Inside the Casio CFX-9850G Graphing Calculator

Graphing functions... IN COLOR? Yes! It's now possible in the brave new year of 1996. Join me as I try to get this thing working.

[@legoman8960]

It’s 01:08 AM I should be sleeping, but this is more important right now

[@scottcol23]

way more important than sleep. I see we have our priorities straight

[@Vapor_Roads]

Indubitably, a grandiose amount of importance over sleep.

[@ThePlanet_L.I.]

😆

[@jonasgustavsson7496]

🤣

[@mikebell2112]

I think the switch changes to the coin cell so that you can change the batteries without losing what's in the RAM.

[@howard81]

I’ve had the mono version of this calculator on my desk ever since high school... must be 25 years now! Casio was king here in the UK, nobody had TI.

[@d3v1lsummoner]

The proliferation of TI calculators, especially graphing sorts, is purportedly due to their lobbying with education councils and US State governments. You are often required to have a graphing calculator and often that calculator is a TI. If you have a Casio, be prepared for your teacher not to teach you how to use it.

[@Afrotechmods]

I had this. It was amazing. Apart from the lack of symbolic algebraic manipulation I still think it was better than the TI-89. Also 20:20 for Bud's appearance.

[@spakecdk]

Usage and feature wise, i think TI calculator were almost always inferior of the "big three" (TI, HP, Casio). The only reason they were popular in the US is lobbying

[@ShahZahid]

dude im really surprised and happy to see u, hope ya doing well

@@spakecdk Connection cable and games to copy around. That's what sold it in late 90's Finland, at a time when mobile phones had snake and not really anything else 😄.

[@sdttnkara]

Where have you been mate? I hope you doing good.

[@howard81]

Later models did have that, and a fancy backlit screen too! The one in the video would be mid 90s, as I had the B&W version for my GCSEs. It’s been a staple of my desk ever since 😁

[@Shadowcat]

This "32K" thing is not bragging. It's part of the Casio design language. All of their hardware does have most notable features printed on a case. Wristwatches tell you how many alarms they have, if they have a solar cell or shock and water protection built in. Keyboards tell how many sounds they can play and how many rhythms they have. Calculators tell how much memory they have and what are their functions (like graph drawing and such). It wasn't there to impress anybody. It was there to just straight up tell you what you get and I love that part of Casio design.

[@DavidWilson-vo5rl]

I have this - bought it for college when I was 16. 24 years later and it still works and I still use it.

[@bahathir_]

It reminds me my Casio fx-7000G, which I bought in 1986.. . Then I bought Casio fx-9700G in 1992. I modded both calculators to use external 9V battery, which very economical. The LCD is the SHARP's LCD. Thank you.

[@instahawk8422]

Gas station stories from america are always fun to listen too because in the uk we don’t have them everywhere mostly in the uk we have them next to supermarkets they just sell basic grab and go stuff you can’t do a full shop while filling your car

[@TheRealSmithFamily]

We have those as well in the U.S., but more and more of them are becoming more of a grocery store for those that don’t want to go to a supermarket. It’s annoying when people fill their car and then go inside to shop leaving their car parked at the pump.

[@1pcfred]

We have a gas station here with a sports bar in it. Among other things.

[@ForOurGood]

Ben Heck. Destroyer of calculators.

[@8bvg300]

Yay! I was waiting to see if you'd get to this calculator. I had one back in the late 90's and still have it today!

[@roasthunter]

Your video inspired me to finally fix my childhood calculator, had it for over 30 years, Casio fx-250c. Membrane had worn away on he battery compartment, a bit of silver paint and working again.

[@ShowMeInHD]

Used this in university days late 90s, still have it.

That *was* cool on -96! I got mine that year and I was sooooo proud :D

[@ConveyorMan]

Best video ever about the calculator.

[@me0262]

Excellent! I had this same calculator in high school and college. Couldn't really get any TI programs for it, but a program to factor polynomials was used very frequently by me.

[@danielcohello2471]

Your video series tearing down calculators is simply so fun to watch! Since a lot of them have 2 PCBs I would really love to watch a video where you turn a graphing calculator into a more portable one, just like the CASIO 9860g Slim is a clamshell version of the 9860g, I wonder if that is even possible with other calculators. Anyways... great video!

