The present invention relates to a method of controlling a disk writing operation based on battery remaining capacity. This method is applicable to a portable device such as notebook and disk drive which use a battery as a power source. This present method detects a remaining capacity of an equipped battery, compares the detected remaining capacity with a reference capacity required for conducting normal completion of writing operation, and then, if the detected remaining capacity is lower than the reference, stops current writing operation and conducts completion of writing operation. As a result, it is possible to prevent disk damage caused from abnormal writing termination due to complete discharge of a battery in a notebook or a portable disk drive. |