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Am29LV642D
25022A2 May 5, 2006
D A T A S H E E T
Command Definitions
Table 10. Am29LV642D Command Definitions
Legend:
X = Don’t care
RA = Address of the memory location to be read.
RD = Data read from location RA during read operation.
PA = Address of the memory location to be programmed. Addresses
latch on the falling edge of the WE# or CE# (or CE2#) pulse, whichever
happens later.
PD = Data to be programmed at location PA. Data latches on the rising
edge of WE# or CE# (or CE2#) pulse, whichever happens first.
SA = Address of the sector to be verified (in autoselect mode) or
erased. Address bits A21–A15 uniquely select any sector.
Notes:
1.
2.
3.
See Table 1 for description of bus operations.
All values are in hexadecimal.
Except for the read cycle and the fourth cycle of the autoselect
command sequence, all bus cycles are write cycles.
Data bits DQ15–DQ8 are don’t care in command sequences,
except for RD and PD.
Unless otherwise noted, address bits A21–A15 are don’t cares.
No unlock or command cycles required when device is in read
mode.
The Reset command is required to return to the read mode (or to
the erase-suspend-read mode if previously in Erase Suspend)
when the device is in the autoselect mode, or if DQ5 goes high
(while the device is providing status information).
The fourth cycle of the autoselect command sequence is a read
cycle. See the Autoselect Command Sequence section for more
information.
4.
5.
6.
7.
8.
9.
The data is 00h for an unprotected sector group and 01h for a
protected sector group.
10. The Unlock Bypass command is required prior to the Unlock
Bypass Program command.
11. The Unlock Bypass Reset command is required to return to the
read mode when the device is in the unlock bypass mode.
12. The system may read and program in non-erasing sectors, or
enter the autoselect mode, when in the Erase Suspend mode.
The Erase Suspend command is valid only during a sector erase
operation.
13. The Erase Resume command is valid only during the Erase
Suspend mode.
14. Command is valid when device is ready to read array data or when
device is in autoselect mode.
Command
Sequence
(Note 1)
C
Bus Cycles (Notes 2–5)
Third
Addr
Data
First
Second
Addr
Fourth
Fifth
Sixth
Addr
RA
XXX
555
555
Data
RD
F0
AA
AA
Data
Addr
Data
Addr
Data
Addr
Data
Read (Note 6)
Reset (Note 7)
Manufacturer ID
Device ID
1
1
4
4
A
Enter SecSi Sector Region
Exit SecSi Sector Region
Program
Unlock Bypass
2AA
2AA
55
55
555
555
90
90
X00
X01
0001
22D7
Sector Group Protect Verify
(Note 9)
4
555
AA
2AA
55
555
90
(SA)X02
XX00/
XX01
3
4
4
3
2
2
6
6
1
1
1
555
555
555
555
AA
AA
AA
AA
2AA
2AA
2AA
2AA
55
55
55
55
555
555
555
555
88
90
A0
20
XXX
PA
00
PD
Unlock Bypass Program (Note 10)
XXX
A0
PA
PD
Unlock Bypass Reset (Note 11)
Chip Erase
Sector Erase
Erase Suspend (Note 12)
Erase Resume (Note 13)
CFI Query (Note 14)
XXX
555
555
BA
BA
55
90
AA
AA
B0
30
98
XXX
2AA
2AA
00
55
55
555
555
80
80
555
555
AA
AA
2AA
2AA
55
55
555
SA
10
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