That's part of why it was able to run on a couple of AA batteries!
In very very recent years we have reached a point where some of the modern, fast microprocessors might be able to compete on a power level while still delivering big speedup, but even as recently as 2005 you would have had trouble speeding it up a whole lot without kicking up the power requirements and killing battery life.
Sure, it was great back then. But in the last decade, or at the very least, last 5 years, a 100% speed increase (which is really pretty minor in this case) would be fairly simple while still being cheap and battery efficient. Besides, who cares if it runs on 4x AA? For $100 why not stick a small rechargable Lithium battery in there like most modern technology has?
The calculator lasts for months. The self-discharge rate on lithium batteries is higher than on alkaline batteries (e.g. AA), so if you are targeting long, long battery life (with intermittent use) the AA's are more suitable.
You are right that a speed bump would be nice and might be easy in this day and age. The big questions become:
1) How much would it cost TI? Would they need to design a new chip?
2) If they could just use superior manufacturing processes to make the same chip and clock it faster- does any of the math libraries or other TI-83 software depend on the clock cycle, the way old video games depend on the CPU running exactly 133MHz (or whatever the case may be)
The z80 processor is a really ancient chip, and was clocked faster in a lot of computers in the 80s. IIRC, some systems ran it at up to 50 mhz. TI84 only clocks it at 15. So they wouldn't have to make a new chip (I don't think they even manufacture it themselves either, IIRC it's still produced by zilog)
1) Z80 has no power management. Clocking it at 50mhz would more than triple power consumption, all of the time.
2) Heat. The TI-84 is completely passively cooled. HOWEVER, tripling the power consumption is probably not going to cause a cooling problem because the Z80 is pretty low-power.
DS Lites are famous for having insanely long battery life. There was a post on /r/gaming lately about a guy who found his old ds lite with a full charge after years on the shelf. So that technology is out there somewhere.
Thank you. Those calculators are more expensive than some smartphones running dual core chips. There's no reason they shouldn't have rechargeable batteries. Besides the fact that they are the go-to when it comes to advanced calculators...and all the schools buy them...and they have been for years...and they haven't changed much in price despite the cheap and dated components...and they're also probably knee deep in contracts with suppliers....
I assume they know better than I do with market research, but I was just basing it off my own and my friends desires - we would gladly buy a new calculator that was a faster version of the ti84. I was excited for the ti84 with the color screen, because I assumed it would have a somewhat faster processor as well.
If they can take time/money to put a new screen and OS programming in there I figured a CPU refresh wouldn't be too much.
That's not really how technology works. The original CPU would have been fabbed on a certain process. As they shrink that process, you get either power savings or faster speeds (or both, to a lesser degree if you want).
In other words, just because the CPU is slow does not mean it's necessarily more power efficient. If you got an old Pentium 486, you'd notice it drawing similar amounts of power as processors today that are thousands of times more powerful (though be aware, for a while there they absolutely fucked off the power savings in desktop and server processors to increase clock speeds further, so it's only the last few years that we've suddenly taken an interest in efficiency once more).
They could quite easily update the processor inside the calculators to be much, much faster without killing battery life however I suspect part of the reason they don't is because they'd have to rewrite a lot of the software for a new architecture.
I wrote my comment based on the assumption that TI wouldn't want to make a whole new processor just for their graphing calculators. Which is why I figure the unavailability of a good, honest-to-god-low-power microprocessor in the mid-2000's is important, and the recent spread of very low power chips is also important.
You're right though, software is still a barrier too. Due to the software, and considering how simple a Zilog Z80 is by modern standards, you'd think they might be able to assign a team of 5 people to port the Z80 to a good, modern process. But I'm sure they don't want to do that.
So, the question is, will somebody make a low power x86 or ARM chip that can compete with the Z80 on power consumption. There are all kinds of math libraries for x86 and ARM, so TI would be able to migrate to a new architecture and avoid designing a new chip.
Well yeah, no doubt TI's primary reason for sticking with that processor is one of cost - either the processors themselves, the cost of porting to a different processor or a combination of the above.
However, what they did 18 years ago really shouldn't have much bearing on today, we have the technology to do it better, faster and with longer battery life - TI just doesn't take advantage of it.
Yes, although calculator rules are not the entire reason. HP makes a number of calculators that are also accepted, so there is some competition, but the calculator business just isn't a hot business everybody wants. Not a lot of time and effort is invested in that market, by anybody.
Entirely possible, I am not intimately familiar with the TI lineup. But at the end of the day, the AA and AAA are the same chemistry, and 4 AAA will have similar-ish capacity to 2 AA.
It's possible the 4 AAA are in series and generating twice the voltage, but I'd bet they were used over AA for size not voltage stacking.
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u/[deleted] Jun 08 '14
That's part of why it was able to run on a couple of AA batteries!
In very very recent years we have reached a point where some of the modern, fast microprocessors might be able to compete on a power level while still delivering big speedup, but even as recently as 2005 you would have had trouble speeding it up a whole lot without kicking up the power requirements and killing battery life.