w49f002u Winbond Electronics Corp America, w49f002u Datasheet - Page 10

• Manufacturer Part Number: w49f002u
• Description: 256k X 8 Cmos Flash Memory
• Manufacturer: Winbond Electronics Corp America

Command Codes for Product Identification and Boot Block Lockout Detection
Software Product Identification and Boot Block Lockout Detection Acquisition Flow
Notes for software product identification/boot block lockout detection:
(1) Data Format: DQ7 DQ0 (Hex); Address Format: A14 A0 (Hex)
(2) A1 A17 = V
(3) The device does not remain in identification and boot block lockout detection mode if power down.
(4) If the output data in DQ0= " 1 " the boot block programming lockout feature is activated; if the output data in DQ0 = " 0 ,"
(5) The device returns to standard operation mode.
(6) Optional 1-byte cycle (write F0 hex at XXXX address) can be used to exit the product identification/boot block lockout
SEQUENCE
the lockout feature is inactivated and the boot block can be programmed.
detection.
1 Write
2 Write
3 Write
BYTE
IL
; manufacture code is read for A0 = V
Entry (1)
Identification
Product
address 5555
address 5555
address 2AAA
Pause 10 S
Load data AA
Load data 55
Load data 90
IDENTIFICATION/BOOT BLOCK
ADDRESS
LOCKOUT DETECTION ENTRY
to
to
to
2AAA
5555
5555
SOFTWARE PRODUCT
Pause 10 S
Mode (3)
Identification
and Boot Block
Lockout Detection
Product
Read address = 0001
Read address = 0002
data =in DQ0= "1" / "0"
Read address = 0000
IL
data = DA
; device code is read for A0 = V
DATA
AA
55
90
- 10 -
(4)
(2)
(2)
ADDRESS
Product
Identification Exit(6)
IDENTIFICATION/BOOT BLOCK
LOCKOUT DETECTION EXIT(6)
2AAAH
5555H
5555H
IH
SOFTWARE PRODUCT
.
Normal Mode
address 5555
Load data 55
address 2AAA
Load data F0
Pause 10 S
to
to
W49F002U
(5)
DATA
AAH
55H
F0H