w25q64dw Winbond Electronics Corp America, w25q64dw Datasheet - Page 63

• Manufacturer Part Number: w25q64dw
• Description: 1.8v 64m-bit Serial Flash Memory With Dual/quad Spi & Qpi
• Manufacturer: Winbond Electronics Corp America

10.2.38 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 10.2.2-10.2.4 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
0 0
0 1
1 0
1 1
CLOCKS
DUMMY
2
4
6
8
Figure 37. Set Read Parameters Instruction (QPI Mode only)
MAXIMUM READ
CLK
/CS
IO
IO
IO
IO
0
1
2
3
104MHz
30MHz
50MHz
80MHz
FREQ.
Mode 3
Mode 0
Instruction
- 63 -
0
C0h
READ FREQ.
(A[1:0]=0,0)
MAXIMUM
1
104MHz
104MHz
30MHz
80MHz
Parameters
P4
P5
P6
P7
Read
2
P0
P1
P2
P3
3
Publication Release Date: January 13, 2011
Mode 3
Mode 0
P1 – P0
0 0
0 1
1 0
1 1
Preliminary - Revision C
W25Q64DW
LENGTH
16-byte
32-byte
64-byte
WRAP
8-byte