Document Number: 002-00833 Rev. *L
Page 29 of 74
S29VS256R
S29VS128R
S29XS256R
S29XS128R
7.4
Blank Check
The Blank Check command will confirm if the selected sector is erased.
The Blank Check command does not allow for reads to the array during the Blank Check. Reads to the array while this command is
executing will return unknown data.
Blank Check is only functional in Asynchronous Read mode (Configuration Register - CR [15] = 1).
To initiate a Blank Check on Sector X, write 33h to address 555h in Sector X. while the device is in the Idle state (not during
program suspend, not during erase suspend, ...).
The Blank Check command may not be written while the device is actively programming or erasing. Blank Check does not
support simultaneous operations.
Use the Status Register read to confirm if the device is still busy and when compete if the sector is blank or not.
Bit 5 of the Status Register will be cleared to zero if the sector is erased and set to one if not erased.
Bit 7 & Bit 0 of the Status Register will show if the device is performing a Blank Check (similar to an erase operation).
As soon as any bit is found to not be erased, the device will halt the operation and report the results.
Once the Blank Check is completed, the device will to return to the Idle State.
7.5
Simultaneous Read/Write
The simultaneous read/write feature allows the host system to read data from one bank of memory while programming or erasing
another bank of memory. An erase operation may also be suspended to read from or program another location within the same bank
(note: programming to the sector being erased is not allowed).
Figure 20, Back-to-Back Read/Write Cycle Timings - ADM Interface
shows how read and write cycles may be initiated for simultaneous operation with zero latency. Refer to the
table for read-while-program and read-while-erase current specification.
