am49pdl127ah Meet Spansion Inc., am49pdl127ah Datasheet - Page 55

• Manufacturer Part Number: am49pdl127ah
• Description: Stacked Multi-chip Package Mcp Flash Memory And Psram, 128 Megabit 8m ? 16-bit Cmos 3.0 Volt-only, Simultaneous Operation Flash Memory And 16 Mbit 1m ? 16-bit Cmos Pseudo Static Ram
• Manufacturer: Meet Spansion Inc.

RY/BY#: Ready/Busy#
The RY/BY# is a dedicated, open-drain output pin
which indicates whether an Embedded Algorithm is in
progress or complete. The RY/BY# status is valid after
the rising edge of the final WE# pulse in the command
sequence. Since RY/BY# is an open-drain output, sev-
eral RY/BY# pins can be tied together in parallel with a
pull-up resistor to V
If the output is low (Busy), the device is actively eras-
ing or programming. (This includes programming in
the Erase Suspend mode.) If the output is high
(Ready), the device is in the read mode, the standby
mode, or one of the banks is in the erase-suspend-
read mode.
Table 18 shows the outputs for RY/BY#.
DQ6: Toggle Bit I
Toggle Bit I on DQ6 indicates whether an Embedded
Program or Erase algorithm is in progress or com-
plete, or whether the device has entered the Erase
Suspend mode. Toggle Bit I may be read at any ad-
dress, and is valid after the rising edge of the final
WE# pulse in the command sequence (prior to the
program or erase operation), and during the sector
erase time-out.
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#f1 to control the read cycles. When the operation
is complete, DQ6 stops toggling.
After an erase command sequence is written, if all
sectors selected for erasing are protected, DQ6 tog-
gles for approximately 400 µs, then 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 pro-
tected.
The system can use DQ6 and DQ2 together to deter-
mine whether a sector is actively erasing or is erase-
suspended. When the device is actively erasing (that
is, the Embedded Erase algorithm is in progress), DQ6
toggles. When the device enters the Erase Suspend
mode, DQ6 stops toggling. However, the system must
also use DQ2 to determine which sectors are erasing
or erase-suspended. Alternatively, the system can use
DQ7 (see the subsection on DQ7: Data# Polling).
If a program address falls within a protected sector,
DQ6 toggles for approximately 1 µs after the program
command sequence is written, then returns to reading
array data.
DQ6 also toggles during the erase-suspend-program
mode, and stops toggling once the Embedded Pro-
gram algorithm is complete.
December 18, 2003
CC
.
A D V A N C E
Am49PDL127AH/Am49PDL129AH
I N F O R M A T I O N
Table 18 shows the outputs for Toggle Bit I on DQ6.
Figure 7 shows the toggle bit algorithm.
the
gle bit timing diagrams. Figure 22 shows the differ-
ences between DQ2 and DQ6 in graphical form. See
also the subsection on DQ2: Toggle Bit II.
Note: The system should recheck the toggle bit even if DQ5
= “1” because the toggle bit may stop toggling as DQ5
changes to “1.” See the subsections on DQ6 and DQ2 for
more information.
“Flash AC Characteristics”
No
Figure 7. Toggle Bit Algorithm
Read Byte Twice
Complete, Write
Reset Command
Program/Erase
Operation Not
Address =VA
Address =VA
Address = VA
(DQ7–DQ0)
(DQ7–DQ0)
(DQ7–DQ0)
Read Byte
Read Byte
Toggle Bit
Toggle Bit
DQ5 = 1?
= Toggle?
= Toggle?
START
Yes
Yes
Yes
section shows the tog-
Operation Complete
No
No
Program/Erase
Figure 21
53
in