[@charliemopps4926]

Wait... Verona road? Do you live in madison wisconsin? That goodwill is 3 blocks from my house.

[@xyz2112zyx]

You made my entire year with this! I loved this calculator back then in the '90s, but I never had the opportunity to get one of these. Thanks, Mr. Heck! (It sounds like young Spiderman saying to Iron Man: "Thanks, Mr. Stark"... hahaha...)

[@malelonewolf80]

Had to watch this since I still have this calculator that I got about 20 years ago. And it still works as it should.

[@mina47879]

Very late, but the "lag" in the colour is due to how the display works. It's not actually a colour display, well it is, but not in the sense you typically think of. Its kinda actually a grayscale LCD. It uses some kind of filter magic to produce the colour based on the "brightness" of each pixel (probably the angle the crystals are twisted to i guess). Hence it briefly shows other colours due to the slow response time if the lcd pixels turning on and off.

[@chrisbailey7384]

In a nutshell, the magic filter beneath the front polarizer works as a birefringence.

[@samsoulee]

I love those "old" calculators !! I really felt like having a computer in my pocket back in the days !

[@dennisd7]

I had this one back in the day - I programmed it to show the Mandelbrot set in colors, good times.

[@llib32]

Hi have this exact calculator sitting in my desk at work! Found it a few years ago at a yard sale for $2. It's a pretty cool little calculator.

[@FredPilarczyk]

What amazed when I went to Buc-ees (once) was how many options of grills and smokers they had. It was more than Wal-Mart, or any store I had ever seen. The place is legendary for sure.

[@n.h.s.a.d.m.]

Cleaned up very nicely.

[@WDCallahan]

That switch lets the main batteries power the memory while you switch out the backup battery.

[@ray73864]

What's interesting is that the CFX-9850G plus (Which I have) doesn't have that switch at all.

[@WDCallahan]

@@ray73864 I went and looked at mine and it doesn't have it either. But I remember that feature from an earlier model.

[@mc_cpu]

I've never seen a colour calculator before! And Bud "helping" was adorable.

[@PixelMaker04]

That's what they don't tell you. Blue is the new black. I've got a CFX-9850GB PLUS and its older, much chunkier brother CFX-9800G in my slowly growing calc collection. Seems like it's a false black due to how the LCD handles the colors. I did a test on the graph using all the colors with the same function and it goes as follows... Orange - primary color Blue - secondary color Green - tertiary color I was testing to see if they would overlap, but they overrode the previous color instead. So it seems as it goes from orange to get to blue it just looks black. At least that's what I see.

[@vegisaynom]

One of these got me through my exams here in the UK! My dad bought it before I was born and it's still good! (I was born in 97) Have 2 single colour versions now too :)

[@KB1UIF]

I have a Casio CFX-9850GB PLUS-L and right on the front of these calculators including yours they state 32K !! There are only the 3 colors, but you can change the contrast of each color to effect the display. The color difference is all down to how you set the contrast for each color. Like most programmable calculators or organizers you backup the programs and stored data with a CR2032, when it comes to changing the batteries you can switch to either battery type to keep the memory contents intact. To change the Main batteries you make sure you are switched to Backup, to change the backup battery you switch to Main batteries. For normal operation you have the backup battery switched in. You can run these from an external power supply and the power jack is also a computer interface providing you have the correct cable. I know nobody ever RTFM but its worth a quick look for basic info. The manual I have is about 3/4" thick. I bought my calculator brand new from good old Radio Shack years ago, when I found it, it was reduced, the original price tag still there was $99.99 the reduced price tag $19.99. The color display can be a little tricky to see depending on your lighting conditions, but it is Color as opposed to the TI-83 calculators of the day being just Black and Clear. The Casio boots up into the User Menu as opposed to Just Cal mode and requiring extra button presses to get into the User menu as on the TI-83 Calc's. They are a little slow to draw the graphs, but I actually find that nice to watch. Enjoy !

[@enquiryplay]

I had this back in the day, except it was the more exclusive 64KB version. Everybody in math class was envious, or at least that's what I told myself.

