M36DR432AD Datasheet, PDF (48/52 Pages) STMicroelectronics – 32 Mbit 2Mb x16, Dual Bank, Page Flash Memory and 4 Mbit 256Kb x16 SRAM, Multiple Memory Product

M36DR432AD, M36DR432BD
APPENDIX B. COMMON FLASH INTERFACE
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 Read CFI Query Command is issued
the device enters CFI Query mode and the data
structure is read from the memory. Tables 32, 33,
34 and 35 show the address used to retrieve each
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 contains also a security
area starting at address 81h. This area can be ac-
cessed only in read mode and it is impossible to
change after it has been written by ST. Issue a
Read command to return to Read mode.
Table 32. Query Structure Overview
Offset
Sub-section Name
00h Reserved
10h CFI Query Identification String
1Bh System Interface Information
27h Device Geometry Definition
P
Primary Algorithm-specific Extended Query table
A
Alternate Algorithm-specific Extended Query table
Description
Reserved for algorithm-specific information
Command set ID and algorithm data offset
Device timing & voltage information
Flash device layout
Additional information specific to the Primary
Algorithm (optional)
Additional information specific to the Alternate
Algorithm (optional)
Table 33. CFI Query Identification String
Offset
Data
Description
00h
0020h
Manufacturer Code
01h
00A1h - bottom
00A0h - top
Device Code
02h-0Fh
reserved
Reserved
10h
0051h
Query Unique ASCII String "QRY"
11h
0052h
Query Unique ASCII String "QRY"
12h
0059h
Query Unique ASCII String "QRY"
13h
0002h
Primary Algorithm Command Set and Control Interface ID code 16 bit ID code
14h
0000h
defining a specific algorithm
15h
offset = P = 0040h
Address for Primary Algorithm extended Query table
16h
0000h
17h
0000h
Alternate Vendor Command Set and Control Interface ID Code second vendor
18h
0000h
- specified algorithm supported (note: 0000h means none exists)
19h
value = A = 0000h _{Address for Alternate Algorithm extended Query table}
1Ah
0000h
note: 0000h means none exists
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