23K640-ESLASHST datasheet(11/28 Pages) MICROCHIP

11 / 28 page

 2010 Microchip Technology Inc.

DS22126D-page 11

23X640

2.5

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. The STATUS register is

formatted as follows:

TABLE 2-2:

STATUS REGISTER

The mode bits indicate the operating mode of the

SRAM. The possible modes of operation are:

0 0 = Byte mode (default operation)

1 0 = Page mode

0 1 = Sequential mode

1 1 = Reserved

Write and read commands are shown in Figure 2-7 and

Figure 2-8.

The HOLD bit enables the Hold pin functionality. It must

be set to a ‘0’ before HOLD pin is brought low for HOLD

function to work properly. Setting HOLD to ‘1’ disables

feature.

Bits 2 through 5 are reserved and should always be set

to ‘0’. Bit 1 will read back as ‘1’ but should always be

written as ‘0’.

See Figure 2-7 for the RDSR timing sequence.

FIGURE 2-7:

READ STATUS REGISTER TIMING SEQUENCE (RDSR)

W/R

–

W/R

MODE MODE

HOLD

W/R = writable/readable.

1011

12131415

Instruction

Data from STATUS Register

High-Impedance

SCK

23K640-E/ST Datasheet(PDF) 11 Page - Microchip Technology

23K640-E/ST Datasheet(HTML) 11 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

Datasheet Download

Link URL