Certain high-level settings can be configured using a filed named card10.cfg. It is accessed from the USB File Transfer of the bootloader. Once you are in this mode and have mounted the badge’s flash device, you can either create or update a file named card10.cfg.

The file is in the well-known INI-style format, with one setting per line. For instance, if there were an option called answer_to_life, you could set it by writing the following line in the card10.cfg file:

answer_to_life = 42

Don’t forget to unmount the filesystem before rebooting your badge after changing any setting.

Syntax and Types

Lines that start with a # character are ignored.

Any other line will have the overall syntax of option_name = option_value, with spaces around the = character optional.

Option names are internal to card10 and described below. Each option has a defined type.

Type name



A true/false value. 1 or true is true, 0 or false is false. Example: foo = true.


An unquoted string value of maximum 20 bytes. Values longer than 20 bytes are trimmed. Example: foo = bar.


A signed 32-bit integer in base 10. Example: foo = 42 or bar = -1337.


A single-precision (32-bit) floating-point number in base 10. Example: foo = 13.37.

Supported options

Option name





Allow running of binary l0dables. These files can be nefarious, so this option is off by default.