HY29DS162 Datasheet, PDF (14/48 Pages) Hynix Semiconductor – 16 Megabit (2M x 8/1M x 16) Super-Low Voltage, Dual Bank, Simultaneous Read/Write, Flash Memory

HY29DS162/HY29DS163
cycle. Also, the unprotect procedure will cause
all sectors to become unprotected, thus, sector
groups that require protection must be protected
again after the unprotect procedure is run.
This procedure requires V_ID on the RESET# pin
and uses standard microprocessor bus cycle tim-
ing to implement sector unprotection. The flow
chart in Figure 2 illustrates the algorithm.
Temporary Sector Unprotect Operation
This feature allows temporary unprotection of pro-
tected sectors to allow changing the data in-sys-
tem. Temporary Sector Unprotect mode is acti-
vated by setting the RESET# pin to V_ID. While in
this mode, formerly protected sectors can be pro-
grammed or erased by invoking the appropriate
commands (see Device Commands section).
Once V_ID is removed from RESET#, all the previ-
ously protected sector groups are protected again.
Figure 3 illustrates the algorithm.
NOTE: If WP#/ACC = V_IL, the two outermost boot sec-
tors remain protected.
Electronic ID Operation (High Voltage Method)
The Electronic ID mode provides manufacturer and
device identification, sector protection verification
and Sec² region protection status through identi-
fier codes output on DQ[7:0]. This mode is in-
tended primarily for programming equipment to au-
tomatically match a device to be programmed with
its corresponding programming algorithm.
Two methods are provided for accessing the Elec-
tronic ID data. The first requires V_ID on address
pin A[9], with additional requirements for obtain-
ing specific data items listed in Table 6. The Elec-
tronic ID data can also be obtained by the host
through specific commands issued via the com-
mand register, as described later in the ‘Device
Commands’ section of this data sheet.
While in the high-voltage Electronic ID mode, the
system may read at specific addresses to obtain
certain device identification and status informa-
tion:
n A read cycle at address 0xXXX00 retrieves the
manufacturer code.
n A read cycle at address 0xXXX01 in word mode
or 0xXXX02 in byte mode returns the device
code.
START
(Note: All sector groups
must be protected prior to
sector unprotect)
TRYCNT = 1
GNUM = 0
RESET# = V_ID
Wait 1 us
Write 0x60 to device
Set Address:
A[6] = 1, A]1] = 1, A]0] = 0
Write 0x60 to Address
Wait 15 ms
Set Address:
A[19:12] = Group GNUM
A[6] = 1, A]1] = 1, A]0] = 0
Write 0x40 to Address
Wait 1 us
Read from Address
RESET# = V_IH
Write Reset Command
SECTOR GROUP
UNPROTECT COMPLETE
NO
Data = 0x00?
TRYCNT = 1000? ^YES
YES
YES
GNUM = 16?
NO
GNUM = GNUM + 1
NO
Increment TRYCNT
DEVICE FAILURE
Figure 2. Sector Group Unprotect Algorithm
14
r1.3/Apr 01