©2010 Silicon Storage Technology, Inc.

S71409-01-000

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1.8V Serial Quad I/O (SQI) Flash Memory

SST26WF032

Advance Information

Program Security ID

The Program Security ID instruction programs one to 24 Bytes of data in the user-programmable,

Security ID space. The device ignores a Program Security ID instruction pointing to an invalid or pro-

tected address, see Table 7. Prior to the program operation, execute WREN.

To execute a Program SID operation, the host drives CE# low, sends the Program Security ID com-

mand cycle (A5H), one address cycle, the data to be programmed, then drives CE# high. The pro-

grammed data must be between 1 to 24 Bytes and in whole Byte increments; sending an odd number

of nibbles will cause the last nibble to be ignored. Each cycle is two nibbles long, most significant nib-

ble first. To determine the completion of the internal, self-timed Program SID operation, poll the BUSY

Security ID operation.

Lockout Security ID

The Lockout Security ID instruction prevents any future changes to the Security ID. To execute a Lock-

out SID, the host drives CE# low, sends the Lockout Security ID command cycle (85H), then drives

CE# high. A cycle is two nibbles long, most significant nibble first. The user map polls the BUSY bit in

Read-Status Register (RDSR)

The Read-Status register (RDSR) command outputs the contents of the Status register. The Status register

may be read at any time even during a Write operation. When a Write is in progress, check the BUSY bit

before sending any new commands to assure that the new commands are properly received by the device.

To execute a Read-Status-Register operation the host drives CE# low, then sends the Read-Status-

Register command cycle (05H). Each cycle is two nibbles long, most significant nibble first. Immedi-

ately after the command cycle, the device outputs data on the falling edge of the SCK signal. The data

output stream continues until terminated by a low-to-high transition on CE#. See Figure 20 for the

RDSR instruction sequence.

Figure 20:Read-Status-Register (RDSR) Sequence

Table 7: Program Security ID

Program Security ID

Address Range

Pre-Programmed at factory

00H – 07H

User Programmable

08H – 1FH

T7.0

1409

1409 F11.0

MODE 3

0

SCK

SIO(3:0)

CE#

C1 C0

MODE 0

2

H0 L0

MSN LSN

4

H0 L0

6

H0 L0

8N

H0 L0

Status Byte Status Byte Status Byte

Status Byte

Note: MSN = Most Significant Nibble; LSN = Least Significant Nibble

C[1:0] = 05H