in Mobile phones, Reversing

My old Siemens patches

Siemens SL45i (or SL45, SL42 – it’s the same phone) is – in my opinion – the best cellphone of it’s time. I spend a lot of time reversing it’s software and try to making it better by developing patches. Scene of patching this phone was very busy, hundred of patches was developed. In some point, RizaPN, most recognizable patchmaker created “Binary File Access” – patch that allow us to load and run executable files from memory card. I’ve developed some of that files, even wrote a simple game. I collected all patches which I still have. Some of them are missing, so it is not complete pack, but the most important ones are present. If you have any of my missing patches – please contact me.

Some of the most productive patchmakers which I’d like to recall are: RizaPN, lalo.lerry, mamaich, Chaos, DeadManS, rc-flitzer, ValeraVi, vBart and many others. Thank you guys.

My patches for Siemens SL45i – pack of V-Klay patches contains Thermometer v1.2, MP3 indicators v3.1, Fast animated logo, Green button function, Playlist MP3 instead, Buttons Animation, Band selection and Auto OC. Some of them are documented with assembler source code.

My apps for Siemens SL45i – pack of binary executable files (bin) contains Archer (simply arcade game), Playlist Converter, Thermometer v1.1 and OC Info. With sources.

Siemens SX1 – I developed several flash patches between March and December of 2007. This patches are in sxpr format – it is APatcher format. Just to see files you could use Microsoft Word, Wordpad or OpenOffice Writer. This files contain some Wordpad formatting so it is not convenient to open them in notepad.

My patches for Siemens SX1 – all my patches are collected in single archive. The most complex one (date and profile name in mainscreen) contain assembler source. List of patches in archive: Disable Low Battery Message and sound, Don’t change backlight level in camera, Change camera standby timer, Change camera standby timer v2, Disable Selected profile message, Don’t display profile name in mainscreen, Display date and profile name symbol in mainscreen, Don’t show OpLogo picture, Display date and profile name symbol in mainscreen v2, Don’t show profiles in shutdown menu.

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  1. I’ve got an old Siemens S46 that I’d like to take a crack at reverse-engineering. Any tips or pointers? Looks like the sl45 used an infineon C166 micro .. I haven’t cracked open the S46 yet, but I wonder if they kept that design.

  2. If it is really C166, firmware should be similar to SL45 and other old Siemens. You could try to port some patches for these phones. IMHO easiest way to do that is to try to locate hex strings from original patches (skipping addresses and other position dependent stuff of course) and starts to adjust these addresses.
    You could find this patches here:
    Good luck 🙂

  3. Hello,

    I recently found my old A55 on the attic and now I’m interested in romhacks for the first time. I realise it’s kind of late to become interested in this antique phone and most information has already vanished from the web but it’s nice to discover someone who previously worked on that. Thanks for putting up your patches.

    Just wondering: Did you have any success loading a full SL45 backup using IDA Pro? Do you maybe have a memory map of the EGOLDv3 chip or any idea where I could find one?

    I’m looking forward to hear from you and left you my real email address for that reason 😉

  4. Hi,
    I had IDA database from this guy – . It was complete image dump. I may still have this (and more) somewhere on CD, I could try to find that.