Background

On October 2023, Casio announced the successor of Graph 90+E: Graph Math+ (alongside Graph Light) at APMEP 2023 and went on sale starting from April 2024.

At some point in November, I discovered the limited offer of Math+ at Amazon.de (link) which was listed for 45 € and had me tempting to buy it, but did not do so as the removal of add-in support was the dealbreaker for me. Until February 7, when the Amazon.de offer was available again and the beta release of MPM was approaching, I ordered it and paid HK$ 500 (shipping fee included). It is cheaper than the current US-imported fx-CG50 sold at Taobao (CNY¥ 660/87 €).

At a glance

Box and content


Front and back


Case


First impression

The package arrived 10 days later. It comes with the new calculator, quick start guide, warranty paper and 4 batteries.

My first impression of this calculator: This looks like a mix of fx-CG20 and Graph 90+E! Immediately, you can see Casio goes for a clip-on design for the protective case like fx-CG10/20, instead of the slide case used for fx-CG50/Graph 90+E. The exterior texture of the clip-on case appears grainier than the predecessor as well.

Like Graph 90+E, Math+ adopts a mostly white color scheme for its body, except for the upper part which is black around the screen. Speaking of the screen, it is covered by an acrylic panel, which is absent from the previous generation but is used in fx-CG10/20.



The buttons are a bit harder to press than fx-CG50. To be fair, I prefer fx-CG50 buttons, but Math+ are infinitely better than fx-CG20 here because the latter buttons are either too small or too large, as well as lacking feedback especially on F-keys and numpad.

From the side view, the arithmetic operators are marked on all 4 sides of Math+, resembling its name and position as a Math tool.



And here it is: Finally Casio is willing to switch the USB port to Type C, after it has become mainstream for years. However, for some reason it is quite picky at USB-C cables because I only find 2 of them working with my Math+.

UI philosophy


The evolution of Casio fx-CG main menu.

Casio goes for the minimalist design and color scheme for the main menu icons. The new font also appears to be more sans-serif like when comparing to the previous generations.

Due to the removal of the function keys, tabs are used to handle multiple UIs and there are keys specialized for switching between them. This allows a full text display instead of the dense or abbreviated one seen in F-keys.

For some applications like Equation and Probability apps, Casio are keen to exercise the principle of input and output, by showing tabs in arrow shapes to clearly indicate the procedures to the results.

Functionality

Here I will pick some features that I have used frequently over the past few years.

Calculate (previously RUN•MAT)

Graph Math+ finally can let users copy the previously calculated results and paste it to the input field, a convenient feature that is present on fx-9750GIII from the beginning but not on fx-CG50 even with the latest firmware. This is one of my biggest gripes when using fx-CG50 for Physics and Mathematics courses, and honestly it is unfortunate that this feature is only available on the new machine.


Graph Math+ has the same trigonometric precision (8.99999999759468) as its predecessors.

There are 3 modes for exponential inputs which is recently added in the latest OS firmware (2.00). The first one literally inputs [X][1][0][^] at once, while the second mode is the one used in fx-CG50/Graph 90+E. The third mode is the compact style of the first one. Among them, the old one is better than the others because it does not require a number next to itself and can be used independently.




Syntax ERROR if using the third variant of exponential input alone.

The catalog on the other hand has some major regressions. While it is now an independent button, it can no longer display QR code that links to the usage of the function. When searching for all entries, I can only enter the first letter and scroll continuously until I find my desired function. The page keys save some time but still it requires more key steps than before.



Besides, the assignment symbol is moved to the shift menu. I am glad Casio decided to put it in the graph variable button so that I can immediately type x to save the value. Though it could be better if ALPHA mode is automatically toggled after entering the arrow. Given that entering List and Mat by SHIFT+1/2 is removed, this leaves the alpha variables the only data that can be assigned to in one or two keys. They could also bring the STO function from fx-92+ SC (and their other series of scientific calculators), where pressing SHIFT+RCL+Alpha (without EXE) after entering expression stores its result to the selected alpha variable.

