GD25LQ40xIGx 1.8V Uniform Sector Dual and Quad Serial Flash
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7.32. Burst Read with Wrap (0CH)
The “Burst Read with Wrap (0CH)” command provides an alternative way to perform the read operation with
“Wrap Around” in QPI mode. This command is similar to the “Fast Read (0BH)” command in QPI mode, except
the addressing of the read operation will “Wrap Around” to the beginning boundary of the “Wrap Around” once
the ending boundary is reached. The “Wrap Length” and the number of dummy clocks can be configured by the
“Set Read Parameters (C0H)” command.
Figure 34. Burst Read with Wrap command Sequence Diagram
CS#
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14
SCLK
IO0
IOs switch from
Input to output
Command
0CH
20 16 12
21 17 13
8
9
4
5
6
7
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
IO1
IO2
IO3
22 18 14 10
23 19 15 11
A23-16 A15-8
A7-0
Byte1 Byte2 Byte3
Dummy*
*"Set Read Parameters" Command (C0H)
can set the number of dummy clocks
7.33. Enable QPI (38H)
The device support both Standard/Dual/Quad SPI and QPI mode. The “Enable QPI (38H)” command can
switch the device from SPI mode to QPI mode. See the command Table 2a for all support QPI commands. In
order to switch the device to QPI mode, the Quad Enable (QE) bit in Status Register-1 must be set to 1 first,
and “Enable QPI (38H)” command must be issued. If the QE bit is 0, the “Enable QPI (38H)” command will
be ignored and the device will remain in SPI mode. When the device is switched from SPI mode to QPI mode,
the existing Write Enable Latch and Program/Erase Suspend status, and the Wrap Length setting will remain
unchanged.
Figure 35. Enable QPI mode command Sequence Diagram
CS#
0
1
2
3
4
5
6
7
SCLK
SI
Command
38H
Rev.1.0
59 - 47
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