M58LW032 STMICROELECTRONICS [STMicroelectronics], M58LW032 Datasheet - Page 22

• Manufacturer Part Number: M58LW032
• Description: 32 Mbit 2Mb x16, Uniform Block, Burst 3V Supply Flash Memory
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

M58LW032A
Two Bus Write cycles are required to issue the Set
Burst Configuration Register command. Once the
command is issued the memory returns to Read
mode as if a Read Memory Array command had
been issued.
The value for the Burst Configuration Register is
presented on A1-A16. M0 is on A1, M1 on A2, etc.;
the other address bits are ignored.
Block Protect Command. The
command is used to protect a block and prevent
Program or Erase operations from changing the
data in it. Two Bus Write cycles are required to is-
sue the Block Protect command; the second Bus
Write cycle latches the block address in the inter-
nal state machine and starts the Program/Erase
Controller. Once the command is issued subse-
quent Bus Read operations read the Status Reg-
ister. See the section on the Status Register for
details on the definitions of the Status Register
bits. Typical Block Protection times are given in
Table 9.
The Block Protection bits are non-volatile, once
set they remain set through reset and power-
down/power-up. They are cleared by a Blocks Un-
protect command.
See Appendix C, Figure 27, Block Protect Flow-
chart and Pseudo Code, for a suggested flowchart
on using the Block Protect command.
Blocks Unprotect Command. The Blocks Un-
protect command is used to unprotect all of the
blocks. Two Bus Write cycles are required to issue
the Blocks Unprotect command; the second Bus
Write cycle starts the Program/Erase Controller.
Once the command is issued subsequent Bus
Read operations read the Status Register. See the
section on the Status Register for details on the
definitions of the Status Register bits. Typical
Block Protection times are given in Table 9.
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Block
Protect
See Appendix C, Figure 28, Blocks Unprotect
Flowchart and Pseudo Code, for a suggested flow-
chart on using the Blocks Unprotect command.
Protection Register Program Command. The
Protection Register Program command is used to
Program the 64 bit user segment of the Protection
Register. The segment is programmed 16 bits at a
time. The memory must be reset by issuing the
Read Memory Array command before the Protec-
tion Register Program command can be issued.
Two write cycles are required to issue the Protec-
tion Register Program command.
Read operations output the Status Register con-
tent after the programming has started.
The user-programmable segment can be locked
by programming bit 1 of the Protection Register
Lock location to ‘0’ (see Table 8). Bit 0 of the Pro-
tection Register Lock location locks the factory
programmed segment and is programmed to ‘0’ in
the factory. The locking of the Protection Register
is not reversible, once the lock bits are pro-
grammed no further changes can be made to the
values stored in the Protection Register, see Fig-
ure 8, Protection Register Memory Map. Attempt-
ing to program a previously protected Protection
Register will result in a Status Register error.
The Protection Register Program cannot be sus-
pended. See Appendix C, Figure 29, Protection
Register Program Flowchart and Pseudo Code,
for the flowchart for using the Protection Register
Program command.
The first bus cycle sets up the Protection
Register Program command.
The second latches the Address and the Data to
be written to the Protection Register and starts
the Program/Erase Controller.