May 15, 2002
Am29DS32xG
15
A D V A N C E I N F O R M A T I O N
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 corresponding programming
algorithm. However, the autoselect codes can also be
accessed in-system through the command register.
When using programming equipment, the autoselect
mode requires V
ID
on address pin A9. Address pins
A6, A1, and A0 must be as shown in Table 7. In addi-
tion, when verifying sector protection, the sector ad-
dress must appear on the appropriate highest order
address bits (see Tables 3–6). Table 7 shows the re-
maining address bits that are don’t care. When all nec-
essary bits have been set as required, the
programming equipment may then read the corre-
sponding 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 14. This method
does not require V
ID
. Refer to the Autoselect Com-
mand Sequence section for more information.
Table 7.
Autoselect Codes, (High Voltage Method)
Legend:
T = Top Boot Block, B = Bottom Boot Block, L = Logic Low = V
IL
, H = Logic High = V
IH
, BA = Bank Address, SA = Sector Address, X
= Don’t care.
Description
CE#
OE#
WE#
A20
to
A12
A11
to
A10
A9
A8
to
A7
A6
A5
to
A2
A1
A0
DQ15 to DQ8
DQ7
to
DQ0
BYTE#
= V
IH
BYTE#
= V
IL
Manufacturer ID
:
AMD
L
L
H
BA
X
V
ID
X
L
X
L
L
X
X
01h
Device ID: Am29DS322G
L
L
H
BA
X
V
ID
X
L
X
L
H
22h
X
BBh (T), C0h (B)
Device ID: Am29DS323G
L
L
H
BA
X
V
ID
X
L
X
L
H
22h
X
B7hh (T), B8h (B)
Device ID: Am29DS324G
L
L
H
BA
X
V
ID
X
L
X
L
H
22h
X
C9h (T), CAh (B)
Sector Protection
Verification
L
L
H
SA
X
V
ID
X
L
X
H
L
X
X
01h (protected),
00h (unprotected)
SecSi
Indicator Bit
(DQ7)
L
L
H
BA
X
V
ID
X
L
X
H
H
X
X
81h (factory locked),
01h (not factory
locked)