MB85AS8MT

DS501-00060-2v2-E

5



STATUS REGISTER



OP-CODE

MB85AS8MT accepts 10 kinds of command specified in op-code. Op-code is a code composed of 8 bits

shown in the table below. Do not input invalid codes other than those codes. If CS is risen while inputting

op-code, the command are not performed.

Bit No.

Bit Name

Function

7

WPEN

Not Used Bit

This is bit composed of nonvolatile memories, writing with the WRSR command

is possible. These bits are not used but they are read with the RDSR command.

Initial value is “0”.

6 to 4



Not Used Bits

These are bits composed of volatile memories, writing with the WRSR com-

mand is possible. These bits are not used but they are read with the RDSR

command.

Initial value is “000”.

3

BP1

Block Protect

This is a bit composed of nonvolatile memory. This defines size of write protect

block for the WRITE command (refer to “BLOCK PROTECT”). Writing with

the WRSR command and reading with the RDSR command are possible.

2

BP0

1

WEL

Write Enable Latch

This indicates ReRAM Array and status register are writable. The WREN com-

mand is for setting, and the WRDI command is for resetting. With the RDSR

command, reading is possible but writing is not possible with the WRSR com-

mand. WEL is reset after the following operations.

After power ON.

The rising edge of CS after WRDI command recognition.

The end of writing process after WRSR command recognition.

The end of writing process after WRITE command recognition.

0

WIP

Write In Progress

This indicates ReRAM Array and status register are in writing process. During

this writing process, any commands except RDSR will not be executed (refer to

“ WRITING OPERATION OF NONVOLATILE MEMORY 2. WIP polling”).

With the RDSR command, reading is possible but writing is not possible with

the WRSR command.

Name

Description

Op-code

WREN

Set Write Enable Latch

0000 0110B

WRDI

Reset Write Enable Latch

0000 0100B

RDSR

Read Status Register

0000 0101B

WRSR

Write Status Register

0000 0001B

READ

Read Memory Code

0000 0011B

WRITE

Write Memory Code

0000 0010B

RDID

Read Device ID

1001 1111B

RDUID

Read Device ID and Unique ID

1000 0011B

SLEEP

Enter Sleep Mode (Power Down Mode)

1011 1001B

PWDN

1110 0010B