Datasheet

SST26VF032B / SST26VF032BA
DS20005218E-page 30  2013-2016 Microchip Technology Inc.
5.24 Write Suspend During Page
Programming or SPI Quad Page
Programming
Issuing a Write-Suspend instruction during Page Pro-
gramming allows the host to erase or read any sector
that is not being programmed. Erase commands point-
ing to the suspended sector(s) will be ignored. Any
attempt to read from the suspended page will output
unknown data because the program will be incomplete.
To execute a Write Suspend operation, the host drives
CE# low, sends the Write Suspend command cycle
(B0H), then drives CE# high. The Status register indi-
cates that the programming has been suspended by
changing the WSP bit from ‘0’ to ‘1,’ but the device will
not accept another command until it is ready. To deter-
mine when the device will accept a new command, poll
the BUSY bit in the Status register or wait T
WS
.
5.25 Write-Resume
Write-Resume restarts a Write command that was sus-
pended, and changes the suspend status bit in the Sta-
tus register (WSE or WSP) back to ‘0’.
To execute a Write-Resume operation, the host drives
CE# low, sends the Write Resume command cycle
(30H), then drives CE# high. To determine if the inter-
nal, self-timed Write operation completed, poll the
BUSY bit in the Status register, or wait the specified
time T
SE
, T
BE
or T
PP
for Sector-Erase, Block-Erase, or
Page-Programming, respectively. The total write time
before suspend and after resume will not exceed the
uninterrupted write times T
SE
, T
BE
or T
PP
.
5.26 Read Security ID
The Read Security ID operation is supported in both
SPI and SQI modes. To execute a Read Security ID
(SID) operation in SPI mode, the host drives CE# low,
sends the Read Security ID command cycle (88H), two
address cycles, and then one dummy cycle. To execute
a Read Security ID operation in SQI mode, the host
drives CE# low and then sends the Read Security ID
command, two address cycles, and three dummy
cycles.
After the dummy cycles, the device outputs data on the
falling edge of the SCK signal, starting from the speci-
fied address location. The data output stream is contin-
uous through all SID addresses until terminated by a
low-to-high transition on CE#. See Table 5-5 for the
Security ID address range.
5.27 Program Security ID
The Program Security ID instruction programs one to
2040 Bytes of data in the user-programmable, Security
ID space. This Security ID space is one-time program-
mable (OTP). The device ignores a Program Security
ID instruction pointing to an invalid or protected
address, see Table 5-5. Prior to the program operation,
execute WREN.
To execute a Program SID operation, the host drives
CE# low, sends the Program Security ID command
cycle (A5H), two address cycles, the data to be pro-
grammed, then drives CE# high. The programmed data
must be between 1 to 256 Bytes and in whole Byte
increments.
The device handles shifting of more than 256 Bytes of
data by maintaining the last 256 Bytes of data as the
correct data to be programmed. If the target address for
the Program Security ID instruction is not the beginning
of the page boundary, and the number of data input
exceeds or overlaps the end of the address of the page
boundary, the excess data inputs wrap around and will
be programmed at the start of that target page.
The Program Security ID operation is supported in both
SPI and SQI mode. To determine the completion of the
internal, self-timed Program SID operation, poll the
BUSY bit in the software status register, or wait T
PSID
for the completion of the internal self-timed Program
Security ID operation.
TABLE 5-5: PROGRAM SECURITY ID
Program Security ID Address Range
Unique ID Pre-Programmed at factory 0000 – 0007H
User Programmable 0008H – 07FFH