ACE25C400

4MB Serial Flash Memory

VER 1.2

13

Figure 8 Writes status register instruction

Read Data (03h)

The Read Data instruction allows one or more data bytes to be sequential ly read from the memory.

The instruction is initiated by driving the CS# pin low and then shifting the instruction code “03h”

followed by a 24-bit address A23-A0 into the DI pin. The code and address bits are latched on the

rising edge of the CLK pin. After the address is received, the data byte of the addressed memory

location will be shifted out on the DO pin at the falling edge of CLK with most significant bit (MSB) first.

The address is automatically incremented to the next higher address after each byt e of data is shifted

out allowing for a continuous stream of data. This means that the entire memory can be accessed with

a single instruction as long as the clock continues. The instruction is completed by driving CS# high.

The Read Data instruction sequence is shown in Figure 9. If a Read Data instruction is issued while

an Erase, Program or Write cycle is in process (WIP =1) the instruction is ignored and will not have

any effects on the current cycle. The Read Data instruction allows clock rates fr om D.C. to a

The Read Data (03h) instruction is only supported in Standard SPI mode.

Figure 9 Read data instruction