Hey got another teardown for you and you know we love vintage computers slash calculators. Here on the Eevblog got a Bobby Dazzler Look at this thing. it's the Canon Kanoa SX 100 straight out of the early 1970s I Don't know a huge amount about this is a bit hard to find information. Don't have a manual for it I do have a manual and a service manual for the later SX 300, which dates from 1975.

so I assume the SX 100 is the model like even one or two generations previous to that. but I did get a date of this of 1976. I'm not sure how accurate that date is because for example, the HP is famous HP 35 The first pocket calculator came out in 1972 and then 1974 had the HP 65 programmable pocket calculator. And this thing which weighs an absolute ton.

What is it? 10 kilos or something and is an absolute beast. Sure, it's got a printer and everything else, but this is actually a programmable calculator. not really a computer as such. I Believe it's only got like a few dozen memory registers and stuff like that, but it is fully programmable and you can execute programs and stuff on it.

So programmable calculator, thermal printer, everything else. So I Thought we'd check it out. This could make for an interesting teardown. Fantastic.

Still in pretty good Nick by the looks of it and got a full roll of paper to beauty. So if you used one of these things, let us know down in the comments or over on the Eevblog forum. Biggest Well, this is a quite an unusual beast for like the early 70s as I said those pocket calculators and I started coming around from 1972 onwards. So you've got to question the value of something like this in like 74.

V As I said the 1975 I believe is the date for the SX 300 which is basically it looks identical to this. It might have some extra performance or features or something like that, but it looks near identical to the SX 100 that we've got here. So yeah, this huge big desktop beast of thing which weighs a ton and you know I don't know how it would compare with the HP 65 for example from 1974, but that could fit your pocket. this lis have a hard time.

So was this thing just too late to the party? Did it miss the pocket revolution I don't know. when was a Canon this the first pocket calculator did they get into pocket calculators I think they did eventually. Um, but yeah, did this one miss the boat? I don't know. Anyway, let's tear it down see what makes this thing tick? So check it out.

It is actually pretty sexy looking. I mean you know the light I actually do like the keyboard layout, which is quite nice. You got your trig in scientific functions over here. You've got your regular keypad exponents up here change sign and I speak zero key I don't know what the start and presumably start program or whatever I've got some additional functions over here.

your parentheses. We're going to dedicate it in verse key. Fantastic. And then it looks like you've got some of the programming keys over here and then a whole bunch of interesting looking stuff at the top and some sort of recorder I don't know what that is.

we've got, you know, debug and programs and step backs insert delete programs, then we go to our degrees. radians, gradients, all that sort of stuff. and then we've got how it rounds I mean does it always round down? Does it always round up? or does it do the five-four thing? Fantastic. And then what looks like our fixed number of decimal points.

So F would be a floating point I'm going to assume and then no decimal points. one through two, six. Something like that Anyway, does have a rather interesting layout. my right, don't mind it at all.

I think it's pretty nice and on the back of this beast I've got a weird-ass mains connector. don't know what that one is. offhand. We've got to unfortunately have lost the backing plate on this thing and two things which there doesn't seem to be connectors on the back there.

so I'm not sure what they're actually for or maybe some sort of expansion thing, but there's no meeting internal connectors. my looks of it, then what looks like a 48 colander 24 column selector here for the paper, presumably. I've got a full roller paper in there and beauty. All the best stuffs made in Japan and this is the fancy pantsy non-interference model.

Anyway, let's crack this thing open. I'm going to assume that the feet aren't part of the thing and these screws around here will hold on the top part and the top part should just lift straight off. That would be very nice. We should get a good look at the innards.

All right, let's try and lift it of course. I Expect all this. you know, early 70s. who knows when they started designing is this thing? By the way, if you've got an accurate date when this thing was released, please let us know in the comments.

anyway. I'd Expect all like all Dip construction. it's probably will it use a and actual process or will it use discrete logic processor and stuff like that? I Don't know. It's big and heavy enough to sort of have enough chips - yeah, there's a few wiring harnesses.

Oh, they got a decent length on that. look at that. There you go. Yep, nut.

Looks like we've got some sort of process and that's certainly not. Certainly not all discreet, that's for sure. Oh, I've got some look at all the hand wiring. Oh, look at this.

