M29W641DL70N6T View Datasheet(PDF) - STMicroelectronics

Part Name

Description

Manufacturer

M29W641DL70N6T

64 Mbit (4Mb x16, Uniform Block) 3V Supply Flash Memory

STMicroelectronics 

M29W641DH, M29W641DL, M29W641DU

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.

When the CFI Query Command is issued the de-

vice enters CFI Query mode and the data structure

is read from the memory. Table 18 to Table 23

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 23, 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 ST.

Table 18. Query Structure Overview

Address

Sub-section Name

10h

CFI Query Identification String

1Bh

System Interface Information

27h

Device Geometry Definition

40h

Primary Algorithm-specific Extended

Query table

61h

Security Code Area

Note: Query data are always presented on the lowest order data outputs.

Description

Command set ID and algorithm data offset

Device timing & voltage information

Flash device layout

Additional information specific to the Primary

Algorithm (optional)

64 bit unique device number

Table 19. CFI Query Identification String

Address

Data

Description

Value

10h

0051h

“Q”

11h

0052h Query Unique ASCII String "QRY"

"R"

12h

0059h

"Y"

13h

0002h Primary Algorithm Command Set and Control Interface ID code 16 bit

AMD

14h

0000h ID code defining a specific algorithm

Compatible

15h

0040h

Address for Primary Algorithm extended Query table (see Table 22)

P = 40h

16h

0000h

17h

18h

0000h

0000h

Alternate Vendor Command Set and Control Interface ID Code second

vendor - specified algorithm supported

NA

19h

0000h Address for Alternate Algorithm extended Query table

NA

1Ah

0000h

Note: Query data are always presented on the lowest order data outputs (DQ7-DQ0) only. DQ8-DQ15 are ‘0’.

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