Author Topic: More Precision on the 83+/84+ (10^127 - 10^-127)  (Read 4982 times)

0 Members and 1 Guest are viewing this topic.

thepenguin77

• z80 Assembly Master
• LV10 31337 u53r (Next: 2000)
• Posts: 1591
• Rating: +823/-5
• The game in my avatar is bit.ly/p0zPWu
More Precision on the 83+/84+ (10^127 - 10^-127)
« on: November 08, 2012, 11:29:26 pm »
Did you know that placing the maximum exponent at 10^99 was a completely arbitrary move by TI? In any case, I did, and I got rid of that limitation.

With this OS patch, your calculator can handle exponents from E-127 to E127.

I'm going to guess that TI added this limitation to keep up with their older calculators which only had room for a two digit number. They also probably kept it at two digits because they used a nice little hack to parse the numbers after the E token. But, in any case, I took off the bounds checking so that large numbers don't throw an ERR:OVERFLOW and modified the number parser to allow 3 digit numbers.

I made a patch for 1.19, 2.43, 2.53, and 2.55. The 2.55 is the ugliest of them all as I had to locate some code on page 00 (which could potentially mean compatibility issues with other patches), but they all work.

If you understand how TI-floats work, you might be wondering why I didn't allow E-128, and the reason for this is that there's a certain routine which could underflow back to E127, and that would just cause weird issues that I don't want to deal with. So E-127 is the limit.

I included the patcher with it's patch files if you want to see what is going on.

Edit:
And like always, there's an option to undo the patch.
« Last Edit: November 09, 2012, 01:56:29 pm by thepenguin77 »
zStart v1.3.013 9-20-2013
All of my utilities
TI-Connect Help
You can build a statue out of either 1'x1' blocks or 12'x12' blocks. The 1'x1' blocks will take a lot longer, but the final product is worth it.
-Runer112

Sorunome

• Fox Fox Fox Fox Fox Fox Fox!
• Support Staff
• LV13 Extreme Addict (Next: 9001)
• Posts: 7918
• Rating: +374/-13
• Derpy Hooves
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #1 on: November 08, 2012, 11:32:44 pm »
wow, that is awesome!
So that program patches the os and afterwards i can delete it again? epic!
 THE GAMEAlso, check out my websiteIf OmnomIRC is screwed up, blame me!Click here to give me an internet!

Builderboy

• Physics Guru
• CoT Emeritus
• LV13 Extreme Addict (Next: 9001)
• Posts: 5673
• Rating: +613/-9
• Would you kindly?
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #2 on: November 08, 2012, 11:39:41 pm »
That doesn't sounds like more precision at all!  That sounds like a larger range with the same amount of precision

Sorunome

• Fox Fox Fox Fox Fox Fox Fox!
• Support Staff
• LV13 Extreme Addict (Next: 9001)
• Posts: 7918
• Rating: +374/-13
• Derpy Hooves
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #3 on: November 08, 2012, 11:40:16 pm »
BTW, just tested and it is awesome!
While patching, what do the letters in the lower left corner mean?
 THE GAMEAlso, check out my websiteIf OmnomIRC is screwed up, blame me!Click here to give me an internet!

thepenguin77

• z80 Assembly Master
• LV10 31337 u53r (Next: 2000)
• Posts: 1591
• Rating: +823/-5
• The game in my avatar is bit.ly/p0zPWu
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #4 on: November 08, 2012, 11:46:52 pm »
That doesn't sounds like more precision at all!  That sounds like a larger range with the same amount of precision

Yeah, I totally realize that. But I don't know what else to call it.
zStart v1.3.013 9-20-2013
All of my utilities
TI-Connect Help
You can build a statue out of either 1'x1' blocks or 12'x12' blocks. The 1'x1' blocks will take a lot longer, but the final product is worth it.
-Runer112

Hayleia

• Programming Absol
• Coder Of Tomorrow
• LV12 Extreme Poster (Next: 5000)
• Posts: 3367
• Rating: +393/-7
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #5 on: November 09, 2012, 02:28:38 am »
I just tried it on my 84+SE, it is great
Is there a way to make it work on the 83+ too ?
I own: 83+ ; 84+SE ; 76.fr ; CX CAS ; Prizm ; 84+CSE
Sorry if I answer with something that seems unrelated, English is not my primary language and I might not have understood well. Sorry if I make English mistakes too.

