at25dq321a ATMEL Corporation, at25dq321a Datasheet - Page 49

• Manufacturer Part Number: at25dq321a
• Description: 32-megabit 2.7-volt Minimum Spi Serial Flash Memory With Dual-i/o And Quad-i/o Support
• Manufacturer: ATMEL Corporation

AT25DQ321A [Preliminary]
12.5
Hold
The HOLD pin is used to pause the serial communication with the device without having to stop or reset the clock
sequence. The Hold mode, however, does not have an affect on any internally self-timed operations such as a
program or erase cycle. Therefore, if an erase cycle is in progress, asserting the HOLD pin will not pause the
operation, and the erase cycle will continue until it is finished.
The Hold mode can only be entered while the CS pin is asserted. The Hold mode is activated simply by asserting
the HOLD pin during the SCK low pulse. If the HOLD pin is asserted during the SCK high pulse, then the Hold
mode won’t be started until the beginning of the next SCK low pulse. The device will remain in the Hold mode as
long as the HOLD pin and CS pin are asserted.
While in the Hold mode, the SO pin will be in a high-impedance state. In addition, both the SI pin and the SCK pin
will be ignored. The WP pin, however, can still be asserted or deasserted while in the Hold mode.
To end the Hold mode and resume serial communication, the HOLD pin must be deasserted during the SCK low
pulse. If the HOLD pin is deasserted during the SCK high pulse, then the Hold mode won’t end until the beginning
of the next SCK low pulse.
If the CS pin is deasserted while the HOLD pin is still asserted, then any operation that may have been started will
be aborted, and the device will reset the WEL bit in the Status Register back to the logical “0” state.
Figure 12-5. Hold Mode
CS
SCK
HOLD
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