D a t a S h e e t
edge is active for all synchronous accesses. Address bit A17 determines this set-
ting; “1” for rising active, “0” for falling active.
RDY Configuration
By default, the device is set so that the RDY pin will output VOH whenever there
is valid data on the outputs. The device can be set so that RDY goes active one
data cycle before active data. Address bit A18 determines this setting; “1” for
RDY active with data, “0” for RDY active one clock cycle before valid data.
Configuration Register
Table 12 shows the address bits that determine the configuration register settings
for various device functions.
Table 12. Burst Mode Configuration Register
Address Bit
Function
Settings (Binary)
0 = Synchronous Read (Burst Mode) Enabled
1 = Asynchronous Mode (default)
A19
Set Device Read Mode
0 = RDY active one clock cycle before data
1 = RDY active with data (default)
A18
RDY
0 = Burst starts and data is output on the falling edge of CLK
1 = Burst starts and data is output on the rising edge of CLK (default)
A17
A16
Clock
00 = Continuous (default)
01 = 8-word linear with wrap around
10 = 16-word linear with wrap around
11 = 32-word linear with wrap around
Burst Read Mode
A15
A14
A13
000 = Data is valid on the 2nd active CLK edge after AVD# transition to VIH
001 = Data is valid on the 3rd active CLK edge after AVD# transition to VIH
010 = Data is valid on the 4th active CLK edge after AVD# transition to VIH
011 = Data is valid on the 5th active CLK edge after AVD# transition to VIH
100 = Data is valid on the 6th active CLK edge after AVD# transition to VIH
101 = Data is valid on the 7th active CLK edge after AVD# transition to VIH (default)
Programmable
Wait State
A12
Note: Device will be in the default state upon power-up or hardware reset.
Sector Lock/Unlock Command Sequence
The sector lock/unlock command sequence allows the system to determine which
sectors are protected from accidental writes. When the device is first powered up,
all sectors are locked. To unlock a sector, the system must write the sector lock/
unlock command sequence. In the first and second cycles, the address must point
to the bank that contains the sector(s) to be locked or unlocked. The first and
second cycle data is 60h. In the third cycle, the address must point to the target
sector, and A6 is used to specify a lock (A6 = VIL) or unlock (A6 = VIH) operation.
The third cycle data is 60h. After the third cycle, the system can continue to lock
or unlock additional sectors in the same bank or exit the sector lock/unlock se-
quence by writing the reset command (F0h).
It is not possible to read from the bank selected for sector lock/unlock operations.
To enable such read operations, write the reset command.
Note that the last two outermost boot sectors can be locked by taking the WP#
signal to VIL.
May 15, 2007 27243B2
Am29BDS320G
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SPANSION [ SPANSION ]
