MBM29LV160TE/BE-70/90/12
• DQ2
Toggle Bit II
This Toggle Bit II, along with DQ6, can be used to determine whether the device is in the Embedded Erase
Algorithm or in Erase Suspend.
Successive reads from the erasing sector will cause DQ2 to toggle during the Embedded Erase Algorithm. If the
device is in the erase-suspended-read mode, successive reads from the erase-suspended sector will cause
DQ2 to toggle. When the device is in the erase-suspended-program mode, successive reads from the byte
address of the non-erase suspended sector will indicate a logic “1” at DQ2.
DQ6 is different from DQ2 in that DQ6 toggles only when the standard program or Erase, or Erase Suspend
Program operation is in progress.
For example, DQ2 and DQ6 can be used together to determine if the erase-suspend-read mode is in progress.
(DQ2 toggles while DQ6 does not.) See also Table 9 and Figure 11.
Furthermore, DQ2 can also be used to determine which sector is being erased. When the device is in the erase
mode, DQ2 toggles if this bit is read from an erasing sector.
Table 9 Toggle Bit Status
Mode
DQ7
DQ7
0
DQ6
DQ2
1
Program
Erase
Toggle
Toggle
Toggle
Erase Suspend Read
(Erase Suspended Sector)
(Note 1)
1
1
Toggle
Erase-Suspend Program
DQ7
Toggle (Note 1)
1 (Note 2)
Notes: 1. Performing successive read operations from any address will cause DQ6 to toggle.
2. Reading the byte address being programmed while in the erase-suspend program mode will indicate
logic “1” at the DQ2 bit. However, successive reads from the erase-suspended sector will cause DQ2 to
toggle.
• RY/BY
Ready/Busy Pin
The MBM29LV160TE/BE provides a RY/BY open-drain output pin as a way to indicate to the host system that
the Embedded Algorithms are either in progress or has been completed. If the output is low, the device is busy
with either a program or erase operation. If the output is high, the device is ready to accept any read/write or
erase operation. When the RY/BY pin is low, the devices will not accept any additional program or erase com-
mands with the exception of the Erase Suspend command. If the MBM29LV160TE/BE is placed in an Erase
Suspend mode, the RY/BY output will be high, by means of connecting with a pull-up resister to VCC.
During programming, the RY/BY pin is driven low after the rising edge of the fourth WE pulse. During an erase
operation, the RY/BY pin is driven low after the rising edge of the sixth WE pulse. The RY/BY pin will indicate a
busy condition during the RESET pulse. See Figures 12 and 13 for a detailed timing diagram. The RY/BY pin
is pulled high in standby mode.
Since this is an open-drain output, RY/BY pins can be tied together in parallel with a pull-up resistor to VCC.
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