilloscopes That's crazy.

Who has 17 oscilloscopes? Yeah, that's crazy. Why? Why do I need 17 oscilloscope? It's crazy. No plus one through. There's one at home.

Yes, Exactly. Got iDate Oscilloscopes? That's not. And Huxley really likes that there man oscilloscope at home? you guys doesn't me? Yeah, he just presses all the buttons like that's really sharp. Yeah, there's a really sharp fine point tip, right? Because if you want to do really fine surface-mount soldering, then you would use the fine tip, That's easy as what.

Sagan also stands for something else that I learnt at school in year two. really acronym for something? Yeah, so pay is persuade and P I is entertain and eight right now evens attained an eyes inform their free purposes of the author trying to tell you in a book. Oh, it's persuade, employed or entertain. So they can entertain you in a book.

They can persuade you in your book. Or they can inform you in a book that's really deep. How does it look? How does it look look at those my fantastic joints? Yeah, I can look at those beautiful. What do we have to do now? So you get the offcuts of our resistors and do them as links loose.

Seriously, this is crazy I don't know why we have to do is we have to put links in it. It's not for PCB layout reasons. Maybe it's for experimenting and jumping later. Maybe it's life setting, memory addresses, and stuff like that.

It's really tricky to get those really tricky. Alright, - yeah, four more down there now. I'll tell you the trick to these. Say him because they're all flapping around in the breeze there.

What you do is you put the jumper links on them to hold them all together as a big group. You see how they're all a big, solid group now, so it's much easier to actually keep them all in place like that. I do ones in the opposite corner first and once you've done those - okay, well, you shouldn't have to hold the board anymore. Is this a file? Is this a file? I Think it's a file.

Say again. I soldered a pendant where you soldered. but I put it on there a pinhead I was supposed to have a socket instead of a pinhead up. Oh Actually, that wasn't the FTDI interface that was the keyboard interface.

so not that we're going to use the keyboard interface on this anyway. so we're now. saw her in the right angle. FTDI Pin header which is a pin header.

It's not a socket, is it? Sagan Oh, just think now we're gonna monster 40 way hitter Sagan Good work there Sagan Yeah, you got more consistent near the end. Feeding a little bit overzealous is only it'll be too much solder on a couple of us, but it's behind. Dave Well done. Okay, we've got a power socket and a switch, so four of those and three joints.

There's their big hole so you gotta have to feed in a lot of soda with 23 5 millimeter solder. Lucky lost the bypass capacitors. Say yeah, we probably should have put those in still second, but it doesn't matter. So do you call a lender or an LED So you need lead? Yep, there's always one that you miss every time, guaranteed.

Okay, so you can I think what they actually provided us with was right angle 40 way a stroke. We put in a straight 40 way and we've got a socket 40 way as well I Think it doesn't matter for this, it'll still work. but this is actually going it. There's like a daughter board and you can plug in multiple boards and stuff.

And if you're going to do that I think the right angle was the one to use so we we didn't actually have to solder in that 40 way. but that was fun, Wasn't it? Yeah, cool. Let's plug the chippies in. So and because the pins, you can see that they're sort of splayed outwards.

Oh, they're not straight. We have to actually bend those and Daddy will do that because it requires a lot of force and a deft touch to get them. Now do they look straight now? Yeah, all right. Daddy's got a good eyeball for that.

Now we have to get pin 1. He's over here. See that notch has to match to that notch. And these are jewel wipe sockets because they have see a contact on either side.

So they're called jewel wipe because they wipe on both sides of the pin. We've got a 68 B5 Oh What is this one here? Number 183. Well, it's actually it's that number there. Yeah, there's lots of stuff on here.

It's actually sixty two to five six. So can you find the sixty two to five six on there six There. So wait, wait. you got to get pin one right.

Notch up there. Not there. Okay, What you do is you get sort of on an angle. get ones all the pins in one side first, all in one side first and then that.

Yep, push it down. Excellent. This will be our wrong. What's so wrong? A read-only memory.

It contains all of the instructions for our computer and these are our TTL chips. You can ask me what TTL means. Isn't it transistor transistor logic? It's much quieter without that fan, isn't it? Yeah, and we're ready to power up. I Think we want FTDI power.