So we've got some diode logic down there by the looks of it. and jeez, that's all. pretty how you doing, didn't it? That's terrible mural. but you know, not uncommon for the era though.

but you know they're sort of like cable-tied stuff. Lots of budges Wow look at this. Well, no this point. one-inch header and ribbon cable rubbish.

no cottage, and each one of them individually he'd shrunk and soldered I do like how they've formed the middle work up here to keep the connector in. That's rather nice so it can't fall out. That's pretty good, but it kind of all sort of fell apart up here when they went out. I Got that connector? Rubbish.

We can just hand solder those puppies on, thank you very much. I Check out these poor old trainees here over on one side, like falling over, staggering off to one side. No one took pride in now keeping those straight when they sold it to me, and that's for sure. But you've got a diode Bojan here and resistor sort of stand it up.

those diodes I don't know if they're a bodge or they're you know there's no. There's no traces on the top, so have they like drilled through the board and like added those diodes? Hmm. have we got a like a diode diode gate there or something? Anyway, this cap seam here seems to be budged on an HD 3541 I don't have to go google that one. even my Google foo is off or I can't find any info on that if I can I'll link it in.

but anyway, we've got HD 3541 which looks like some sort of processor, then the HD 35 42, then the HD 3543. So obviously these are SRAM's here 35 42 I'm not sure what that'd be doing. it's probably not a row I wouldn't be a mask ROM I don't I have to take the rest of it open. But anyway, we've obviously got some sort of Hitoshi chipset.

Okay, one of the oldest ones I can find is 39th week 74. so this is getting close to being, you know, a 1975 model. So as I said like it's you know how competitive was this in small bunches up there? Loved it. How can be ground strapped, going off somewhere, buggering off? - is that going off to the printer or whatever Oh flat flex ribbon.

fancy pantsy like yeah. how competitive was this thing in like 1975? Yeah, sure. It's got a printer and everything else and it's good. You know it's got some programmable functionality in it, mate.

You know a lot of people will prefer a desk model over a pocket one and stuff like that, but yeah, I don't I want to have some good advantages? So you know, maybe Furber You know, scientific engineering teams something like that who wanted a paper trail and stuff like that cuz that you know it's an often that's vital so that you can that? That's why accountants. A lot of accountants will still use the old you know, the paper tape thing as they add their you know if you're bringing bringing your shoebox worth of receipts and then they sit there and add them all up. Then they've got like a paper to track paper tape trail of you know, the actual stuff that they entered in so they can go back and check it so it would have been valuable from that point of view. But Jesus A general-purpose scientific you know, calculator on your desk? you wouldn't bother wasting your desk space.

So how quickly did something like this go obsolete? I Wonder so generally I'm quite surprised by this. This has like less stuff in it than I was expecting. It looks like a kind of reminds me of like a you know, a 1970s vintage. PC something like that, you know or in like an early 80s vintage.

PC Where like with the just you know like that looks like the process of the RAM and everything else a couple of you know, discreet jelly bean glue, logic and all the other stuff. but yeah, I was just like I don't know. expect like the big weight of it. Maybe I was hoping that there were, you know, lots of big cards in there with lots of like a discreet processor and you know, a ton of stuff and nope, looks like it's just a micro on something else.

Granted I haven't gotten all the way under there, but I don't think this card extends too far back under here. so all the weight comes from like the three layers of metal work it's got here. You know it's all big, thick, heavy stuff. So yeah, that's why it weighs a ton.

If we lift off the printer and storage mechanism, we get this board under here. It's all just, you know. seven, four series logic. Nothing.

nothing really much doing there. I Love the graffiti jumper wires look. joining these grads at Power? Yeah, there's no that's ground. It's gonna be joy joining the grounds like this.

like they couldn't get that on the board, but they couldn't get that on. The layout doesn't make sense anyway. I Believe that this is the based on where the wirings buggering off to. This is the controller for this mysterious tape drive storage mechanism thingy.

So this is like really interesting. It's not a tape drive and it's not a cartridge. a system. this is a head.

Okay, you can tell because it's got these Co axes going off here. So this is like a read/write head and it's like like it can't like there's no loop tape or anything like that to do it. So I think it's just like like a magnetic stripe card kind of thing, which wasn't that uncommon back in the day. HP Used some like magnetic swipe cards for storage I Mean it doesn't store a lot, it only needs to store like you know, hundred like and I don't know.

dozens are by. its maybe a few hundred bytes or something like that. so you can easily store it on like a strip. like a little credit card kind of thing.

and that's what it looks like it is. And yep, sure enough, you can see that down in there. look, there's a roll. Oh oh that.