[@gortnewton4765]

There's nothing complex about the fault. Power not getting to the main board, that's what it is. For cleaning contacts, get one of those little sticks from ice-creams and stick some 600 grit sandpaper on it with double sided tape. Works nice.

[@tookitogo]

For cleaning corroded contacts, tarnished PCBs and wires, etc, I use both fiberglass brushes and the erasers in pencil form (as in, it’s a stick of eraser encased in wood, so you sharpen it) of the type designed for erasing ink, so it’s basically a rubber-pumice abrasive. Works _magnificently._

[@johnpekkala6941]

I used one of these in school but the 64 kb version 9950G. I still have it and it works. I just now went and tested if there was power in the batteries still after being untouched for at least some years now and they are still all good with plenty of power! (No dim screen or battery alarm whatsoever) wich is amazing since u need a small amount of power to keep the data stored in memory alive as this was at a time way before flash memory became common. I guessed beforee it must be SRAM if requiring so little power that there is still lot of juice in the batteries after all years and all programs I wrote are still in there and working. Impressive! That switch BTW is if I remember correct there as an interlock to prevent you from corrupting/erasing the data in memory by accidentally turning the power on with only the backup battery while replacing the other batteries. The backup cell is just for keeping the RAM energized and is not able to power the rest of the calculator and thus turning power on without the main batteries in place could lead to undervoltage and loss of data. There is also no black color despite the 4 color icon above the screen but only blue, green and orange and blue is used instead of black.

[@emukidid]

I had one of these, I remember programming it over the aux looking cable port

[@TheRealSmithFamily]

People from the South or areas where basements are rare are always amazed how much less expensive their like sized houses are over houses in the Midwest. Basements cost a lot of money to dig and pour. Egress window is what you were looking for Ben! To be a bedroom it has to have a closet too.

[@ddummer]

Watched all the way and liked... there you go Bud.. the food is in the bag. ;)

[@kaysb80]

This was the calculator that got me trough the last few years at school. Not a great device, but OK for calculating ;D Anyway, we where allowed to use this thing on tests, but the teacher would go around the class room and erase all the devices before the test. So, what did I do? I opened it up, and disabled the reset button. I programmed a screen that would look almost identical to the "delete all memory" screen, and make sure the program was running before the teacher tried to erase it. The program reacted to the same buttons, and showed the expected text. It worked like a sharm, but sadly, I was too afraid of getting caught, so ended up restoring the reset button after the first test...

[@Pehr81]

I have this exact one at work! I still use it, it's much better than the computer calculator. Bought it back in 1997 for school. It has 3 colour screen which is suoer cool. We used to program these with lots of games also B)

[@preferredimage]

27:00 Definite Vic-20 vibe from that cyan border and white background....

[@dauerwerbesendung7045]

Curiously my calculator does not have this switch in the battery compartment. Everybody at school had to buy *this* specific model. I learned how to program some type of BASIC on this thing while being bored in french classes. Then we exchanged games and cheat-sheets with the link cable in class. Good fun. I always envied the faster TI Calculators, this thing is horribly slow running anything with graphics. The BASIC implementation must be quite shotty.

[@radda2179]

Oh man, I learned how programming works with one of these. I built my own blackjack game, a ton of apps to solve math problems so I didn't have to, and even made a fake memory clear screen so when the teacher forced us to wipe the memory before a test I'd still have my quick solve programs. Too bad I didn't go on to study programming later and went with something far more useless. Oh well.

[@pacman10182]

if you put the amount of effort into studying that you do into cheating, you wouldn't need to cheat but where's the fun in that?

[@kuremaClaimer]

I read the Wikipedia. That 'Color' thing is actually a contrast. That's why you don't have black. I wondered how they achieved the color in one pixel (with no subpixel), but now I know.

[@BenHeckHacks]

Ah that would explain why it has to cycle through the colors to land on one.

[@limaofarofa]

Some of those antiquated beasts can run music trackers and I think the ones with external connectors could interface with other gear, like Pocket Operators or something...

