I made a device that stores a previously generated password in EEPROM and inputs it to PC every time the device is connected.
Main Parts:
Circuit Diagram:
The device implements the USB boot HID keyboard protocol so once plugged in, the device can receive keyboard LED state changes (caps lock, num lock, scroll lock), which are used in the firmware to trigger new password generation (four LED toggle messages, i.e. four caps lock presses).
How to Fix circuit in USB :
Randomness for the generated password is also taken from LED state change timings - ATtiny85 timer is left running and every time an additional state change happens, lower 6 bits in TCNT0 are used to add one character to the password - so for a new 10-character password (default setting), a total of 4+10 caps lock presses generate a new password, which is stored in EEPROM.
Download Source Code and Full Documentation .
Main Parts:
The device implements the USB boot HID keyboard protocol so once plugged in, the device can receive keyboard LED state changes (caps lock, num lock, scroll lock), which are used in the firmware to trigger new password generation (four LED toggle messages, i.e. four caps lock presses).
How to Fix circuit in USB :
Download Source Code and Full Documentation .
