Software reset – Rainbow Electronics AT45DB021E User Manual
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AT45DB021E [PRELIMINARY DATASHEET]
8789B–DFLASH–11/2012
13.
Software Reset
In some applications, it may be necessary to prematurely terminate a program or erase cycle early rather than wait the
hundreds of microseconds or milliseconds necessary for the program or erase operation to complete normally. The
Software Reset command allows a program or erase operation in progress to be ended abruptly and returns the device
to an idle state.
To perform a Software Reset, the CS pin must be asserted and a 4-byte command sequence of F0h, 00h, 00h, and 00h
must be clocked into the device. Any additional data clocked into the device after the last byte will be ignored. When the
CS pin is deasserted, the program or erase operation currently in progress will be terminated within a time t
SWRST
. Since
the program or erase operation may not complete before the device is reset, the contents of the page being programmed
or erased cannot be guaranteed to be valid.
The Software Reset command has no effect on the states of the Sector Protection Register, the Sector Lockdown
Register, or the Buffer and page size configuration.
The complete 4-byte opcode must be clocked into the device before the CS pin is deasserted; otherwise, no reset
operation will be performed.
Table 13-1. Software Reset
Figure 13-1. Software Reset
Command
Byte 1
Byte 2
Byte 3
Byte 4
Software Reset
F0h
00h
00h
00h
CS
SI
F0h
00h
00h
00h
Each transition represents eight bits