I loved their post on the iButton. https://blog.flipperzero.one/taming-ibutton/
I've never actually come across this interface. It's not common in Australia, I still really enjoyed the write up and seeing how they overcame the difficulties.
I've never actually come across this interface. It's not common in Australia, I still really enjoyed the write up and seeing how they overcame the difficulties.
The epoxy jobs I often see anchoring iButtons to walls visibly aren't at the level of detail/engineering required to run invisible wiring (eg through concrete) etc, so I theorize that the iButtons themselves are completely passive (eg, they contain a resistor, or maybe a microcontroller), and the box is a transponder (unlikely) or that it records to internal storage and then gets dropped onto a sync cradle (more likely).
The gadgets the cleaners use are very literally about as featureful as a cigarette packet: a dark grey rectangle with an iButton connector on the back and a small LCD. I've not really ever had the impetus to go pin a cleaner down and politely ask for more details :D
If EEPROM:
Level 0: Determine that it's an EEPROM and dump the full contents
Level 1: Locate the undocumented vendor control string (which doesn't exist) and unlocks the EEPROM and makes it fully rewritable
Level 2: Rewrite the EEPROM to change the area code or label or whatnot to something funny
Level 3.14159265359: Rewrite the EEPROM such that its contents cause a buffer overflow in the handheld gadget and achieve remote code execution
Level 42: Rewrite the EEPROM such that the RCE achieved in the handheld gadget then causes nested RCE in the synchronization software, then use the opportunity to, say, open a popular YouTube video
If Java:
Level 0: Send data through the iButton link that breaks the Java sandbox and allows for general execution on the CPU
Level 1: Dump the full contents of the firmware
Level 2: Alter the firmware such that every time you tap the iButton it sends area information from shopping centres in entirely different states (counties) :D
Level 3.1e10: Alter the firmware to achieve RCE in the scanner gadget, then stream individual video frames through the iButton link onto the scanner LCD :D