Python

Right off the bat, when entering the Python app, you can see we are straight to the editor of a Python file named module.py. This change is remarkable and user-friendly, especially for students who are not tech-savvy. Typically, most of them will type a few lines of code for testing, and the file will be discarded afterwards, rendering the time spent on boring processes like creating and naming a new file useless at all.

Moreover, the font size is a lot more appropriate than the one in fx-CG50. I mean seriously, Casio did not make good use of the high-resolution screen on their Prizm calculators even since they debuted in 2011. The Python editor on fx-CG50 nowadays still uses the same 7 rows * 21 columns text display. Such font does not work well with programs having a lot of long statements and indents. And now in Graph Math+, the display is expanded to 9 rows * 35 columns which is a lot more pleasant. On top of that, thanks to the smaller font, line numbers are also indicated.



On the program side, Casio Python received one of its biggest functional improvements by porting Getkey from Casio Basic. The getkey() value distribution is also more intuitive than the old one. Without looking at the manual, you can quickly deduce the VARIABLE key has a value of 33 because it is located at row 3 and column 3. In fx-CG50, the equivalent VARS key holds a value of 58, while being at row 2 and column 3.

Casio Basic

After almost 30 years of history, Casio Basic has finally come to the end. This is unfortunate as Casio Basic is a unique programming language that motivated me to join the calculator community in the first place. While the improvements on Casio Python are great, the language itself just feels a bit too generic to me. Honestly, I had more fun programming with Casio Basic as the feeling of achieving something significant in my programs with limited environment is undeniably the best. Furthermore, I really enjoy using C.Basic as with BASIC style extended commands, it can achieve things that the current Casio Python can do as well (or even better than Python!), while keeping almost everything familiar to Casio Basic.

Link

The Link app no longer exists in Graph Math+, neither. Instead, whenever the USB is inserted, the calculator always redirects to System Manager and open the Connection Mode pop-up there. This change is rather troublesome because if I dismiss this pop-up, I have to reinsert the USB to let it reappear, whereas in fx-CG50 I can simply enter LINK app and press F2 (RECV) for USB connection, while keeping the cable connected.

Currently there are 2 connection modes for Math+: USB Flash and OS Update. The Screen Receiver option is no longer available here, which is disappointing because this indicates that Screen Receiver currently does not support Graph Math+… right? Well, it is still possible to screenstream this calculator, but it is hidden in the test menu, in which I will write more about it later.

On PC, the new calculator is identified as a USB mass storage with a capacity of 4.5 MB, a heavy downgrade from the original 16 MB. Not only that, I also tried to connect my Math+ to my Android phone, only to be informed that the calculator storage is not supported. This is yet another big regression because fx-CG50 (and even fx-CG10/20!) can be accessed by Android device and I can no longer use my phone to send files to my Math+ without using a computer.

Built-in apps speed tests

All calculators are at their default speed preset.

Calculate - Σ(x, x, 1, 100000)
fx-CG20CN (OS 2.02): 102s
fx-CG50 (OS 3.80): 55s
Graph Math+ (OS 1.00, from Lephe): 58s
Graph Math+ (OS 2.00): 62s

Calculate - ∫((x^3*cos(x/2)+x/2)√(4-x^2),-2,2) (Courtesy to Krtyski)
fx-CG20CN (OS 2.02): 15s
fx-CG50 (OS 3.80): 8.5s
Graph Math+ (OS 1.00, from Lephe): 9.0s
Graph Math+ (OS 2.00): 9.0s

Python - 1000 N-Queen loops (Courtesy to Xerxes)
fx-CG50 (OS 3.80): 0.119s
Graph Math+ (OS 2.00): 0.120s

Python - Factorize 96835724136209 (Courtesy to Krtyski)

fx-CG50 (OS 3.80): 107s
Graph Math+ (OS 1.00, from Krtyski): 110s
Graph Math+ (OS 2.00): 114s

Python - Calculate π using the Monte Carlo method (Courtesy to Krtyski)

fx-CG50 (OS 3.80): 151s
Graph Math+ (OS 1.00, from Krtyski): 149s
Graph Math+ (OS 2.00): 148s

Here, I can confirm that Graph Math+ has almost the same performance as fx-CG50, although it seems to me there is a slight performance dip between OS 1.00 and 2.00 of Math+.

