D A T A S H E E T
Command Definitions
Table 5. Am29LV400B Command Definitions
Bus Cycles (Notes 2–5)
Command
Sequence
(Note 1)
First
Second
Third
Addr
Fourth
Data Addr Data
Fifth
Sixth
Addr Data Addr Data
Addr Data Addr Data
Read (Note 6)
Reset (Note 7)
1
1
RA
XXX
555
AAA
555
AAA
555
AAA
RD
F0
Word
2AA
555
2AA
555
2AA
555
555
AAA
555
Manufacturer ID
4
4
4
AA
AA
AA
55
55
55
90
90
90
X00
01
Byte
Word
Byte
Word
Byte
X01
X02
X01
X02
22B9
B9
Device ID,
Top Boot Block
AAA
555
22BA
BA
Device ID,
Bottom Boot Block
AAA
XX00
XX01
00
(SA)
X02
Word
Byte
555
2AA
555
555
Sector Protect Verify
(Note 9)
4
AA
55
90
(SA)
X04
AAA
AAA
01
Word
Byte
Word
Byte
555
AAA
555
AAA
XXX
XXX
555
2AA
555
2AA
555
PA
555
AAA
555
Program
Unlock Bypass
4
3
AA
AA
55
55
A0
20
PA
PD
AAA
Unlock Bypass Program (Note 10)
Unlock Bypass Reset (Note 11)
2
2
A0
90
PD
00
XXX
2AA
555
2AA
555
Word
555
AAA
555
555
AAA
555
2AA
555
2AA
555
555
Chip Erase
Byte
6
6
AA
AA
55
55
80
80
AA
AA
55
55
10
30
AAA
555
AAA
Word
Sector Erase
Byte
SA
AAA
XXX
XXX
AAA
AAA
Erase Suspend (Note 12)
Erase Resume (Note 13)
1
1
B0
30
Legend:
X = Don’t care
PD = Data to be programmed at location PA. Data latches on the
rising edge of WE# or CE# pulse, whichever happens first.
RA = Address of the memory location to be read.
SA = Address of the sector to be verified (in autoselect mode) or
erased. Address bits A17–A12 uniquely select any sector.
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# pulse,
whichever happens later.
Notes:
1. See Table 1 for description of bus operations.
2. All values are in hexadecimal.
8. The fourth cycle of the autoselect command sequence is a
read cycle.
3. Except when reading array or autoselect data, all bus cycles
are write operations.
9. The data is 00h for an unprotected sector and 01h for a
protected sector. See “Autoselect Command Sequence” for
more information.
4. Data bits DQ15–DQ8 are don’t cares for unlock and command
cycles.
10. The Unlock Bypass command is required prior to the Unlock
Bypass Program command.
5. Address bits A17–A11 are don’t cares for unlock and
command cycles, except when SA or PA required.
11. The Unlock Bypass Reset command is required to return to
reading array data when the device is in the unlock bypass
mode.
6. No unlock or command cycles required when reading array
data.
7. The Reset command is required to return to reading array data
when device is in the autoselect mode, or if DQ5 goes high
(while the device is providing status data).
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.
December 4, 2006 21523D4
Am29LV400B
19
SPANSION [ SPANSION ]
