Re: LZ: Blank Memory Backup
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John Yuschak wrote:
>
> To those who want to HELP,
>
> I have pasted together a text file that is a map of a blank backup. I cleared my memory, and sent a backup to the computer, then hex viewed it.
What I want to
>
> Has this been done before?
> Do you have any additions (your name will be added to the file)?
> Is this map useless, and a waste of time?
> Is is helpful?
> Would you use it?
>
> I am sorta new, and I just want to contribute. If this is a bad idea, please tell me by word (not by flame). BTW, any ideas for a ZShell math
program (High Sch
>
> jyuschak@i21.com
>
>
>
> ---------------------------------------------------------------
>
> ******************************************************************
> * TEXAS INSTRUMENTS 85 CALCULATOR *
> * MEMORY MAP *
> * *
> * JOHN YUSCHAK *
> ******************************************************************
>
> This file is a result of my undertaking to understand the memory
> of the TI-85. I have analyized and re-analyized the TI-85 backups,
> and have found out where things are. Most things I still do not
> yet understand, but please bear with me. Also, I would like to
> thank David Boozer, for his knowledge of variables.
>
> ******************
> *** Memory Map ***
> ******************
>
> Offset Purpose or Desription
> --------- --------------------------------
> 0000-0034 File header
> 0035-08b0 ???
> 08b1-08ce Custom menu text
> 08cf-0914 ???
> 0915-091b Ans variable
> 091c-0924 yStat variable
> 0925-092d xStat variable
> 092e-092f Checksum
>
> *******************
> *** File Header ***
> *******************
>
> The backup file header contains information on what date the
> was created, and what time. The file header usually looks like
> this:
>
> **TI85** Backup file dated XX/XX/XX, XX:XX
>
> Where X is replaced with the needed information. This information
> is not useful to the user, only if he/she needs to know when the
> last backup was made.
>
> ************************
> *** Custom Menu Text ***
> ************************
>
> The offsets 08b1-08ce contain the text of which make up the custom
> menu. Every 2 bytes make up one menu. For instance, the offsets
> 08b1 and 08b2 make up the first custom menu. These bytes can be
> rearranged (in groups of 2), in effect, moving the contents of
> each menu.
>
> **********************
> *** Variable Bytes ***
> **********************
>
> The variable bytes are arranged in a special format recognized by
> the TI-85. For example purposes, we will use the Ans variable.
> Here are the bytes for Ans:
>
> 73 6e 41 03 8b fb 00
> --------------------
> Byte 1 2 3 4 5 6 7
>
> Here is the format of those bytes:
>
> Byte(s) Purpose or Description
> ------- -------------------------------------------------
> 1,2,3 Contains the name of the variable backwards
> 4 Contains the # of characters in the variable name
> 5,6 Contains the address of the variable in memory
> 7 Contains the type of the variable
>
> Note: This table does not hold for all variables, since
> all variable names are not 3 bytes in length.
>
> This file will not go any more in-depth with topic. For a more
> detailed look at variables and related, pick up "Hacking the
> TI-85 Calculator" by David Boozer. His file includes the above
> table, and more in-depth information.
Yes, you mentioned hacking the 85. That's a good one, and TI-ram.txt,
which was just updated, contains a good memory map, but not very
descriptive.
<pre>
--
Compliments of:
_-_-_-_-_-_-_-_
Alan Bailey
mailto:bailala@mw.sisna.com
IRC:Abalone
Web:http://www.mw.sisna.com/users/bailala/home.htm
</pre>
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