10
Am29F017B
P R E L I M I N A R Y
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 equipment
to automatically match a device to be programmed 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
(11.5 V to 12.5 V) on address pin
A9. Address pins A6, A1, and A0 must be as shown in
Autoselect Codes (High Voltage Method) table. In addi-
tion, when verifying sector protection, the sector ad-
dress must appear on the appropriate highest order
address bits. Refer to the corresponding Sector Ad-
dress Tables. The Command Definitions table shows
the remaining address bits that are don’t care. When all
necessary bits have been set as required, the program-
ming equipment may then read the corresponding
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 the Command Defini-
tions table. This method does not require V
ID
. See
“Command Definitions” for details on using the autose-
lect mode.
Table 3.
Am29F017B Autoselect Codes (High Voltage Method)
L = Logic Low = V
IL
, H = Logic High = V
IH
, SA = Sector Address, X = Don’t care.
Sector Group Protection/Unprotection
The hardware sector group protection feature dis-
ables both program and erase operations in any sec-
tor. Each sector group consists of four adjacent
sectors. Table 4 shows how the sectors are goruped,
and the address range that each sector group con-
tains. The hardware sector group unprotection fea-
ture re-enables both program and erase operations in
previously protected sectors.
Sector group protection/unprotection must be imple-
mented using programming equipment. The procedure
requires a high voltage (V
ID
) on address pin A9 and the
control pins. Details on this method are provided in a
supplement, publication number 21544. Contact an
AMD representative to obtain a copy of the appropriate
document.
The device is shipped with all sector groups unpro-
tected. AMD offers the option of programming and pro-
tecting 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 group is
protected or unprotected. See
“Autoselect Mode” for
details.
Table 4.
Sector Group Addresses
Temporary Sector Group Unprotect
This feature allows temporary unprotection of previ-
ously protected sectors groups to change data in-sys-
tem. The Sector Group Unprotect mode is activated
by setting the RESET# pin to V
ID
. During this mode,
formerly protected sector groups can be programmed
or erased by selecting the sector group addresses.
Once V
ID
is removed from the RESET# pin, all the
previously protected sector groups are
protected again. Figure 1 shows the algorithm, and
the Temporary Sector/Sector Group Unprotect dia-
gram shows the timing waveforms, for this feature.
Description
CE#
OE# WE# A20-A18
A17-A10
A9
A8-A7
A6
A5-A2
A1
A0
DQ7-DQ0
Manufacturer ID
:
AMD
L
L
H
X
X
V
ID
X
V
IL
X
V
IL
V
IL
01h
Device ID:
Am29F017B
L
L
H
X
X
V
ID
X
V
IL
X
V
IL
V
IH
3Dh
Sector Group
Protection
Verification
L
L
H
Sector
Group
Address
X
V
ID
X
V
IL
X
V
IH
V
IL
01h (protected)
00h (unprotected)
Sector
Group
SGA0
A20
0
A19
0
A18
0
Sectors
SA0
–
SA3
SA4
–
SA7
SA8
–
SA11
SA12
–
SA15
SA16
–
SA19
SA20
–
SA23
SA24
–
SA27
SA28
–
SA31
SGA1
0
0
1
SGA2
0
1
0
SGA3
0
1
1
SGA4
1
0
0
SGA5
1
0
1
SGA6
1
1
0
SGA7
1
1
1