Many functions provide status and error information, either returning BLE_SUCCESS or BLE_CHECK_ERROR, in which case the variable ble.error can be checked for the specific error. This is done for consistency because not all error-causing events return directly to the main sketch. Functions used to get data may set ble.error even though they are not able to return BLE_SUCCESS or BLE_CHECK_ERROR. The possible errors are listed here:

If the offending function encapsulates many commands (e.g. HCI commands), the user can check ble.opcode for the specific command parameter. This is not set by most functions.