AT26F004-SSU ATMEL [ATMEL Corporation], AT26F004-SSU Datasheet - Page 27

• Manufacturer Part Number: AT26F004-SSU
• Description: 4-megabit 2.7-volt Only Serial Firmware DataFlash Memory
• Manufacturer: ATMEL [ATMEL Corporation]

11.4
Figure 11-4. Hold Mode
3588A–DFLSH–10/05
Hold
HOLD
SCK
CS
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 the Hold mode will abort
and the device may abort the current operation depending on whether or not a complete
opcode, address bytes, or data byte was already clocked into the device before the Hold mode
was entered. The WEL bit in the Status Register will be reset back to a logical “0” if a program,
erase, Protect Sector, Unprotect Sector, or Write Status Register operation aborts as a result of
the Hold mode aborting.
Hold
Hold
Hold
AT26F004
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