AM29LV033C-70EI AMD (ADVANCED MICRO DEVICES), AM29LV033C-70EI Datasheet - Page 14

• Manufacturer Part Number: AM29LV033C-70EI
• Description: IC 32MEG (4M X 8-BIT) 3V SCTR
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Autoselect Mode
The autoselect mode provides manufacturer and de-
vice identification, and sector protection verification,
through identifier codes output on DQ7–DQ0. This
mode is primarily intended for programming equip-
ment to automatically match a device to be pro-
grammed with its c orresponding programm ing
algorithm. However, the autoselect codes can also be
accessed in-system through the command register.
When using programming equipment, the autoselect
mode requires V
A9. Address pins A6, A1, and A0 must be as shown in
Table 3. In addition, when verifying sector protection,
the sector address must appear on the appropriate
highest order address bits (see Table ). Table 3 shows
L = Logic Low = V
Sector/Sector Block Protection and
Unprotection
(Note: For the following discussion, the term “sector”
applies to both sectors and sector blocks. A sector
block consists of two or more adjacent sectors that are
protected or unprotected at the same time (see Table 4).
The hardware sector protection feature disables both
program and erase operations in any sector. The hard-
ware sector unprotection feature re-enables both pro-
gram and erase operations in previously protected
sectors. Sector protection/unprotection can be imple-
mented via two methods.
The primary method requires V
only, and can be implemented either in-system or via
programming equipment. Figure 2 shows the algo-
rithms and Figure 22 shows the timing diagram. This
method uses standard microprocessor bus cycle tim-
Manufacturer ID: AMD
Device ID: Am29LV033C
Sector Protection Verification
Description
IL
ID
, H = Logic High = V
(11.5 V to 12.5 V) on address pin
Table 3. Am29LV033C Autoselect Codes (High Voltage Method)
CE#
L
L
L
ID
on the RESET# pin
IH
OE#
, SA = Sector Address, X = Don’t care.
L
L
L
WE#
H
H
H
Am29LV033C
A21
A16
SA
to
X
X
A15
A10
to
X
X
X
the remaining address bits that are don’t care. When
all necessary bits have been set as required, the pro-
gramming equipment may then read the correspond-
ing identifier code on DQ7-DQ0.
To access the autoselect codes in-system, the host
system can issue the autoselect command via the
command register, as shown in Table 9. This method
does not require V
and data commands or sequences into the command
register initiates device operations. Table 9 defines the
valid register command sequences. Writing incorrect
address and data values or writing them in the im-
proper sequence resets the device to reading array
data.” for details on using the autoselect mode.
ing. For sector unprotect, all unprotected sectors must
first be protected prior to the first sector unprotect
write cycle.
The alternate method intended only for programming
equipment requires V
This method is compatible with programmer routines
written for earlier 3.0 volt-only AMD flash devices.
Publication number 22269 contains further details;
contact an AMD representative to request a copy.
The device is shipped with all sectors unprotected.
AMD offers the option of programming and protecting
sectors at its factory prior to shipping the device
through AMD’s ExpressFlash™ Service. Contact an
AMD representative for details.
It is possible to determine whether a sector is pro-
tected or unprotected. See “Autoselect Mode” for de-
tails.
V
V
V
A9
ID
ID
ID
A8
A7
to
X
X
X
A6
L
L
L
ID
. See “Writing specific address
ID
A5
A2
to
X
X
X
on address pin A9 and OE#.
A1
H
L
L
A0
H
L
L
(unprotected)
(protected)
DQ7
DQ0
01h
A3h
01h
00h
to
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