FM25Q32
11.2.32 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 Set Burst with Wrap Instruction Sequence.
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
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 FM25Q32 does
not have a hardware Reset Pin.
Set Burst with Wrap Instruction Sequence
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