Memory circuit of ACU7505 chip MP3 player

Shown is the memory circuit of an MP3 player using the ACU7505 chip. In order to meet the requirement of large data storage capacity when the CPU and decoder chip in the MP3
player are working, two memories are set up in the MP3 player. The composition of these two memory circuits is exactly the same.
They are both composed of K9KIG28UOM chip and peripheral circuits . The main pin functions of the memory are shown in the figure. Since the memory is a semiconductor
device, it also requires a DC power supply (vcc) when working.