Interestingly for Python, Graph Math+ have a generally faster graph drawing speed and slower pure computation speed when comparing to fx-CG50.

Test menus

The diagnostic test is still present in Graph Math+. To enter it, turn off the calculator and hold [HOME][x10^][AC]+[ON]. When the diagnostic test pop-up appears, press [SETTINGS] and [9] to enter CY875 test menu.



The new addition here is the OSUPDATE option which does exactly what it is for.

Like Graph 35+E II and Graph 90+E, Graph Math+ has an exam LED on the front side to comply with Baccalauréat. As such, the Math+ diagnostic menu contains the exclusive LED test, and we can see there are 4 levels of LED brightness (Off, Minimum, Middle and Maximum).





In addition to this, the 5963/5964 test menu is also kept, which reveals more interesting information about this calculator. Let’s check the volume info first:


Graph Math+'s volume info.


fx-CG50's volume info.

As I expect, the calculator storage uses FAT12 format, which happens to be unsupported by many Android phones. I complained about this around 5 years ago when I received my fx-9750GIII, only to find out FAT12 was probably the main issue. In contrast, the previous generations all use FAT16 which has a greater compatibility with Android.

Back to the first page, there is an extra option named "etc" which is not present in fx-CG50. Selecting it brings up an pop-up which contains the much needed feature: Screen Receiver! It also works perfectly with Cahute. Hopefully it will be officially added soon in the future OS version.



MPM and add-ins

It’s time for some real fun. The Math+ Mod (MPM) brings back the add-in support for fx-CG100/Graph Math+ and I express my gratitude to all the MPM developers. Instructions for using MPM are available here: https://www.planet-casio.com/Fr/forums/topic18534-8-mpm-mod-add-ins-math.html

As soon as I received my Math+, I immediately modded it and had fun with SlyVTT’s SDL Tetris.

After that, I spent a few days rewriting the core part of the overlocking tool (Ptune3) in gint to see how fast my Math+ can run. Since Math+ shares almost the same hardware with fx-CG50, Ptune4 has the same mechanism as Ptune3 that auto adjusts the clock divisors to stay within safe ratios.

Here is the overclocking result:



My Math+ is only one PLL level shy of my fx-CG50. Still both calculators are apparently very capable of overclocking.

Verdict: ★★★⯨ (3.5/5 stars)

Casio has done a pretty good job on hiding the technical side from new students and put more focus on intuitive instructions and interactions. On the other hand, due to the drastic changes on UI and key layouts, experienced Casio users who are used to the traditional function key based habits may feel alienated from the new philosophy of the calculator. On top of that, it still has many missing features from the more established fx-CG50, while being listed at around the same price as Graph 90+E in France, making the new calculator the downgrade version.

Funnily enough, the Math+ offer from Germany is much cheaper than those from the French merchants, and it's still true even including the expensive shipping fee to HK! The fact that my Math+ has travelled across half of the globe and still costs less than the one sold locally just feels not right to me.

It's only worthy if you can get this calculator within 60 €, otherwise you are better off choosing fx-CG50/Graph 90+E while it lasts.

References

https://egadget.blog.fc2.com/blog-entry-825.html
https://www.planet-casio.com/Fr/forums/topic17774-1-test-graph-math-de-rentree-2024-la-graphique-couleur-entierement-repensee-par-casio.html (Recommended to read it as well because it's far more comprehensive!)