X76F640 Datasheet, PDF (4/17 Pages) Xicor Inc. – Secure SerialFlash

X76F640
Figure 2. Data Validity
SCL
SDA
Data Stable
Data
Change
Figure 3. Definition of Start and Stop Conditions
7025 FM 04
SCL
SDA
Start Condition
Stop Condition
7025 FM 05
Table 1. X76F640 Instruction Set
1st Byte
after Start
1000 0000
1000 1000
1001 0000
1001 1000
1010 0000
1010 1000
1011 0000
1011 1000
1100 0000
1110 0000
1110 1000
1111 0000
1st Byte
after
Password
High Address
High Address
High Address
High Address
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000
not used
not used
not used
All the rest
2nd Byte
after
Password
Low address
Low address
Low address
Low address
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000
not used
not used
not used
Command Description
Read (Array 0)
Read (Array 1)
Sector Write (Array 0)
Sector Write (Array 1)
Change Read 0 Password
Change Read 1 Password
Change Write 0 Password
Change Write 1 Password
Change Reset Password
Reset Password Command
Reset Device Command
ACK Polling command (Ends Password operation)
Reserved
Password
used
Read 0
Read 1
Write 0
Write 1
Read 0
Read 1
Write 0
Write 1
Reset
Reset
Reset
None
7025 FM T04
Notes:Illegal command codes will be disregarded. The part will respond with a “no-A CK” to the illegal byte and then return to the standby mode.
All write/read operations require a password.
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