FLASH
AS29F010
edge of the final WE\ pulse in the command sequence (prior
to the program or erase operation), and during the sector erase
time-out.
WRITE OPERATION STATUS
The device provides several bits to determine the status
of a write operation: DQ3, DQ5, DQ6, and DQ7. Table 5 and
the following subsections describe the functions of these bits.
DQ7 and DQ6 each offer a method for determining whether a
program or erase operation is complete or in progress. These
three bits are discussed first.
During an Embedded Program or Erase algorithm
op-
eration, successive read cycles to any address cause DQ6 to
toggle. (The system may use either OE\ or CE\ to control
the read cycles.) When the operation is complete, DQ6 stops
toggling.
After an erase command sequence is written, if all sec-
tors selected for erasing are protected, DQ6 toggles for
DQ7: Data\ Polling
The Data\ Polling bit, DQ7, indicates to the host system
whether an Embedded Algorithm is in progress or completed.
Data\ Polling is valid after the rising edge of the final WE\ pulse
in the program or erase command sequence.
FIGURE 3: DATA\ POLLING ALGORITHM
During the Embedded Program algorithm, the device out-
puts on DQ7 the complement of the datum programmed to DQ7.
When the Embedded Program algorithm is complete, the device
outputs the datum programmed to DQ7. The system must pro-
vide the program address to read valid status
on DQ7. If a program address falls within a
tor, Data\ Polling on DQ7 is active for
information
protected sec-
approximately
2μs, then the device returns to reading array data.
During the Embedded Erase algorithm, Data\ Polling
produces a “0” on DQ7. When the Embedded Erase algorithm
is complete, Data\ Polling produces a “1” on DQ7. This is
analogous to the complement/true datum output described for
the Embedded Program algorithm: the erase function changes
all the bits in a sector to “1”; prior to this, the device outputs
the “complement,” or “0”. The system must provide an
ad-
dress within any of the sectors selected for erasure to read valid
status information on DQ7.
After an erase command sequence is written, if all sec-
tors selected for erasing are protected, Data\ Polling on DQ7
is active for approximately 100μs, then the device returns to
reading array data. If not all selected sectors are protected, the
Embedded Erase algorithm erases the unprotected sectors, and
ignores the selected sectors that are protected.
When the system detects DQ7 has changed from the
complement to true data, it can read valid data at DQ7-DQ0
on the following read cycles. This is because DQ7 may change
asynchronously with DQ0-DQ6 while Output Enable (OE\) is
asserted low. The Data\ Polling Timings (During Embedded
Algorithms) figure in the “AC Characteristics” section
il-
lustrates this.
Table 5 shows the outputs for Data\ Polling on DQ7.
Figure 3 shows the Data\ Polling algorithm.
NOTE:
DQ6: Toggle Bit I
Toggle bit I on DQ6 indicates whether an Embedded
Program or Erase algorithm is in progress or complete. Toggle
1) VA = Valid address for programming. During a sector erase operation, a
valid address is an address within any sector selected for erasure. During chip
erase, a valid address is any non-protected sector address.
Bit I may be read at any address, and is valid after the rising 2) DQ7 should be rechecked even if DQ5 = “1” because DQ7 may change
simultaneously with DQ5.
AS29F010
Micross Components reserves the right to change products or specifications without notice.
Rev. 2.6 11/10
10
MICROSS [ MICROSS COMPONENTS ]