We're going to put the jumpers in so we want if the power to come from here and it says set the keyboard jumper to PI or serial depending on what input you want. Serial connect jumpers to the ground position. For basic, we want basic to ground to the ground zero a position ground. Okay, so that will set the memory address.

You want to put that on there little jumper links that will set the memory address for the ROM so that when this when the process of boots up, it will know it'll read from a certain memory address in there and there'll be instructions and it'll run our basic programming so we can do some basic programming. What? What language do you use at the moment? Um I used to block language. Um scratch scratch blocks and yeah, a graphical user? Yes, yeah, but we're gonna use a command-line programming language called basic and it's pretty basic. It says InDesign that's it.

Alright Sagan our lids on. Look at that. Beauty And so a parent at Five volts from our F1 FTDI did cereal board and it's supposed to be a hundred and fifteen thousand Two hundred cereal speed. So let's get our terminal program calm.

Eight hundred and Fifteen thousand, Two hundred select. Ok and if Danny hasn't swapped and they transmit and receive lines which I do all the time, then I'll push it. Let me push the reset button. nothing.

Maybe I've swapped it I might have gifted. Hang on I'll just repair it. Nothing sayin. Oh, we're gonna do some troubleshooting dude.

Ok, so you can I can see here that it actually uses on the FTA it's got an RTS pin a request to send I hope it doesn't need that. So I'm just assuming that we can work without that nothing, daddy. Well, maybe all the right hands off at the top. Yeah, right.

But no, it, no. the curse is there. It should show up right where that cursor is. Sorry.

Good thinking though. Say again. Good troubleshooting thinking. Ok, so again, it's time for the big guns that's bringing out the oscilloscope because we're not getting any lights at all transmit and receive.

so we're not like seeing any data being transmitted from this receipt. So let's so there's our five volt rail. Ok, alright so let's maybe measure out clock. CLK Yep, but the clock is on.

These header pins are very nice. Oh hey, there we go. When you have a clock, there we go. It's got all these little over there called overshoots and it's got those because look at our big antenna.

Earth lead there. Okay, so that's naughty. but the signal is there. So we have a clock so that means our processor is getting its clock.

so what else is wrong? Let's measure the serial line. Okay, let's trigger that. Okay, let's do single-shot trigger and we'll reset that and bingo. There's our serial data.

Okay, captured. So our serial data when I push that button. Yep, the reset button. There you go.

Look, there's all that text which would come up on the screen. It should come up. So our computer is actually working. It's outputting all of this data so it works.

Dude, there's nothing wrong. You're soldering. transmit and receive. I May have goofed to transmit and receive not still can't see anything if I still look because you can see I'm not sure why this is not working Wow This computer is working because it's outputting the serial data and if we actually decoded that then it would we can decode that.

you want to decode it on the oscilloscope. Yeah, okay, let me show you it's the serial. This is nice. Where's the serial decoding? Oh, there we go.

Features I Did right. Okay, you got to go into what features and okay, did your frequency response analyzer. okay reference way from serial bus. There we go.

Doesn't have a serial? Oh that's why cuz I don't have a serial decoder installed. Oh I don't have the option? Say again. that's terrible. They haven't given me the option for a serial decoder installed licenses Sigma 2.

Memory Mask Bandwidth Waveform Gent. No. I don't have the serial license. fail.

Unbelievable. Thanks Keysight Wow Let's ditch this scope. Let's get another oscilloscope. Yeah, get our nice Rohde & Schwarz.

Look at this. It's big. This one's a Bobby Dazzler Sagan So we switch on our protocol. This one's actually touch screen we want UART which is cereal.

Ok and we want to configure it paradeen under today And what speed were we? A hundred and fifteen thousand Two hundred? Yeah, no parity. 1 Stop it. Ok, we should be able to decode that now. Tender 1 front.

Don't know why I was set to 100 to 1. Just make sure. Yep, Oh there we go there we go. There's our data.

So yeah you're right son. stop mode. Say again. there's our data.

Ok it stopped Ok I'm gonna do just move it all the way over here. it is that stopped it. it's run then again and capture. Ok 0 0 0 0 that doesn't look correct it so it's not decoding it properly.

