A29DL32x Series
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 itself does
not occupy any addressable memory location. The register is
composed of latches that store the commands, along with
the address and data information needed to execute the
command. The contents of the register serve as inputs to the
internal state machine. The state machine outputs dictate the
function of the device. The appropriate device bus operations
table lists the inputs and control levels required, and the
resulting output. The following subsections describe each of
these operations in further detail.
Table 1. A29DL32x Device Bus Operations
Operation
A0 – A20
(Note 1)
I/O0 - I/O7
I/O8 - I/O15
=VIH
/ACC
WP
WE
CE
OE
RESET
=VIL
BYTE
BYTE
Read
L
L
L
H
L
H
H
L/H
AIN
AIN
DOUT
DIN
DOUT
DIN
I/O8~I/O15=High-Z
I/O8~I/O14=High-Z
I/O15=A-1
Write
H
(Note 3)
Standby
X
X
H
X
High-Z
High-Z
High-Z
VCC ±
0.3 V
VCC ±
0.3 V
Output Disable
Reset
L
X
L
H
X
H
H
X
L
H
L
L/H
L/H
L/H
X
X
High-Z
High-Z
DIN
High-Z
High-Z
X
High-Z
High-Z
X
Sector Protect
(See Note 2)
VID
SA, A6=L,
A1=H, A0=L
Sector Unprotect
(See Note 2)
L
H
X
L
VID
VID
L/H
L/H
SA, A6=H,
A1=H, A0=L
DIN
X
X
Temporary Sector
Unprotect
X
X
AIN
DIN
DIN
High-Z
Legend:
L = Logic Low = VIL, H = Logic High = VIH, VID = 8.5V-10.5V, VHH = 8.5V-10.5V, X = Don’t Care, SA = Sector Address, AIN =
Address In, DIN= Data In, DOUT = Data Out
Notes:
1. Addresses are A20:A0 in word mode (
=VIH), A20: A-1 in byte mode (
=VIL).
BYTE
BYTE
2. The sector protect and sector unprotect functions may also be implemented via programming equipment. See the
“Sector/Sector Block Protection and Unprotection” section.
3. If
/ACC = VIL, the two outermost boot sectors remain protected. If
/ACC = VIH, the two outermost boot sector
WP
WP
protection depends on whether they were last protected or unprotected using the method described in “Sector/Sector Block
Protection and Unprotection”. If
/ACC = VHH all sectors will be unprotected.
WP
(November, 2007, Version 1.2)
5
AMIC Technology, Corp.