I should have touched it that that roll is gone. it's gonna say yep, that almost looks like a cork. Kind of. that is weird.

Anyway, that was a roller. Whoops! And we've got a micro switch there that this one's actually actually a detection for the bottom. So we got two slots here. Focus, you bastard.

Alright, so these rollers down here push against the magnetic. head up here. it looks like this: like I don't know it so much. it's just disintegrating and sorry I'm not putting any force on that.

it was. So I didn't destroy it. it, it just had stood no chance of working at all. anyway.

so we've got the gear chain for all that to actually drive that shaft in there. that I said I'm not sure what's doing down the bottom though. I've got a microswitch. There doesn't seem to be a oh okay, no I know it happens.

Oh yes, it's obvious people are probably screaming at me. It's a paper thing. You put it in the top, it pulls it through and shoots it out the bottom or vice versa. Maybe it.

Yeah, by the way, that can't it can't go in here and come out here cuz it to get caught on that lever in there that make a switch lever. So obviously you have to shove it in the bottom here and it sucks it through. It gets caught on this plastic roller on there pulls it through and then over the head like that. Yeah, that's the way it goes.

So some sort of you know paper magnetic strip card storage program storage thing probably held. you know a hundred couple underbite stops thing of beauty is a joy. forever. Look at that that is beautiful.

Look at all those end on resistors with the white insulation over them. That's fantastic. Then we've got a bunch of Op amps there by the looks of it. and this is all the the head circuitry.

So this is all the head driver and the head receiver for the magnetic drive there. So yep, that's all in its own separate shield it can wear as all the bottom board down here is just all digital logic and there's not much some smarts in that at all. but that's gorgeous. I Love that.

and I Do believe. Take these two screws out here. this board is going to slide out from here. Yep, Yep, you're that.

Ah, someone was thinking whoa no and I was gonna say is that a delay line Look remarkably like a delay line But oh well. come out look well. this has seen better days. Look at that.

I'm not sure if you can see that it's sort of like yeah, you can see the shine on that. It's is that something almost looks like it's conformally coated, but not all Hawaii seems like stopped-up like it's really patchi's like stops here. It's just if it is conformal coating, look at patches in there. It's a worst I've ever seen or is it some sort of I don't think it's like any sort of fluid contamination or something like that I don't know.

Is it like just like they did didn't clean the board? It's got some old-school flux cleaner residue on there or something like that I don't know. and this layouts all hand taped to know that. CAD Rubbish. So as you can see it's just seven for logic and once again, another seven for LS or any sort of seven 4hc rubbish or anything HC wasn't invented then? um yeah.

just this good old seven four series logic. So yep and budges on there like I don't understand that ground. like why can't that look that's connected to there? Why can't like. did they actually leave it off here? like look, there's room for that trace to go around there and around to there.

Did they are named? Maybe not. Well, I couldn't Then dropped it. Yeah. could have come through there like that under that cap.

So like what or that? maybe they just had an issue with you know your via count something like that, you know they would just want to lower impedance. Anyway, you can see that there's not not that many bypass caps on there. they've got a little jump links MC whatever that means and a couple of you know, steering diodes and whatnot. But yeah, not too many bypass caps.

don't need any of that rubbish. I Love how the the silk screens under the chip that's really handy isn't it? And the backside here is mostly, you know, seven for logic and that sort of jazz it. Oh, it's another another slot there. don't know what plugs into that one because the other board bus plugs into the top here.

the the tape drive things. so card reader. Drive So there's another another socket down there which is interesting, but once again, oh yeah, what's this thing? I See 60 to 70. It's upside down so all the electrons are gonna fall out.

Is that you know there's a whole bunch of diodes there? Do they go into it? I'm not entirely no idea. Anyway, this is interesting. Look at these atashi chips here. We've got a Chin 35, 401, 402, 403, 404 and you expect to go 405.

but it doesn't. Here it goes. 405 is actually down here: 406 and then 409. So where's like 407? 408 Anyway, it's a blue bodge wires running everywhere and we've got a little.

Is that a little? Yeah, That's it. Yeah, a little transistor in there and they put a little that looks almost like conductive foam on the back of that what on earth little trimmer there. Don't know what? They don't know what they're doing there. but the the main crystal down here I don't know what? what frequencies that doesn't even have it written on there? Weird Yeah.

