X76F101 Datasheet, PDF (4/17 Pages) Xicor Inc. – Secure SerialFlash

X76F101
Figure 2. Data Validity
SCL
SDA
Data Stable
Data
Change
Figure 3. Definition of Start and Stop Conditions
SCL
SDA
Start Condition
Stop Condition
Table 1. X76F101 Instruction Set
Command
after Start
Command Description
Password
used
1 0 0 S₃ S₂ S₁ S₀0
1 0 0 S₃ S₂ S₁ S₀ 1
11111100
11111110
01010101
Sector Write
Sector Read
Change Write Password
Change Read Password
Password ACK Command
Write
Read
Write
Write
None
Illegal command codes will be disregarded. The part will respond with a “no-ACK” to the illegal byte and then return to
the standby mode. All write/read operations require a password.
PROGRAM OPERATIONS
Sector Write
The sector write mode requires issuing the 8-bit write
command followed by the password and then the data
bytes transferred as illustrated in figure 4. The write
command byte contains the address of the sector to be
written. Data is written starting at the first address of a
sector and eight bytes must be transferred. After the last
byte to be transferred is acknowledged a stop condition is
issued which starts the nonvolatile write cycle. If more or
less than 8 bytes are transferred, the data in the sector
remains unchanged.
ACK Polling
Once a stop condition is issued to indicate the end of the
host’s write sequence, the X76F101 initiates the internal
nonvolatile write cycle. In order to take advantage of the
typical 5ms write cycle, ACK polling can begin
immediately. This involves issuing the start condition
4