W25Q32BV_13 Datasheet, PDF (39/78 Pages) Winbond – 3V 32M-BIT SERIAL FLASH MEMORY WITH DUAL AND QUAD SPI

W25Q32BV
7.2.18 Set Burst with Wrap (77h)
The Set Burst with Wrap (77h) instruction is used in conjunction with “Fast Read Quad I/O” and “Word
Read Quad I/O” instructions to access a fixed length of 8/16/32/64-byte section within a 256-byte page.
Certain applications can benefit from this feature and improve the overall system code execution
performance.
Similar to a Quad I/O instruction, the Set Burst with Wrap instruction is initiated by driving the /CS pin low
and then shifting the instruction code “77h” followed by 24 dummy bits and 8 “Wrap Bits”, W7-0. The
instruction sequence is shown in Figure 17. Wrap bit W7 and the lower nibble W3-0 are not used.
W6, W5
00
01
10
11
W4 = 0
Wrap Around
Wrap Length
Yes
8-byte
Yes
16-byte
Yes
32-byte
Yes
64-byte
W4 =1 (DEFAULT)
Wrap Around Wrap Length
No
N/A
No
N/A
No
N/A
No
N/A
Once W6-4 is set by a Set Burst with Wrap instruction, all the following “Fast Read Quad I/O” and “Word
Read Quad I/O” instructions will use the W6-4 setting to access the 8/16/32/64-byte section within any
page. To exit the “Wrap Around” function and return to normal read operation, another Set Burst with
Wrap instruction should be issued to set W4 = 1. The default value of W4 upon power on is 1. In the case
of a system Reset while W4 = 0, it is recommended that the controller issues a Set Burst with Wrap
instruction to reset W4 = 1 prior to any normal Read instructions since W25Q32BV does not have a
hardware Reset Pin.
/CS
CLK
Mode 3
Mode 0
IO₀
IO₁
IO₂
IO₃
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Mode 3
Instruction (77h)
don't
care
don't
care
don't
care
Wrap Bit
Mode 0
X X X X X X w4 X
X X X X X X w5 X
X X X X X X w6 X
XXXXXXXX
Figure 17. Set Burst with Wrap Instruction Sequence
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Publication Release Date: October 04,2013
Revision I