X76F101 Datasheet, PDF (7/17 Pages) Xicor Inc. – Secure SerialFlash

X76F101
PASSWORDS
Passwords are changed by sending the "change read
password" or "change write password" commands in a
normal sector write operation. A full eight bytes
containing the new password must be sent, following
successful transmission of the current write password
and a valid password ACK response. The user can use a
repeated ACK Polling command to check that a new
password has been written correctly. An ACK indicates
that the new password is valid.
There is no way to read any of the passwords.
RESPONSE TO RESET (DEFAULT = 19 01 AA 55)
The ISO Response to reset is controlled by the RST, CS
and CLK pins. When RST is pulsed high, while CS is low,
the device will output 32 bits of data, one bit per clock.
Figure 7. Response to RESET (RST)
This conforms to the ISO standard for “synchronous
response to reset”. CS must remain LOW and the part
must not be in a write cycle for the response to reset to
occur.
After initiating a nonvolatile write cycle the RST pin must
not be pulsed until the nonvolatile write cycle is complete.
If not, the ISO response will not be activated. Also, any
attempt to pulse the RST pin in the middle of an ISO
transaction will stop the transaction with the SDA pin in
high impedance. The user will have to issue a stop
condition and start the transaction again. If at any time
during the Response to Reset CS goes HIGH, the
response to reset will be aborted and the part will return
to the standby state. A Response to Reset is not
available during a nonvolatile write cycle.
Continued clocks after the 32 bits, will output the 32 bit
sequence again, starting at byte 0.
CS
RST
SCK
SO
LSB
Byte
MSB LSB
0
MSB LSB
1
MSB LSB
2
MSB
3
ABSOLUTE MAXIMUM RATINGS*
Temperature under Bias ..................... –65°C to +135°C
Storage Temperature ..........................–65°C to +150°C
Voltage on any Pin with
Respect to V_SS .......................................–1V to +7V
D.C. Output Current..................................................5mA
Lead Temperature
(Soldering, 10 seconds).................................. 300°C
*COMMENT
Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only and the functional operation of
the device at these or any other conditions above those
listed in the operational sections of this specification is
not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device
reliability.
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