One thing you don't see here is your traditional EEPROM Well, you know, where's Willy Where's the rum? Obviously this thing's the processor. These are all the same part number. so this has got to be Ram but there's only fat. Like there's five of them.

so that's like an oddball number. This one here could be some sort of memory controller or something, but like I don't why you'd need it for SRAM I don't know. Anyway, and it looks like these are probably the roms 1 Cm, 2, 4, 6, 7. That doesn't make sense really.

and it's not that one because that's not a sequential number along with them. So those in sequential number order kind of makes sense from a like a Rama point of view. so they'd be like mask roms. All right.

Check this out. We actually have the service manual with full schematics for the SX 300 and the only real difference I can 5 26300 and the Sx 100. Maybe apart from you know, like a memory difference or something like that, Is that the SX 300 a magnetic tape system as opposed to the magnetic card system and that's about it. but everything else seems identical.

Check it out. We have a ton of stuff here and here's a block diagram. We've got the optional memory box they call it I Guess it's a memory card. There's the control chip, which is that main one that I thought was the processor.

It's not actually a processor as such. Because this is not a microprocessor based system, this is like a multi chip processor system which is different. So it's got a controller. So in effect, they're making up a microprocessor with multiple chips.

So we've got a control chip, a data chip, and an SR arithmetic chip here and there. Those three main chips that we saw and I'll point out in a minute. We've got six different roms and we'll go into the different roms. They're not all program roms and then we have a printer controller which has its own ROM It's got a character generator.

ROM We've got a display controller and gates and various other stuff. So there you go make card amplifier. well that sort of stuff. I Love the little wiring diagrams.

Here's the keyboard circuit so it's pretty basic matrix arrangement now. I Find this part really interesting. This is the auto clear and clear. You remember those two buttons on the top? They're actually like they're I Think they're wide outside the matrix and into this dedicated circuitry which literally like hard resets stuff within the processor.

So it's very serious business. It's not like the processor. it's not like the instructions in the process of read the matrix keyboard and oh, you've pressed the clear key and it just clears it in memory. It actually it resets the processor to a - like a knowing state and stuff like that.

They got diagrams and things like that which is really cool. Crystal Oscillator Three point Five seven megahertz whether or not it's slower in the SX 100 I don't know and he here's the HD 35 41 that's that control chip and once again here is that: HN 35 409 Those six roms seven was it down the side There this is ROM number five so these ones are the Twe and TD these are like two keyboard there you go so that'd be so. this is a keyboard mapping ROM So it doesn't actually contain processor instructions or anything like that. it's a like it's a mapping ROM They do some old-school mapping I'm gonna show you an old project I did I might I'll make a mental note I'll do a video showing you a an old school sort of like a state machine compiler that I wrote back in the day using roms to execute instructions and programs I might see if I can dig that one out of the archives.

Remind me pester me if I if I don't get around to it and then once again there's mention of the 35 42. that's the data chip so that was the one next to it and it looks like the 35 41. So what we thought was the processor but actually cuz the control chip. It actually handles the keyboard.

but it's not a keyboard controller. It actually is a part of the microprocessor system. multi chip processor system. A lot of stuff they got in here.

It's an amazing Wow Nobody does documentation like this anymore. It's great. So there various flags. You know processor flags and stuff like that so you know it's it's implementing all this stuff which you'd expect inside a microprocessor.

It's doing this with these dedicated or well, these are like separate chips joining them together to form micro processes. So there's the controller yet again. and it's got the memory box and interface. You see how that controller not only ties into the keyboard system, it ties into the memory box, memory and interface and the auto clear and instrument converter inst converter.

and ROM and all sorts of stuff and data transfer. So there's a separate that separate data chip. It's not actually A so it's just part of the processor. it's it's I Don't know, you know, processor internal, what actual architecture? This is how many bits it is, all that sort of stuff and what sort of architecture to be closest to is that? is it? Like emulating old you know, 80, 80 or 8 W 8 or something like that? I You know I don't know or is it at its own thing? Who knows.

And here's our ROM, the HM 35 for o 1 o 2, O 3 and Oh 4. So four of those roms are actually dedicated to the printer unit. so one is the character generator here and it looks like the others just like generate the the the data to control the printer and stuff like that. So once again, these aren't instruction based roms.

they're like hard-coded like almost. You know you could replicate these with PL DS and F PJs and you know it's stuff like that. So it's really using the ROM as a lookup table to generate. You know waveforms and insulate not instructions.

there's not the correct term. generate the required waveforms to drive the printer. Then you've got your other four roms here. Two of them are display roms.

one is a TW that was the keyboard wasn't at twe in timing type thing and this was another one and there. some of them opened. drain are they anyway? Whoa. What's a NAND gate? There's a display block diagram, cathode, driver, and once again, the these roms down here are controlling the actual segments going into the seventh, the multi channel seven segment displays.

