# Return Codes Most of the SDK's API functions return a `voltix_rc_t` that indicates the status of the transaction. There are a number of common return codes defined in `core/include/voltix.h`. Modules can additionally define their own return codes starting at a module-specific offset, which is also defined in `core/include/voltix.h`. Long-running interactions with peripherals may be interrupted by a reset or a teardown event. To ensure correct application execution, always check the return codes of such functions for the return values `VOLTIX_ERR_RESET` and `VOLTIX_ERR_TEARDOWN`. If a function call failed with one of these return codes, the application can, for example, wait until the capacitor is fully charged with `voltix_wait_cap_charged()` before trying again.