[@f1ggyc]

Surprising how little the interface has changed between this calculator from the 90's and the fx-CG50 calculator that I use in school today

[@Kelvari7882]

The way I see it, it's a fair sight better than the menu-driven interface of the TI's that I've used. Why change a good thing?

[@fermio100]

The beef jerky pun got you a like. LOL

[@GilliamVespa]

i still have that calculator for 25 years! i made programs for Pythagorean theorem and quadratic formula. that switch is to change power to the backup coin cell while changing the main batteries.

[@nexpro6985]

I'd give this a thumbs up but Ben keeps doing the crazy singing thing.😁

[@tigheklory]

When I was in college (1993) I couldn't afford the TI, so I got the Casio fx-7700GB and it got me all the way through college. I guess that says something? I did make some programs on it too. Games mostly.

[@Lion_McLionhead]

Even the monochrome Casio displays couldn't do black, only blue. It seems to do transient black when text flickers. You could make it do black by writing a program that blinked the text or try to add more colors by oscillating between the 3 colors.

[@McTroyd]

I had this calculator through middle and part of high school. At first I was annoyed that my parents cheap'd out and didn't buy TI. As I used it, though, I became quite fond of it. Then some jerk stole it, by which time Casio stopped making them, so I ended up with a TI-83 Plus. Man, the TI interface is horrendous after being spoiled by that well-organized Casio, though it did incidentally seem more powerful (and had more usable memory). I still use an '83 Silver that I bought when I started Community College. Wife has/uses my original '83+. 👍

[@aSpyIntheHaus]

I have this. Now. On my desk, that I use, not everyday but often enough. I have had it apart many times. I tried years ago to put white LEDs around the screen on the inside when white LEDs first came out.... They didn't fit

[@ray73864]

I have the CFX-9850G plus :) Had it since new in 1998 when I was in year 11 (Western Australian highschool).

[@agenttassadar7272]

Found my TI-83 silver edition while cleaning my mom's garage. Battery acid killed it. I was so bummed out. Found a working TI- 83 at a thrift store for 10 bucks a week later. God works in mysterious ways.

[@BlowTheCart]

Hey Ben. If you want Bioshock in space, play Prey (from Arkane in 2017, not the Human Head Studios 2006 game). Its basically a modern System Shock, and one of the best immersive sims.

[@davidmcgill1000]

Which even does the moon in DLC.

[@adam_sporka]

A friend of mine had one of these when we went to school. I remember there were only these three colors (+ blank), but no black. It would make sense - each pixel would be exactly only 2 bits. BTW, you could do a some sort of "hue rotation" by adjusting the contrast. If I remember correctly, you could make the orange almost invisible, green shifted to orange, and blue shifted to green. Or you could go the other way and squish two colors into dark blue. In poor light conditions and under weird angles the colors were kinda dancing around anyway.

[@ProbeGT2]

What's surprised me the most about the 8 bit guy's studio, is the price he paid to build this thing. The 1st estimate was over 100k$!!!!!! I miss his content tho, i hope the repairs on his house are going well.

[@theIpatix]

I had a similar version of this calculator and I don't think it has black at all, I think it only has blue, green, orange and white (and I find 4 colors more likely than 5 colors if you'd have a separate black). But yeah, the colors are really dull and the downgrade to a calculator with only back and white wasn't actually that bad since the later screens had better contrast. Btw, the "exit" button is what you use on these casio calculators to get back whatever was the previous menu.

[@feeterican]

Bucky's is like a gas station with a grocery store were here in Ohio we have grocery store with a gas station, in the parking lot, called Giant Eagle/Get Go. You get points towards your gas or vise versa.

[@DevilsHandyman]

I was at a Bucee's not too long ago and they told me they were going to make the one in Luling Texas larger. It is currently around 75K SQFT and they are basically going to double the size. Maybe more beef jerky varieties.

[@mjaerkens]

Hey Ben, could you do a catch up video with Felix? I was missing him in the last one you did.

[@osirismnunez]

Good point re: BTTF but I still don’t think it should be remade.

[@KillerSpud]

I used one of those through high school. Still have it somewhere, but it wouldn't do simultaneous equations with complex numbers for my AC/DC class.

