A memory system is constituted of a file storage flash memory storing a control program required for a control portion and a large amount of data, and a random access memory storing a program used by the control portion and functioning as a buffer memory for received data. Thus, a memory system for a portable telephone capable of storing a large amount of received data at high-speed and allowing reading of the stored data at high-speed is provided.

A memory system is constituted of a file storage flash memory storing a control program required for a control portion and a large amount of data, and a random access memory storing a program used by the control portion and functioning as a buffer memory for received data. Thus, a memory system for a portable telephone capable of storing a large amount of received data at high-speed and allowing reading of the stored data at high-speed is provided.