So we need to go into our protocol decoder. Say again I was looking at the wrong bus and so what not to wait? We've got two buses turned on I was looking I was looking at the wrong bus. Don't be too we want like can we like turn decode off? There we go be one. Okay so there's our bus down there you can see.

can we make that bigger? Be nice to make that bigger. you can read it. Ok all right. Oh there we go.

We can make it bigger. So let's go right back to the start here. see what it says? It's actually got incorrect. Yeah it's got incorrect outta there.

Oh hi There we go. You were right before. say again. I think we had it.

Ha ha. Look we got it. you were right. Dude it was that high-low thing I switched it to low Z What does that say? Z ad SBC Single board computers e ad single board computer and if we okay you want to press the single-shot button again and the reset tada and you want to use this horizontal to zoom into here.

Ah there we go and use this one to scroll across. There you go and can you read it? What was by gee some SBC yeah that was the Z80 single board computer by Gr N. takes I crunch sadly and that's what's supposed to be they say LF is line fees cold or warm? Start There you go. We got it.

Say again. Now Computer works. Yeah well it should. It's good.

So all that. Yeah, there's just something wrong with our serial decoder here. Yeah on there reading or the all the connection of that. But now Computer works so you're soldering with spot on mate.

we know. Winner chicken dinner. Alright, say again. Yeah we used a different serial adapter.

different FTDI So I have no idea why the other one didn't work here. We go. What's the instructions? This is cold. A Warm boot.

If this shows up, press C for cold boot If this shows up. Yes Pressey C Memory top push return to allow all RAM to be used. Today's Nav Basic version Four Point Seven Be Copyright 1978 By Microsoft 1978 Dues 1978 this is running Microsoft basic with 32k of RAM Now we can have a basic program. So I'm gonna.

This is how you do a basic program. Okay you gonna put line numbers first. You can either have the one two three you can put any line number. Okay, we're gonna put 10 and we're gonna do I Mean can we do seal this? Let's do it.

Which means clear screen 20 print What? What? What would you like to say on the screen? Hello there, Not how I World Sagan Once Hello there. Okay 30 go to 20 You ready? Let's run our program so it'll print Hello there. Hello there, Hello there. You should Hello there.

That's our program. Break in 20 so we just press control-c to break that and we can list our program. Ok can we do Sandeep the see list I See a clear screen doesn't work. Okay, so what we can do is we can go 2015 N equals 1.

Okay, and I'm gonna count. So let's list our program again and 20 print n and 25 n equals n plus 1. So it should count now. So if we list our program okay, what it's gonna do is it's gonna go.

It's gonna make n equal to 1 Ends just a variable. Okay, so in Ds1 we're gonna print the value of n which will be 1 and then we'll go in equals n plus 1. So n will become what - of course not be held in a variable. You know all about variables.

Yep, cool. Awesome work, Dude, Here we go. What's counting up? haha cool. Can we do it? So that's a basic program? Say again.

Yeah, it uses line numbers like this and then instruction. so it's different to how you use your graphical join blocks together in scratch. Yeah, So Sagen we built LRC 2014 Z80 computer kit from 1970. Well, this is from 76 so 78.

Yeah. And we ran a basic program. Awesome. Took like 10 Troubleshoot says it did.

We had to troubleshoot it. We had to get a little serial adapter to get it working I don't know why the other one that was my old faithful Cyril adapter I Don't know why it didn't work I mean anyway we troubleshoot it on the oscilloscope and it said and it said the protocol. It said the we did protocol decode in it said that 80 single-board computer didn't it? Yeah and it worked. So how would you rate that kit out of 10? Is that fun kit? Yep, I'd write 10 out of 10 that for the RC 20 for it where you built your own computer.

Dude, that's pretty good. Wasn't a single soldering error on there. Yep, Yep. well done.

So that's only your second kit. Yeah, that's your second soldering kit. Awesome. Well done.

All right. What do we say at the end of the video? say again, catch you next time. Hmm catch you next time. Oh yeah.

I Think we have the Matrix A again I Think we're in the Matrix We? What? What did we just do? Well we press W instead of C and we list and look and yeah so he warm booted it and then we did list and thickens it because this doesn't necessarily Murray so it loses it. So and it just listed all rubbish. So there you go. But we do actually have our prompt but and let's see what happens if we run now.

Oh no, it can't even decode now stuff properly. We're gonna have to reboot that.