Rainbow Electronics W29C020C - Manual (Page 8)

W29C020C
- 8 -
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 DATA ADDRESS DATA
0 Write 5555 AA 5555H AAH 5555H AAH
1 Write 2AAA 55 2AAAH 55H 2AAAH 55H
2 Write 5555 90 5555H 80H 5555H F0H
3 Write - - 5555H AAH - -
4 Write - - 2AAAH 55H - -
5 Write - - 5555H 60H - -
Pause 10 µ S Pause 10 µ S Pause 10 µ S
Software Product Identification and Boot Block Lockout Detection Acquisition Flow
Product
Identification
Entry (1)
Load data AA
to
address 5555
Load data 55
to
address 2AAA
Load data 80
to
address 5555
Load data AA
to
address 5555
Load data 55
to
address 2AAA
Load data 60
to
address 5555
Product
Identification
and Boot Block
Lockout Detection
Mode (3)
Read address = 00000
data = DA
Read address = 00001
data = 45
Read address = 00002
data = FF/FE
(4)
Read address = 3FFF2
data = FF/FE
(5)
Product
Identification
Exit (1)
Load data AA
to
address 5555
Load data 55
to
address 2AAA
Load data F0
to
address 5555
Pause 10 S
Normal Mode
(6)
(2)
(2)
Pause 10 S
µ
µ
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.