click here to know where you got your last +1s

calc84maniac

• eZ80 Guru
• Coder Of Tomorrow
• LV11 Super Veteran (Next: 3000)
• Posts: 2898
• Rating: +467/-17
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #6 on: November 09, 2012, 02:30:35 am »
I just tried it on my 84+SE, it is great
Is there a way to make it work on the 83+ too ?
He mentioned the patch works on OS 1.19, so I assume that means TI-83+ is supported.
"Most people ask, 'What does a thing do?' Hackers ask, 'What can I make it do?'" - Pablos Holman

Hayleia

• Programming Absol
• Coder Of Tomorrow
• LV12 Extreme Poster (Next: 5000)
• Posts: 3367
• Rating: +393/-7
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #7 on: November 09, 2012, 02:31:48 am »
I just tried it on my 84+SE, it is great
Is there a way to make it work on the 83+ too ?
He mentioned the patch works on OS 1.19, so I assume that means TI-83+ is supported.
That is what I thought too but I didn't want to be the one that crashed a calc for more precision
And the title only mentions the 84+ so I really had doubts.
I own: 83+ ; 84+SE ; 76.fr ; CX CAS ; Prizm ; 84+CSE
Sorry if I answer with something that seems unrelated, English is not my primary language and I might not have understood well. Sorry if I make English mistakes too.

click here to know where you got your last +1s

aeTIos

• Nonbinary computing specialist
• LV12 Extreme Poster (Next: 5000)
• Posts: 3913
• Rating: +184/-32
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #8 on: November 09, 2012, 03:54:17 am »
Woo, thepenguin strikes again
I'm not a nerd but I pretend:

Juju

• Incredibly sexy mare
• Coder Of Tomorrow
• LV13 Extreme Addict (Next: 9001)
• Posts: 5730
• Rating: +500/-19
• Weird programmer
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #9 on: November 09, 2012, 08:49:20 am »
Yeah, I knew about this a while ago while messing up with Calcsys and changing the exponent part of a variable to higher than 99 and it worked The mantissa part is in BCD, so if you manage to increase the size of the mantissa field you would indeed get more precision. And if you increase the size of the exponent field, you would get numbers up to 10^65535. As always, nice OS patch.

Remember the day the walrus started to fly...

I finally cleared my sig after 4 years you're happy now?

This signature is ridiculously large you've been warned.

The cute mare that used to be in my avatar is Yuki Kagayaki, you can follow her on Facebook and Tumblr.

Xeda112358

• they/them
• Moderator
• LV12 Extreme Poster (Next: 5000)
• Posts: 4659
• Rating: +718/-6
• Calc-u-lator, do doo doo do do do.
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #10 on: November 09, 2012, 08:55:08 am »
Yay, now it works like some of the older calcs I saw I think a friend of mine had a TI-86 or TI-85 that could use numbers up to 10^127.

Juju

• Incredibly sexy mare
• Coder Of Tomorrow
• LV13 Extreme Addict (Next: 9001)
• Posts: 5730
• Rating: +500/-19
• Weird programmer
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #11 on: November 09, 2012, 08:57:16 am »
I think the TI-89 was also similarly constrained, as in only allowing numbers up to 10^999. Unless they use BCD for the exponent, it probably goes up to 1023.

Remember the day the walrus started to fly...

I finally cleared my sig after 4 years you're happy now?

This signature is ridiculously large you've been warned.

The cute mare that used to be in my avatar is Yuki Kagayaki, you can follow her on Facebook and Tumblr.

Lionel Debroux

• LV11 Super Veteran (Next: 3000)
• Posts: 2135
• Rating: +290/-45
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #12 on: November 09, 2012, 09:10:38 am »
The TI-68k series uses binary for the exponent, BCD for the mantissa. Exponents can go between -16383 to +16382, but most math functions don't like exponents below -999 or above +999.
( http://debrouxl.github.com/gcc4ti/timath.html#bcd )
Member of the TI-Chess Team.
Co-maintainer of GCC4TI (GCC4TI online documentation), TILP and TIEmu.

Yeong

• Not a bridge
• LV12 Extreme Poster (Next: 5000)
• Posts: 3739
• Rating: +278/-12
• Survivor of Apocalypse
Re: More Precision on the 84+ (10^127 - 10^-127)
« Reply #13 on: November 09, 2012, 09:30:45 am »
Thank you penguin. You did a great job yet again.
Sig wipe!

• Editor
• LV10 31337 u53r (Next: 2000)
• Posts: 1708
• Rating: +229/-17
Re: More Precision on the 83+/84+ (10^127 - 10^-127)
« Reply #14 on: November 09, 2012, 03:36:09 pm »
Btw, I showed this topic to a TI employee (a z80 master ) and he said it's awesome (or, well, at least talking about all of us here : "Those guys are awesome")
« Last Edit: November 09, 2012, 03:36:23 pm by adriweb »
My calculator programs