8

Am29BL802C

22371C7 November 3, 2006

D A TA

SH EET

DEVICE BUS OPERATIONS

This section describes the requirements and use of the

device bus operations, which are initiated through the

internal command register. The command register it-

self does not occupy any addressable memory loca-

tion. The register is composed of latches that store the

commands, along with the address and data informa-

tion needed to execute the command. The contents of

the register serve as inputs to the internal state ma-

chine. The state machine outputs dictate the function of

the device. Table 1 lists the device bus operations, the

inputs and control levels they require, and the resulting

output. The following subsections describe each of

these operations in further detail.

Table 1.

Device Bus Operations

Legend:

Notes:

1. Addresses are A18:A0.

2. The sector protect and sector unprotect functions may also be implemented via programming equipment. See the “Sector

Protection/Unprotection” section.

Operation

CE#

OE# WE#

RESET#

CLK

LBA# BAA#

Addresses

(Note 1)

Data

(DQ0–DQ15)

Read

L

L

H

H

X

X

X

Write

L

H

L

H

X

X

X

Standby

0.3 V

XX

± 0.3 V

XX

X

X

HIGH Z

Output Disable

L

H

H

H

X

X

X

HIGH Z

HIGH Z

Reset

X

X

X

L

X

X

X

X

HIGH Z

Sector Protect (Note 2)

L

H

L

XX

X

Sector Address,

A6 = L, A1 = H,

A0 = L

Sector Unprotect (Note 2)

L

H

L

XX

X

Sector Address,

A6 = H, A1 = H,

A0 = L

Temporary Sector Unprotect

X

X

X

XX

X

HIGH Z

Burst Read Operations

Load Starting Burst Address

L

X

H

H

L

H

X

Advance burst to Next address (no data

presented on the data bus

LH

H

H

H

L

X

HIGH Z

Advance burst to Next address

(appropriate data presented on the data

bus

LL

H

H

H

L

X

Data Out

DQ0-DQ15

Terminate Current burst Read Cycle

H

X

H

H

X

X

X

HIGH Z

Terminate Current burst Read Cycle;

Start New Burst Read Cycle

LX

H

H

L

H

X

Burst Suspend: (All data is retained

internally in the device)

LH

H

H

X

H

H

X

HIGH Z

Burst Resume: (Same data as

Burst suspend)

LL

H

H

H

H

X

Data Out

DQ0–DQ15

Burst Resume: (Incremented data from

Burst Suspend)

LL

H

H

H

L

X

Data Out

DQ0–DQ15