W29C040
Command Codes for Product Identification and Boot Block Lockout Detection
BYTE
SEQUENCE
ALTERNATE PRODUCT (7)
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION ENTRY
SOFTWARE PRODUCT
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION ENTRY
SOFTWARE PRODUCT
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION EXIT
ADDRESS
DATA
ADDRESS
5555H
DATA
AAH
55H
ADDRESS
DATA
0 Write
1 Write
2 Write
3 Write
4 Write
5 Write
5555
AA
55
90
-
5555H
AAH
2AAA
2AAAH
5555H
2AAAH
55H
5555
80H
5555H
F0H
-
-
-
5555H
AAH
55H
-
-
-
-
-
-
-
2AAAH
5555H
-
60H
Pause 10 mS
Pause 10 mS
Pause 10 mS
Software Product Identification and Boot Block Lockout Detection Acquisition Flow
Product
Product
Product
Identification
Exit (1)
Identification
Entry (1)
Identification
and Boot Block
Lockout Detection
Mode (3)
Load data AA
to
address 5555
(2)
(2)
(4)
(5)
Load data AA
Load data 55
to
Read address = 00000
data = DA
to
address 5555
address 2AAA
Load data 80
to
address 5555
Load data 55
to
address 2AAA
Read address = 00001
data = 46
Load data AA
to
address 5555
Load data F0
to
address 5555
Read address = 00002
data = FF/FE
Load data 55
to
address 2AAA
Read address = 7FFF2
data = FF/FE
Pause 10 uS
Normal Mode
(6)
Load data 60
to
address 5555
Pause 10 uS
Notes for software product identification/boot block lockout detection:
(1) Data Format: DQ7- DQ0 (Hex); Address Format: A14- A0 (Hex)
(2) A1- A18 = VIL; manufacture code is read for A0 = VIL; device code is read for A0 = VIH.
(3) The device does not remain in identification and boot block (address 0002 Hex/7FFF2 Hex respond to first 16K/last 16K) lockout detection
mode if power down.
(4), (5) If the output data is "FF Hex," the boot block programming lockout feature is activated; if the output data "FE Hex," the lockout feature is
inactivated and the block can be programmed.
(6) The device returns to standard operation mode.
(7) This product supports both the JEDEC standard 3 byte command code sequence and original 6 byte command code sequence. For new
designs, Winbond recommends that the 3 byte command code sequence be used.
- 8 -
WINBOND [ WINBOND ]
