9

5167E–SFLSH–5/09

AT25FS010

These bits are set by using the WRSR instruction. During internal write cycles, all other com-

mands will be ignored except the RDSR instruction.

Note:

X = Don’t Care

READ PRODUCT ID (RDID): The RDID instruction allows the user to read the manufacturer ID

byte followed by two device ID bytes. The manufacturer ID is assigned by JEDEC and is 1Fh for

Atmel (see Table 4-4). The first device ID byte indicates the memory type (66h=AT25FS010) fol-

lowed by the device memory capacity byte (01h). For maximum compatibility and flexibility, two

RDID opcodes (9Fh and ABh) are supported and will perform the same operation.

The device is first selected by driving Chip Select (CS) low then the RDID opcode is shifted in on

Serial In (SI) during rising edge of clock. The 24-bit Manufacturer and Device Identification

Codes stored in memory are clocked out on Serial Output (SO) starting on the falling edge of

clock (see Figure 5-13). If CS stays low after the last bit of second device ID byte is shifted out,

the manufacturer ID and 2 byte device ID will continue to be clocked out until CS goes high. The

RDID sequence is terminated any time CS is driven high and the device will go into standby

mode.

WRITE STATUS REGISTER (WRSR): The WRSR instruction allows the user to select one of

eight levels of protection for the AT25FS010. The AT25FS010 is divided into eight blocks where

the top 1/32, 1/16, 1/8, top quarter (1/4), top half (1/2), or all of the memory blocks can be pro-

tected (locked out) from write. Any of the locked-out blocks will therefore be READ only. The

Table 4-2.

Status Register Format

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

WPEN

BP4

BP3

X

BP1

BP0

WEN

RDY

Table 4-3.

Read Status Register Bit Definition

Bit

Definition

Bit 0 (RDY)

Bit 0 = 0 (RDY) indicates the device is READY. Bit 0 = 1 indicates the

write cycle is in progress.

Bit 1 (WEN)

Bit 1 = 0 indicates the device is not WRITE ENABLED. Bit 1 = 1 indicates

the device is WRITE ENABLED.

Bit 2 (BP0)

See

Table 4-5.

Bit 3 (BP1)

See

Table 4-5.

Bit 4

Not Used

Bit 5 (BP3)

See

Table 4-5.

Bit 6 (BP4)

See

Table 4-5.

Bit 7 (WPEN)

See

Table 4-6.

Bits 0-7 are 1s during an internal write cycle.

Table 4-4.

Read Product ID (RDID)

Manufacturer ID

Device ID

Memory Type

Memory Capacity

1Fh

66h

01h