So they're in effect. They're like data to seven segment decoder roms, so they're actually doing those in roms which is really quite. You know it's not a bad way to do it because mask roms. Not gonna say that was cheap, but they were.

You know, simple and effective back then. Fear for doing stuff like this so you didn't have to generate C In effect, they're using these mask roms as custom logic. Then we might have some sort of block diagram here There you go. mentally flip between those and you can see.

and there's the block diagram of the card driver in this case. So that'll be the read and write art, that'll be the tape controller and stuff like that. So this would be different on the SX 100 of course, because there's a card reader instead of a tape. Maybe it uses like the same system, except if physical tape, they can just store more.

Maybe that makes sense that they'd probably use the same protocol. so maybe all the you know a lot of the electronics of the same. maybe the tape and everything else. and it's just like motor drive and stuff like that that differs between the two.

And then we've got our power supply circuit. and there's our standard. You know there's our Darlington pass configuration like that. and we've got a Zener in there.

Two plus five, minus seven and a half plus 12 plus 9 Minus 12 minus six minus four. G's needs a lot Anyway, how cool is that? I Love the diagram of the capacitor and the leads going off. That's great. Nobody makes manuals like this and they give you the pin outs, little datasheet, pin outs and stuff.

Absolutely fantastic. Hats off some. I Went to a lot of to more maybe is one person put this manual together and then they've got the the foil. You know, like yeah.

I'm gonna follow that. look at that. it's very arty isn't it? That's terrific. Wow, that's great and then exploded views and that looks like a parts list.

That's that's incredible. And for all you power supply aficionados, there you go. Don't you love the the tubing? That's not even heat shrink good? I Think that's just tubing. We've got our capacitors mounted down to the chassis.

Quite old-school It's a bit how you're doing over here with the what is that? the you know, the series pass transistor for the linear regulator upped it. They got a heat shrink on there, but you know they're putting it down. they're using it as a heat sink and well, there's not much else on there. bunch of caps.

That's it. Big ass inductor? or is it they what on earth? No, it's a bridge rectifier. That's a big-ass bridge rectifier that Wow huh? I sees on the other side for leg bridge rectifier with the hole in the middle so you can like mount it on a chassis mount and an arrow telling you where to shove it. Nippon Chemi-con Fantastic.

You think this is still gonna work? Yeah, I think so. Oh gets a bit more interesting on the back. Check it out. There's a whole bunch of other pass transistors as well, with some little smaller trainees in front just to drive the base of those suckers.

So now they little Darlington configuration? perhaps? So I've fused up here I love our little connectors like that. Look at that now. Look at that soldering under the wires there. beautiful, wrapped around a thing of beauty.

Look at that. Fantastic. and our transformer over here made in Japan Well, a bit stuffs made in Japan that's certainly a hunk of iron contributes to the weight, obviously. And then I got our motherboard down in there, which is like please excuse the crew D of the shot here.

all sort of. you know, like a phenolic base type thing. It's not not exactly a first-class board that backplane there, but it doesn't have to do much. So there you have it.

There's an aerial view of our Canon programmable calculator. Isn't it fantastic? Early or in this case mid 70s, but this would have been designed in the very early 70s. I'm sure and it's just got mysterious Hitoshi processor in there. but coming in for landing on our camera there? No.

I don't have any of that stabilizer rubbish turned on Anyway, look at that. Oh, if you want to see everything's made in Japan There you go this your motor for all your motor fanboys and there's a closer look at the head. it's all gunked up. it's all potted, a couple of coax is coming off there, not much else doing.

Here's another look at the keyboard. got our diode steering of course, rail it'll be am a tree and then we got some physical switches up there. They got cutouts in the board for those. there's our rotary selector for our no decimal point indications, switch through our degrees, radians, gradients, and all that sort of stuff, and then our display up there and that, the wiring for that.

That's all. Pretty how you doing. Unbelievable. All right.

let's see if this thing works. Let's pair it up to 40 I've got some alligator clips on the back. She'll be right. no worries.

Mutual and Phase 240 Volts 50 Hertz Here we go. Oh hey, why not check it out? You can hardly see it. Geez, that's a tiny little 7 segment. LED display.

