W29C020C
Command Codes for Product Identification and Boot Block Lockout Detection
BYTE
SEQUENCE
ALTERNATE PRODUCT (7)
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION ENTRY
ADDRESS
0 Write
1 Write
2 Write
3 Write
4 Write
5 Write
5555
2AAA
5555
-
-
-
Pause 10
µS
DATA
AA
55
90
-
-
-
SOFTWARE PRODUCT
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION ENTRY
ADDRESS
5555H
2AAAH
5555H
5555H
2AAAH
5555H
Pause 10
µ
S
DATA
AAH
55H
80H
AAH
55H
60H
SOFTWARE PRODUCT
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION EXIT
ADDRESS
5555H
2AAAH
5555H
-
-
-
Pause 10
µ
S
DATA
AAH
55H
F0H
-
-
-
Software Product Identification and Boot Block Lockout Detection Acquisition Flow
Product
Identification
Entry (1)
Load data AA
to
address 5555
(2)
Read address = 00000
data = DA
Product
Identification
and Boot Block
Lockout Detection
Mode (3)
Product
Identification
Exit (1)
Load data 55
to
address 2AAA
Load data AA
to
address 5555
Load data 80
to
address 5555
(2)
Read address = 00001
data = 45
Load data 55
to
address 2AAA
Load data AA
to
address 5555
(4)
Read address = 00002
data = FF/FE
Load data F0
to
address 5555
Load data 55
to
address 2AAA
(5)
Read address = 3FFF2
data = FF/FE
Pause 10
µ
S
Load data 60
to
address 5555
(6)
Normal Mode
Pause 10
µ
S
Notes for software product identification/boot block lockout detection:
(1) Data Format: DQ7−DQ0 (Hex); Address Format: A14−A0 (Hex)
(2) A1−A16 = V
IL
; manufacture code is read for A0 = V
IL
; device code is read for A0 = V
IH
.
(3) The device does not remain in identification and boot block (address 0002 Hex/3FFF2 Hex respond to first 8K/last 8K) 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 ]
