M50FLW080A datasheet(29/64 Pages) STMICROELECTRONICS

29 / 64 page

M50FLW080A, M50FLW080B

Command interface

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4.10

Clear Status Register command

The Clear Status Register command is used to reset Status Register bits SR1, SR3, SR4

and SR5 to ‘0’. One Bus Write is required to issue the command. Once the command is

issued, the device returns to its previous mode, subsequent Bus Read operations continue

to output the data from the same area, as before.

Once set, these Status Register bits remain set. They do not automatically return to ‘0’, for

example, when a new program or erase command is issued. If an error has occurred, it is

essential that any error bits in the Status Register are cleared, by issuing the Clear Status

4.11

Program/Erase Suspend command

The Program/Erase Suspend command is used to pause the Program/Erase Controller

during a program or Sector/Block Erase operation. One Bus Write cycle is required to issue

the command.

Once the command has been issued, it is necessary to poll the Program/Erase Controller

Status bit until the Program/Erase Controller has paused. No other commands are accepted

until the Program/Erase Controller has paused. After the Program/Erase Controller has

paused, the device continues to output the contents of the Status Register until another

command is issued.

During the polling period, between issuing the Program/Erase Suspend command and the

Program/Erase Controller pausing, it is possible for the operation to complete. Once the

Program/Erase Controller Status bit indicates that the Program/Erase Controller is no longer

active, the Program Suspend Status bit or the Erase Suspend Status bit can be used to

determine if the operation has completed or is suspended.

During Program/Erase Suspend, the Read Memory Array, Read Status Register, Read

Electronic Signature and Program/Erase Resume commands will be accepted by the

Command Interface. Additionally, if the suspended operation was Sector Erase or Block

Erase then the program command will also be accepted. However, it should be noted that

only the Sectors/Blocks not being erased may be read or programmed correctly.

See Figure 24, and Figure 27, for suggested flowcharts on using the Program/Erase

Suspend command. Typical times and delay durations are given in Table 18.

4.12

Program/Erase Resume command

The Program/Erase Resume command can be used to restart the Program/Erase Controller

after a Program/Erase Suspend has paused it. One Bus Write cycle is required to issue the

command. Once the command is issued, subsequent Bus Read operations read the

contents of the Status Register.

M50FLW080A датащи(PDF) 29 Page - STMicroelectronics