A smart card which includes a non-volatile read/write memory and a processor connected to the memory, and further configured to cause the processor to perform a method for enhancing data security and managing the contents of memory during periods when the computational power of the processor is underutilized. The method includes steps for determining if a command or character has been received, processing and/or responding to the command or character once received, implementing a security measure and/or managing memory, and performing a tamper protocol in response to detecting a security breach, all of which is performed while waiting to receive the next command or character.