ACE25AC400NLX

SPI NOR FLASH

VER 1.1

9

Read Data Bytes (READ) (03H)

The Read Data Bytes (READ) command is followed by a 3-byte address (A23-A0), each bit being

latched-in during the rising edge of SCLK. Then the memory content, at that address, is shifted out on SO,

each bit being shifted out, at a Max frequency fR, during the falling edge of SCLK. The first byte

addressed can be at any location. The address is automatically incremented to the next higher address

after each byte of data is shifted out. Therefore, the whole memory can be read with a single Read Data

Bytes (READ) command. During an Erase, Program or Write cycle, Read Data Byte (READ) command

will be rejected without affecting the cycle in progress.

Read Data Bytes At Higher Speed (Fast Read) (0BH)

The Read Data Bytes at Higher Speed (Fast Read) command is for quickly reading data out. It is followed

by a 3-byte address (A23-A0) and a dummy byte, each bit being latched-in during the rising edge of SCLK.

Then the memory content, at that address, is shifted out on SO, each bit being shifted out, at a Max

frequency fC, during the falling edge of SCLK. The first byte address can be at any location. The address

is automatically incremented to the next higher address after each byte of data is shifted out.

Figure5. Read Data Bytes Sequence Diagram

Figure6. Read Data Bytes at Higher Speed Sequence Diagram