25AA320 View Datasheet(PDF) - Microchip Technology

Part Name

Description

MFG CO.

25AA320

32K SPI™ Bus Serial EEPROM

Microchip Technology 

25AA320/25LC320/25C320

3.5 Read Status Register Instruction

(RDSR)

The Read Status Register instruction (RDSR) provides

access to the Status register. The Status register may

be read at any time, even during a write cycle. The

Status register is formatted as follows:

7 654 3

2

1

0

WPEN X X X BP1 BP0 WEL WIP

The Write-In-Process (WIP) bit indicates whether the

25XX320 is busy with a write operation. When set to a

‘1’, a write is in progress; when set to a ‘0’, no write is

in progress. This bit is read-only.

The Write Enable Latch (WEL) bit indicates the status

of the write enable latch. When set to a ‘1’, the latch

allows writes to the array, when set to a ‘0’, the latch

prohibits writes to the array. The state of this bit can

always be updated via the WREN or WRDI commands

regardless of the state of write protection on the Status

register. This bit is read-only.

The Block Protection (BP0 and BP1) bits indicate

which blocks are currently write-protected. These bits

are set by the user issuing the WRSR instruction. These

bits are nonvolatile.

See Figure 3-6 for the RDSR timing sequence.

FIGURE 3-6: READ STATUS REGISTER TIMING SEQUENCE

CS

SCK

SI

SO

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

instruction

0 00 00 1 01

High-impedance

data from Status register

7 6 54 3 2 10

DS21227E-page 10

 2004 Microchip Technology Inc.

Share Link: