The calculator of your dreams (or your fears)

[DarkestEx]

Personally I don't see any difference in this topic with the other, so I merged both, but if you obect, I can always split it back into a standalone topic.

The problem with TI calcs is that they're overpriced for their specs. Even the 150 MHz TI-Nspire CX with 100 MB of RAM/64 MB Flash is overpriced. On the other hand, it would be hard to make a community calculator as cheap as TI calcs should be, because production costs are much higher than when they produce calculators in bulk of thousands.

Well this was meant as some sort idea collection topic to see what we could do. I would like to have a community calc. And if we use the microcat's chipset i can reuse the bios, some of the drivers and mainly the hardware i have laying around.

It would be a 120MHz, 32 bit ARMv7ME, 64KB RAM, 256KB flash (native applications and basic)

[Dream of Omnimaga]

I think the Flash is too low. 256 KB is even less than the TI-84+, so basically you can only fit 1 game on the calc if it uses advanced graphics and only a few math applications would fit. That's unless external storage is supported, though.

[Dudeman313]

I'd want at least 1 TB of Flash on anything, with or without expandable storage.

[Lionel Debroux]

Both 64 KB of RAM and 256 KB of Flash are way too small, indeed.

[Unicorn]

I'd want at least 1 TB of Flash on anything, with or without expandable storage.

One TB on a calc? I would say about 10 gb would be enough, depending on the programs you can make with it.

[Dream of Omnimaga]

Considering that a standard sized 1 TB hard drive is $50, I would go smaller. If 1 TB is this expensive, then imagine how expensive it would be as a smaller storage medium that fits inside a calc.

[DarkestEx]

Well then it's not worth even trying to make some calculator. I would have only used parts from the microcat development. This was the second last chip we were testing. It's big brother would have been used in the microcat. The big brother has 128KB RAM and 512KB flash. Note that the flash is completely different to the one used in the TI calcs and is a lot more flexible. The big brother also has SD card support.

[Dudeman313]

The calculator of my fears would either be the TI-15 or the first one .

[Dream of Omnimaga]

One thing to keep in mind with making a community calculator should be to ensure that it can compete against the TI-84 Plus CE and Casio fx-CG20 from an hardware standpoint. It can have a smaller color screen and Z80 CPU, but if the calc RAM and Flash is even lower than the old 83+ or the original TI-89, or if it has a monochrome screen, then people won't really be interested, even if the price is low. You could get away by using a monochrome screen maybe, but only if it's backlit properly, like the FX-9860GII.

[DarkestEx]

One thing to keep in mind with making a community calculator should be to ensure that it can compete against the TI-84 Plus CE and Casio fx-CG20 from an hardware standpoint. It can have a smaller color screen and Z80 CPU, but if the calc RAM and Flash is even lower than the old 83+ or the original TI-89, or if it has a monochrome screen, then people won't really be interested, even if the price is low. You could get away by using a monochrome screen maybe, but only if it's backlit properly, like the FX-9860GII.

Color screen is ugly, expensive, slow and power consuming. It wouldn't be worth it.
Having a properly muxed grayscale screen would be way better.
Also z80 would certainly not be the platform of choice but arm for many, many reasons:
Cheap, fast, powerful, easy to get, low current, 32 bit, supports way more RAM without hacks (up to 4GB), USB, fast SPI (e.g. for screen or SD card)

For the community calc I can offer 120 MHz, 128 KB RAM, 16 MB flash from where native programs can run (without being loaded into RAM!)
Price estimation would be around 50€
The processor does support full speed USB 2.0 client + host and high speed SDIO over a HSMCI (SD cards).

[Dream of Omnimaga]

For the color screen, I was mostly refering to download stats on ticalc. Super Mario 1.2 used to average at 2000 downloads a week, and now it rarely makes the top 25 anymore. Most top 25 files are either school or shell related or color. It's your choice, though. Would a backlit monochrome screen be more expensive?

[Lionel Debroux]

I agree about the ISA of choice being ARM (Cortex-M4/-M7 for relatively high-powered yet power-efficient lower-end machines, Cortex-A5/-A32/-A35 for power-efficient higher-end machines), but I disagree about the backlit color screen. As DJ indicates, that ship has now sailed.

[Dream of Omnimaga]

I wonder if there is any page online that compares various type of LCDs for DYI pocket device projects?

[GalacticPirate]

Well, now just sit down and think a minute. If the Iphone 6S Plus or the Samsung Galaxy S7 edge were calculators (and only calcs), it would completely humiliate actual ones, and even at this price (~€700-1100), their value-for-money would be far better than TI's/Casio's/HP's one So, we are just in an impossible c with these outdated technologies

[DarkestEx]

Well, now just sit down and think a minute. If the Iphone 6S Plus or the Samsung Galaxy S7 edge were calculators (and only calcs), it would completely humiliate actual ones, and even at this price (~€700-1100), their value-for-money would be far better than TI's/Casio's/HP's one So, we are just in an impossible s*** with these outdated technologies

That is not the point of calculators. They don't need to be fancy after all. There is a lot of reasearch to them though TI seems to fail making good code and Casio's UI is such crap.

I don't see any benefit of a color screen in a calculator except graph plotting and some games, but it is not worth it. You will end up with having to charge it often and nobody wants to do that.
A monochrome screen would be a lot more reasonable.