FOR MOBILE APPLICATIONS
W25Q256FV
Publication Release Date: May 13, 2012
- 82 - Preliminary - Revision M1
8.2.44
Set Read Parameters (C0h)
In QPI mode, to accommodate a wide range of applications with different needs for either maximum read
frequency or minimum data access latency, “Set Read Parameters (C0h)” instruction can be used to
configure the number of dummy clocks for “Fast Read (0Bh)”, “Fast Read Quad I/O (EBh)” & “Burst Read
with Wrap (0Ch)” instructions, and to configure the number of bytes of “Wrap Length” for the “Burst Read
with Wrap (0Ch)” instruction.
In Standard SPI mode, the “Set Read Parameters (C0h)” instruction is not accepted. The dummy clocks
for various Fast Read instructions in Standard/Dual/Quad SPI mode are fixed, please refer to the
Instruction Table 1-3 for details. The “Wrap Length” is set by W5-4 bit in the “Set Burst with Wrap (77h)”
instruction. This setting will remain unchanged when the device is switched from Standard SPI mode to
QPI mode.
The default “Wrap Length” after a power up or a Reset instruction is 8 bytes, the default number of
dummy clocks is 2. The number of dummy clocks is only programmable for “Fast Read (0Bh)”, “Fast
Read Quad I/O (EBh)” & “Burst Read with Wrap (0Ch)” instructions in the QPI mode. Whenever the
device is switched from SPI mode to QPI mode, the number of dummy clocks should be set again, prior to
any 0Bh, EBh or 0Ch instructions.
P5 – P4
DUMMY
CLOCKS
MAXIMUM
READ FREQ.
MAXIMUM
READ FREQ.
(A[1:0]=0,0)
MAXIMUM
READ FREQ.
(A[1:0]=0,0
VCC=3.0V~3.6V)
P1 – P0
WRAP
LENGTH
0 0
2 33MHz 50MHz 60MHz
0 0
8-byte
0 1
4 66MHz 80MHz 104MHz
0 1
16-byte
1 0
6 104MHz 104MHz 133MHz
1 0
32-byte
1 1
8 104MHz 104MHz 133MHz
1 1
64-byte
/CS
CLK
Mode 0
Mode 3
0
1
2
3
IO
0
IO
1
IO
2
IO
3
C0h
Read
Parameters
P4
P0
P5
P1
P6
P2
P7
P3
Instruction
Mode 0
Mode 3
Figure 48. Set Read Parameters Instruction (QPI Mode only)