[@madschquaka]

Thank You for that Bioshock comment. I thought I was the only one who noticed that they simply gave im developing the gameplay after that grappling hook feature.

[@BenHeckHacks]

Infinite's demos were just as mis-representative as Aliens: Colonial Marines but for some reason (great art direction?) it was given a pass.

[@MikeStavola]

Oh. I had one of these. I replaced it with a touchscreen model from Sharp. The touchscreen was completely unnecessary, and I preferred the color screen.

[@nigmaxus]

We are not worried about Ben talking to Bud, more worried that he is talking to his calculator's.

[@braedan51]

Remake Back to the Future? BLASPHEMER! *Points and screams in Sutherland*

[@RichardDzien]

I have the 9700 version. I think you might be missing a piece from the battery compartment. Mine has a piece of metal that latches into place with the switch that's there. I think it's there to remind you to make sure the backup battery is good before changing the main batteries. As it has no user writable ROM all the data will be lost etc etc.

[@falkkyburz]

Could the switch be to power the backup circuit from the main batteries if you have to change the backup battery?

[@scottcol23]

Welp... It looks like I'm going to be up a little bit longer lol. Can't miss a goodwill calc video.

[@hugosimoes5119]

I recently got a Ti-83 without some keys working and a CASIO CFX-9850GC PLUS with no keys functioning. Just needed to repair some traces for the TI-83. For CASIO... no protection for corrosion... there was a layer of battery leak. I had to scrub with some sandpaper and it was fine after and then I sealed the sanded traces with nail polish. Stupid way Casio didnt add a protection between the pcb and 4x AAA batteries.

[@CoyoteBoyUK]

High value calculator, expected to be owned by people who use it regularly, not ones who forget about it in a drawer for years, and the battery compartment is segregated from the PCB so if it's stored the correct way up it's fine. Bit of conformal coat isn't expensive though, so it's a shame.

[@hugosimoes5119]

@@CoyoteBoyUK What it costed back then, TI should have make them more durable. Like 2 wires coming out from a sealed 4x AAA and 2 more wires coin cell. Soldered ribbons between the LCD pcb and the logic pcb. etc

[@CoyoteBoyUK]

@@hugosimoes5119 why? Mine has lasted 25 years kicked around in a bag and left for a decade with flat batteries. Seems pretty durable to me. That's like complaining a car should be more durable so that when you crash it you don't have to replace bits.

[@HazardOfExistance]

Would you kindly make another video with Bud.

[@johnvictor9071]

I like the idea of the Back to the Future remake where, not only doesn’t the present day teenager know how to contact someone without a cell phone, but when they do figure it out, they have to remember the phone number.

[@comedyflu]

I also agree with you about a BTTF remake. But, I hope that they'd keep it faithful to the OG

[@synaesthesia2010]

it's never going to happen, the two Bobs own the rights to prevent it from happening

[@papamaanbeerVideo]

the screw on the battery is, so people wouldnt steal your betterys

[@bigblumerstrikesback]

I love Kwik Trip. Where else can you get an egg roll, fancy coffee from a fancy coffee machine that is actually pretty good (especially for the price), and hear Neuton Dance by The Pointer Sisters at 4:30am?

[@eformance]

It goes to backup power when the battery cover is removed, when installed it switches to main power.

[@rlSoldierB]

^ this

[@jastervoid]

Ben - any more info on how they implement that wacky 3 color lcd? Surprised they can’t do dithering with pwm for more colors but I guess the ‘video’ processing couldn’t handle higher bit depth, not without more video ram for sure.

[@BenHeckHacks]

While editing I noticed it seemed to cycle through the colors to achieve them. Like every pixel has to start at red, then green blue then black. Do frame by stop (stop video and then , and .) when it's drawing the curves.

[@chartle1]

I feel the same about the movie "A Christmas Story ". It was 30 years before my time in fact Ralphie would have been the same age as my mother. But Christmas in 1940 was not much different than 1970. We still used lights, not the miniature aka twinkle lights we still have today, that if one burned out they all burned out. We pretty much dressed the same, you would never wear t-shirts and jeans to school.About the only things that were different were the toys.

[@peddersoldchap]

Did the calculator close correctly after the tabs were broken? Thank you for the video, also!

