Re: A83: Converting TI-83+ Flash ROM upgrade to binary
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Re: A83: Converting TI-83+ Flash ROM upgrade to binary
I doubt VTI know how to use the update yet, so you'd have to have a rom
image
Jeff Tyrrill wrote:
>
> Yep, IntelHex is the format. I found some documents explaining the format,
> so I'll either write a program to decode it or do a longer search to find a
> freeware decoder. Thanks for your help.
>
> -----Original Message-----
> From: owner-assembly-83@lists.ticalc.org
> [mailto:owner-assembly-83@lists.ticalc.org]On Behalf Of Linus Akesson
> Sent: Sunday, September 26, 1999 1:56 PM
> To: assembly-83@lists.ticalc.org
> Subject: Re: A83: Converting TI-83+ Flash ROM upgrade to binary
>
> In accordance with the prophecy, Jeff Tyrrill uttered:
>
> > The new version of Virtual TI supports TI-83+ emulation, so I tried using
> > TI's Flash ROM upgrade file (base112.hex), until I realized it was in hex
> > and wouldn't work. So I wrote a program to convert it to binary, and
> filled
> > the file with 0's until the length was 256*1024 bytes. Then, VTI would
> > recognize it, and display it in the list of ROMs as TI-83 Plus version
> 1.12,
> > but it won't run; VTI just displays a blank TI-83+ screen and appears to
> > freeze.
>
> > To convert the hex file to binary, my program read the Base112.hex file
> and
> > processed all the lines of length 75 (it skipped over the rest), then
> > skipped the first 9 bytes of each of those lines so there were 66 bytes to
> > process, and then converted each dual-byte hex code to a single binary
> byte
> > and placed it in the binary file. Only 236742 bytes were filled that way,
> so
> > I filled with 0's up to 262144. Obviously the encoding method is more
> > complex than the above; it appears that the first 9 bytes of each line
> > indicate perhaps the location of the hex string in the assembled ROM, but
> my
> > program just assumed all the lines were in order, which they probably
> > weren't. However, I did find calculator text inside the binary file I
> > created (such as various TI-83 commands), so I know the file isn't
> > encrypted.
>
> > So, is there an easy way, or an already available conversion program, to
> > convert the TI's 83 hex ROM file to binary format so VTI can use it?
>
> That sounds a bit like the IntelHex format. I think every line begins with
> some kind of memory location, and ends with a checksum. You should be able
> to
> find info rather easily, searching for IntelHex somewhere.
>
> Linus
>
> - Linus Akesson ------------------------- http://linusworld.cjb.net -
> ::: :::. :.:: :. ::.. : :... ::.: ::. :::: :.:. :: :..: :.. :.: :....
>
> I think it would be a good idea.
> -- Mahatma Gandhi on Western civilization.
--
Scott "_Wrath_" Dial
wrath@calc.org
ICQ#3608935
TimeCity Co-Lead Developer, AI - www.timecity.org
Member of TCPA - tcpa.calc.org
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