©2011 Silicon Storage Technology, Inc. S725081A 10/11
7
1 Mbit SPI Serial Flash
SST25VF010A
Data Sheet
Microchip Technology Company
Status Register
The software status register provides status on whether the flash memory array is available for any
Read or Write operation, whether the device is Write enabled, and the state of the memory Write pro-
tection. During an internal Erase or Program operation, the status register may be read only to deter-
mine the completion of an operation in progress. Table 4 describes the function of each bit in the
software status register.
Busy
The Busy bit determines whether there is an internal Erase or Program operation in progress. A “1” for
the Busy bit indicates the device is busy with an operation in progress. A “0” indicates the device is
ready for the next valid operation.
Write Enable Latch (WEL)
The Write-Enable-Latch bit indicates the status of the internal memory Write Enable Latch. If the
Write-Enable-Latch bit is set to “1”, it indicates the device is Write enabled. If the bit is set to “0” (reset),
it indicates the device is not Write enabled and does not accept any memory Write (Program/Erase)
commands. The Write-Enable-Latch bit is automatically reset under the following conditions:
• Power-up
• Write-Disable (WRDI) instruction completion
• Byte-Program instruction completion
• Auto Address Increment (AAI) programming reached its highest memory address
• Sector-Erase instruction completion
• Block-Erase instruction completion
• Chip-Erase instruction completion
Table 4: Software Status Register
Bit Name Function
Default at
Power-up Read/Write
0 BUSY 1 = Internal Write operation is in progress
0 = No internal Write operation is in progress
0R
1 WEL 1 = Device is memory Write enabled
0 = Device is not memory Write enabled
0R
2 BP0 Indicate current level of block write protection (See Table 5) 1 R/W
3 BP1 Indicate current level of block write protection (See Table 5) 1 R/W
4:5 RES Reserved for future use 0 N/A
6 AAI Auto Address Increment Programming status
1 = AAI programming mode
0 = Byte-Program mode
0R
7 BPL 1 = BP1, BP0 are read-only bits
0 = BP1, BP0 are read/writable
0 R/W
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