m29dw256g Numonyx, m29dw256g Datasheet - Page 41

• Manufacturer Part Number: m29dw256g
• Description: 256-mbit X16, Multiple Bank, Page, Dual Boot 3 V Supply Flash Memory
• Manufacturer: Numonyx

6.4.3
6.4.4
Volatile protection mode command set
Enter Volatile Protection Command Set command
Three bus write cycles are required to issue the Enter Volatile Protection Command Set
command. Once the command has been issued, only the commands related to the volatile
protection mode and the Exit Protection Command Set can be issued to the device.
Volatile Protection Bit Program command (VPB Program)
The VPB Program command individually sets a VPB to ‘0’ for a given block.
If the NVPB for the same block is set, the block is locked regardless of the value of the VPB
bit. (see
Read VPB Status command
The status of a VPB for a given block can be read by issuing a Read VPB Status command
along with the block address.
VPB Clear command
The VPB Clear command individually clears (sets to ‘1’) the VPB for a given block.
If the NVPB for the same block is set, the block is locked regardless of the value of the VPB
bit (see
Non-volatile protection mode command set
Enter Non-volatile Protection Command Set command
Three bus write cycles are required to issue the Enter Non-volatile Protection Command Set
command. Once the command has been issued, only the commands related to the non-
volatile protection mode and the Exit Protection Command Set can be issued to the device.
Non-volatile Protection Bit Program command (NVPB Program)
A block can be protected from program or erase by issuing a Non-volatile Protection Bit
command along with the block address. This command sets the NVPB to ‘0’ for a given
block.
The Non-volatile Bit Program command is a special kind of Program command and must be
used according to all the Program command timings. The result from this command can be
verified by checking the status register.
Read Non-volatile Protection Bit Status command (Read NVPB Status)
The status of a NVPB for a given block or group of blocks can be read by issuing a Read
Non-Volatile Modify Protection Bit command along with the block address.
Clear all Non-volatile Protection Bits command (Clear all NVPBs)
The NVPBs are erased simultaneously by issuing a Clear all Non-volatile Protection Bits
command. No specific block address is required. If the NVPB lock bit is set to ‘0’, the
command fails.
Table 9: Block protection
Table 9: Block protection
status).
status).
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