m58lt256jsb STMicroelectronics, m58lt256jsb Datasheet - Page 78

• Manufacturer Part Number: m58lt256jsb
• Description: 256 Mbit 16 Mb 16, Multiple Bank, Multilevel, Burst 1.8 V Supply, Secure Flash Memories
• Manufacturer: STMicroelectronics

Common Flash interface
Appendix B
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The CFI (common Flash interface) is a JEDEC approved, standardized data structure that
can be read from the Flash memory device. It allows a system software to query the device
to determine various electrical and timing parameters, density information, and functions
supported by the memory. The system can interface easily with the device, enabling the
software to upgrade itself when necessary.
When the Read CFI Query command is issued the device enters CFI query mode and the
data structure is read from the memory. Tables 35, 36, 37, 38, 39, 40, 41, 42,
show the addresses used to retrieve the data. The query data is always presented on the
lowest order data outputs (DQ0-DQ7), the other outputs (DQ8-DQ15) are set to 0.
The CFI data structure also contains a security area where a 64-bit unique security number
is written (see
in read mode by the final user. It is impossible to change the security number after it has
been written by ST. Issue a Read Array command to return to read mode.
Table 35.
1. The Flash memory display the CFI data structure when CFI Query command is issued. In this table are
Offset
01Bh
000h
010h
027h
080h
listed the main sub-sections detailed in Tables 36, 37,
lowest order data outputs.
P
A
Reserved
CFI query identification string
System interface information
Device geometry definition
Primary algorithm-specific extended
query table
Alternate algorithm-specific extended
query table
Security code area
Common Flash interface
Query structure overview
Figure 4: Protection Register memory
Sub-section name
38
Reserved for algorithm-specific information
Command set ID and algorithm data offset
Device timing and voltage information
Flash device layout
Additional information specific to the primary
algorithm (optional)
Additional information specific to the alternate
algorithm (optional)
Lock Protection Register
Unique device number and
User programmable OTP
and 39. Query data is always presented on the
map). This area can only be accessed
M58LT256JST, M58LT256JSB
Description
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and
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