6.4.1 Block Write-Protect Function
The
WRSR instruction allows the user to configure one of four possible memory
array write-protection modes by setting the Block Write-Protect bits (BP1, BP0). The
available protection levels are:- No protection applied to the memory array
- The upper quarter (¼) of the address range is write-protected, making the highest address range read-only
- The upper half (½) of the address range is write-protected, making the highest address range read-only
- The entire memory array is write-protected, making all addresses read-only
The Block Write-Protect levels and their corresponding STATUS register control bits are
listed in Table 6-4.
| Level | STATUS Register Bits | Write-Protected/Read‑Only Address Range | ||
|---|---|---|---|---|
| BP1 | BP0 | AT25080B | AT25160B | |
| 0 | 0 | 0 | None | None |
| 1 (1/4) | 0 | 1 | 0300h-03FFh | 0600h-07FFh |
| 2 (1/2) | 1 | 0 | 0200h-03FFh | 0400h-07FFh |
| 3 (All) | 1 | 1 | 0000h-03FFh | 0000h-07FFh |