D A T A S H E E T
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
Addresses
(Note 1)
Data
(DQ0–DQ15)
Operation
Read
CE#
L
OE# WE# RESET# CLK LBA# BAA#
A
D
L
H
L
H
H
X
X
X
X
X
X
IN
OUT
A
D
Write
L
H
IN
IN
V
±
V
CC
CC
Standby
X
X
X
X
X
X
HIGH Z
0.3 V
± 0.3 V
Output Disable
Reset
L
H
X
H
X
H
L
X
X
X
X
X
X
HIGH Z
X
HIGH Z
HIGH Z
X
Sector Address,
A6 = L, A1 = H,
A0 = L
V
D
Sector Protect (Note 2)
L
H
L
X
X
X
ID
IN
Sector Address,
A6 = H, A1 = H,
A0 = L
V
D
Sector Unprotect (Note 2)
L
H
X
L
X
X
X
X
X
X
ID
IN
V
A
Temporary Sector Unprotect
X
X
HIGH Z
ID
IN
Burst Read Operations
A
Load Starting Burst Address
L
L
X
H
H
H
H
H
L
H
L
X
IN
Advance burst to Next address (no data
presented on the data bus
H
X
HIGH Z
Advance burst to Next address
(appropriate data presented on the data
bus
Data Out
DQ0-DQ15
L
L
H
H
H
L
X
X
Terminate Current burst Read Cycle
H
L
X
X
H
H
H
H
X
L
X
H
HIGH Z
X
Terminate Current burst Read Cycle;
Start New Burst Read Cycle
A
IN
Burst Suspend: (All data is retained
internally in the device)
L
L
L
H
L
L
H
H
H
H
H
H
X
H
H
H
H
H
L
X
X
X
HIGH Z
Burst Resume: (Same data as
Burst suspend)
Data Out
DQ0–DQ15
Burst Resume: (Incremented data from
Burst Suspend)
Data Out
DQ0–DQ15
Legend:
L = Logic Low = V , H = Logic High = V , SA = Sector Address, X = Don’t care.
IL
IH
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.
8
Am29BL802C
22371C7 November 3, 2006