M29W160ET, M29W160EB
APPENDIX B. COMMON FLASH INTERFACE (CFI)
The Common Flash Interface is a JEDEC ap-
proved, 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 mem-
ory. The system can interface easily with the de-
vice, enabling the software to upgrade itself when
necessary.
and 26 show the addresses used to retrieve the
data.
The CFI data structure also contains a security
area where a 64 bit unique security number is writ-
ten (see Table 26, Security Code area). This area
can be accessed only in Read mode by the final
user. It is impossible to change the security num-
ber after it has been written by Numonyx. Issue a
Read command to return to Read mode.
When the CFI Query Command is issued the de-
vice enters CFI Query mode and the data structure
is read from the memory. Tables 21, 22, 23, 24, 25
Note: The Common Flash Interface is only avail-
able for Temperature range 6 (–40 to 85°C).
Table 21. Query Structure Overview
Address
Sub-section Name
Description
x16
10h
1Bh
27h
x8
20h
36h
4Eh
CFI Query Identification String
System Interface Information
Device Geometry Definition
Command set ID and algorithm data offset
Device timing & voltage information
Flash device layout
Primary Algorithm-specific Extended
Query table
Additional information specific to the Primary
Algorithm (optional)
40h
80h
61h
C2h
Security Code Area
64 bit unique device number
Note: Query data are always presented on the lowest order data outputs.
Table 22. CFI Query Identification String
Address
Data
Description
Value
x16
10h
11h
12h
13h
14h
15h
16h
17h
18h
19h
1Ah
x8
20h
22h
24h
26h
28h
2Ah
2Ch
2Eh
30h
32h
34h
0051h
0052h
0059h
0002h
0000h
0040h
0000h
0000h
0000h
0000h
0000h
"Q"
"R"
"Y"
Query Unique ASCII String "QRY"
Primary Algorithm Command Set and Control Interface ID code 16 bit
ID code defining a specific algorithm
AMD
Compatible
Address for Primary Algorithm extended Query table (see Table 24)
P = 40h
NA
Alternate Vendor Command Set and Control Interface ID Code second
vendor - specified algorithm supported
Address for Alternate Algorithm extended Query table
NA
Note: Query data are always presented on the lowest order data outputs (DQ7-DQ0) only. DQ8-DQ15 are ‘0’.
30/40
NUMONYX [ NUMONYX B.V ]
