S29WS064N0LBAI011 datasheet(46/99 Pages) SPANSION

46 / 99 page

S29WS-N_00_G0 January 25, 2005

Adva nce

Information

DQ6: Toggle Bit I .

Toggle Bit I on DQ6 indicates whether an Embedded Program or Erase algo-

rithm is in progress or complete, or whether the device has entered the Erase Suspend mode.

Toggle Bit I may be read at any address in the same bank, and is valid after the rising edge of

the final WE# pulse in the command sequence (prior to the program or erase operation), and dur-

ing the sector erase time-out.

During an Embedded Program or Erase algorithm operation, successive read cycles to any ad-

dress cause DQ6 to toggle. When the operation is complete, DQ6 stops toggling.

After an erase command sequence is written, if all sectors selected for erasing are protected, DQ6

toggles for approximately tASP [all sectors protected toggle time], then returns to reading array

data. If not all selected sectors are protected, the Embedded Erase algorithm erases the unpro-

tected sectors, and ignores the selected sectors that are protected.

The system can use DQ6 and DQ2 together to determine 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 tog-

gling. 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 tPAP 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 Embed-

ded Program Algorithm is complete.

See the following for additional information: Figure 7.6, Write Operation Status Flowchart; Figure

11.18, Toggle Bit Timings (During Embedded Algorithm), and Tables 7.23 and 7.24.

Toggle Bit I on DQ6 requires either OE# or CE# to be de-asserted and reasserted to show the

change in state.

DQ2: Toggle Bit II .

The “Toggle Bit II” on DQ2, when used with DQ6, indicates whether a par-

ticular sector is actively erasing (that is, the Embedded Erase algorithm is in progress), or whether

that sector is erase-suspended. Toggle Bit II is valid after the rising edge of the final WE# pulse

in the command sequence. DQ2 toggles when the system reads at addresses within those sectors

that have been selected for erasure. But DQ2 cannot distinguish whether the sector is actively

erasing or is erase-suspended. DQ6, by comparison, indicates whether the device is actively eras-

ing, or is in Erase Suspend, but cannot distinguish which sectors are selected for erasure. Thus,

both status bits are required for sector and mode information. Refer to Table 7.23 to compare

outputs for DQ2 and DQ6. See the following for additional information: Figure 7.6, the “DQ6: Tog-

gle Bit I” section, and Figures 11.17–11.20.

S29WS064N0LBAI011 Datasheet(PDF) 46 Page - SPANSION