Look at that. but it looks like it works and we don't win a chicken dinner and check it out. It's still prints. Well, it's still paper.

paper, paper feed print Oh Check that out. Thirteen decimal places. That's pretty impressive. Well, yep.

I've got printer off thank you. so that's pretty impressive. We've got 16 digit mantissa three digit exponent Wow This thing was kicking some serious ass. All right, So let's clear that let's do the old up.

Whoa. Ginge. Okay, bit sticky. let's do the old 69 factorial, shall? We've got a dedicated factorial key? which is, you know it's a bit.

how are you doing? Oh I printed the damn. Oh, you see how it sequentially came up with that now? Printers going haywire? What? Oh, it's one sick puppy. Okay. I repaired it I Think it got past the out of the jam over to the end.

Stop there. so maybe it'll Maybe it'll do something now. So that's trial. Sixty Nine Factorial again.

Shall we? There we go. Hey, that's pretty quick. All right. So let's try the famous Calculator Forensics.

So what I'm gonna do is Nine Sine Cosine Tangent Arc Tangent Cosine Arc Sine. There we go. There's our calculator Forensics result for those playing along at home knots and not bang on. Nine Eight Point Nine Nine Nine Nine Nine Eight Six Double Four One Eight A Double zero and I'm sure that doesn't match in a well.

Had to be interesting. I'll look up the database of that and see if it matches, but of course that's not going to probably it. Who knows. It might use the same algorithm as you know, some other calculator chipset or something like that, but this one anyway.

Um, and that's full floating-point mode of course. What if we haven't actually tried this? What if we change that on the fly? not doesn't do anything, but if we did that on the fly, let's say we had six decimal places. Try it again. Nine Sine Cosine Tangent Arc Tangent Arc cosine, arc sine.

There we go and whoa, So that's supposed to be six. Okay, so that doesn't work All right. I Know you want to see me run a program, so let's do it. It's actually not too bad at all.

Um, Ope is operation mode so you know this is like one plus two equals There we go and it's going to print it out. One plus two. There we go. It actually prints it out.

But if you want to record a program, you put it in to learn mode like this. Okay, it will clear all like that. Now this is you can actually store multiple programs on here. So SP n n key Here it means store program in n So you've got to give it a hex number.

So we'll store program and it says unfinished here so we actually have to give it till at zero zero. Okay so we're now inside the so we're storing a program Now we can do our sequence. So if we go one plus two plus three equals printed all that stuff out and then we just go in program like this. Zero zero and we're good to go.

So it's stored our program now and we can go back to operation mode like this and we just press Start and it'll run our program. It just executed our program and gave us well. It gave us our answer here. Fantastic! So it's given that and it's displayed.

Oh, you can't see it. It's not very good. The printed: The print is not great, but it has actually printed out that and it was printing out our program as we were going because we had the you can turn the printer key off here if you don't want it to Y do that. but there you go.

That's pretty neat, huh? Let's try program print I haven't read the manual on that, but I see if we press that? Yeah, one plus two plus three. Plus there it is. That's our program that we entered in. Fantastic! And you can store multiple programs and you can like go into debug mode.

you can check mode which allows you to go in and edit and all that sort of jazz. and I assume load and record software shoved our card in there. we could record our program to magnetic card I Guess so that's pretty groovy, isn't it? I Actually like that? It's actually, you know it's fairly well thought out. It's fairly simplistic once you know I mean you can like obviously just walking up to it and trying to use it.

But once you, you know, spend just a few minutes reading the manual and you go. Yeah, that's you. know that's pretty obvious. Of course you can go in there.

You know, if you want to edit your thinking, go to particular lines and do edits and inserts. and you know all sorts of stuff. So you can modify your program and of course you can do Y go to S, go to various steps. Looks like you can set you know, flags and things like that, column prints and line feeds.

It's obviously fix. you know, does that fix the number of your decimal places or whatever? But anyway, you can do various. you know, programmatic functions like that, so that's it's not too jazzy. I I'm kinda liking this thing.

It's really good and it works. What? Street Still trying to figure out why. if you go clear all and then see it gives a couple of ones, a one there and a something over here. Yeah, I don't know, not sure.

Anyway, that's a fascinating example of 1970s calculator technology. Hands up if you used one of these or an older model or something like that. But anyway, I hope you found that interesting. If you did, give it a big thumbs up.

and as always you can discuss down below. Catch you next time.