TiLDA MK4/sim800/Reverse engineering

This page represents an effort to find out more about the inner workings of the SIM800 module found on the TiLDA MK4 badge.

Feel free to add your own research, but please do not remove content added by other people, even if you determined the information to be false. Instead you could add text explaining why the existing content was wrong.

Usefull links

Page with firmware, update tool and instructions: https://www.raviyp.com/embedded/214-learn-how-to-update-the-firmware-of-your-sim800-modules Information about Mediatek chipsets: https://www.bunniestudios.com/blog/?p=4297 Information on Mediatek file formats: https://wiki.postmarketos.org/wiki/Mediatek#Image_format

Current state of research

Based on the flashing utility and firmware file provided on the raviyp website the SIM800 module probably contains a Mediatek dumb-phone chipset. Bunny did some research on those already, which can be found on his [[1]].

To-do list

- Removing the lid from a SIM800 module and taking photos of the insides
- Figuring out exactly which (Mediatek) chip is inside the SIM800
- Find a way to replace the built-in ringtones
- ???
- Profit!