Micron M25P40 Serial Flash Embedded Memory
READ DATA BYTES
READ DATA BYTES
The device is first selected by driving chip select (S#) LOW. The command code for
READ DATA BYTES is followed by a 3-byte address (A23-A0), each bit being latched-in
during the rising edge of serial clock (C). Then the memory contents at that address is
shifted out on serial data output (DQ1), each bit being shifted out at a maximum fre-
quency fR during the falling edge of C.
The first byte addressed can be at any location. The address is automatically incremen-
ted to the next higher address after each byte of data is shifted out. Therefore, the entire
memory can be read with a single READ DATA BYTES command. When the highest ad-
dress is reached, the address counter rolls over to 000000h, allowing the read sequence
to be continued indefinitely.
The READ DATA BYTES command is terminated by driving S# HIGH. S# can be driven
HIGH at any time during data output. Any READ DATA BYTES command issued while
an ERASE, PROGRAM, or WRITE cycle is in progress is rejected without any effect on
the cycle that is in progress.
Figure 13: READ DATA BYTES Command Sequence
0
7
8
Cx
C
LSB
A[MIN]
DQ[0]
DQ1
Command
High-Z
MSB
A[MAX]
LSB
DOUT DOUT
DOUT
MSB
DOUT
DOUT
DOUT
DOUT
DOUT
DOUT
Don’t Care
1. Cx = 7 + (A[MAX] + 1).
Note:
PDF: 09005aef8456654f
m25p40.pdf - Rev. Y 8/12 EN
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