[@brianm6337]

What acrobatics would be involved in shoving a Pico in as a calculator brain?

[@WDCallahan]

This is my calculator! I never got in to the TI stuff.

[@ToumalRakesh]

I had the same one. I even added a LED backlight to it. It sucked for programming though, the Sharp PC-E500 was way better for that.

[@Hiraghm]

They have basements up north and not down south because up north you have to dig 4 ft or more down to get below the frostline anyway... might as well make it a basement.

[@DAVIDGREGORYKERR]

HCD62121 HITACHI Processor (Zilog Z180.), R27V802D ROM, BS62LV1024-70 DRAM.

[@lelandclayton5462]

There is a Buc-ees here in Saint Augustine Florida. I went there and was like "Yep, a bunch of crap I would never buy" then left.

[@hansdietrich83]

3:50 that's how meeting my friends in 2010 worked... Kids having cellphones still wasn't a thing until then

[@mactep1]

Depends on where you live, i am pretty sure my brother already had some sort of Nokia or flip phone back in 2006.

[@olik136]

We had cellphones since about 2000- when the nokia 3210 came out- but we still did the normal landline routine because a single SMS was 0,40€ (about 0,50$) it was not uncommon for kids to have their phones taken away because they messaged away a few hundred sometimes even thousand bucks... my fathers working phone did cost about 2000€ every month..

[@greggsymington]

Ben, I would consider Charlize Theron's role in "The Old Guard" as both a Mom and a Witch...

[@jstro-hobbytech]

I have an identical cat that I call a purr engine hahaha

[@DesertJorden]

Buccees is amazing!!! Brisket taco baby!!!

[@LadyNicola]

I can't sleep until I hear the Lord of the Rings/Disney thing. 😂😂🙌😂

[@Pehr81]

The switch in the battery compartment is so you cannot power it on unless the battery lid is on.

[@thewolfin]

heaven forbid!

[@Pehr81]

@@thewolfin indeed XD

[@JustinFrost302]

@Ben would you do a Original XBox Laptop

[@frankstrasser6108]

Loved the bioshock series I agree one was the best I even did all the side quests add ons. I HOPE they make a new one then ide have to get a new series bioshock is my fav “new” series. There was a part on 2? Or one of the expansion where you go into a display thing and something said look behind you and a bunny head enemy was there scared the crap out of me lol

[@jkrigelman]

Looks like when Ben bumps the overhead camera it looses the signal for a second.

[@BadKarma714]

Do you think the little round battery had to be in there as well as the other batteries?

[@bonnome2]

The little battery is a save battery, for saving the settings and other data. Just like with SNES and gameboy cartridges.

[@Shl0kk]

Charlize was in Snow White... AS A WITCH. You stand corrected, Ben :)

[@lariveePhoto]

I always wondered how they dont get all the bond wires to move when they apply the "goop" on bare dies....

[@tookitogo]

My assumption is that it must be a fairly thin liquid before it cures. If it were thick, yeah, it’d damage the bond wires, but it would also look very different.

[@HazardOfExistance]

She was a mom in Hancock. Just don’t call her crazy.

[@djGLCKR]

Here's the thing. Bioshock's story and setting made it so you're always distracted while dealing with the three elephants in the room - Atlas' true identity, your link with Andrew, and the "would you kindly" click. In my case at least, you can be dang sure I got bamboozled the moment I made it to Andrew Ryan's room, and the room prior. Can't really say much about 2's story since I never bothered to complete it, or Minerva's Den. The mandatory Big Sister fights, especially while playing at the hardest difficulty AND with no Vita-Chambers made it extremely tedious. Infinite's issue is "We have a story, but there's so much crap and reality-twisting that we don't know our own story", plus the weak weapon gameplay and a handful of "Aha!" moments (like the hidden cache quests) that don't really help the case. Most Vigors were kinda okay, tho.

[@thomashamilton2240]

I had this calculator when everyone else had TI-83+. I cheated so bad with it since no teachers knew how to reset it before tests. Just wrote a fake reset program and kept all my notes! Good times. Incidentally, it was probably easier to just memorize the formulas than to learn to program this thing...