EN29GL256H EON [Eon Silicon Solution Inc.], EN29GL256H Datasheet - Page 33

• Manufacturer Part Number: EN29GL256H
• Description: 256 Megabit (32768K x 8-bit / 16384K x 16-bit) Flash Memory Page mode Flash Memory, CMOS 3.0 Volt-only
• Manufacturer: EON [Eon Silicon Solution Inc.]

Table 8. Secured Silicon Sector Addresses
Customer Lockable Secured Silicon Sector
The Customer Lockable Secured Silicon Sector is always shipped unprotected (DQ0 set to “1”),
allowing customers to utilize that sector in any manner they choose. If the security feature is not
required, the Secured Silicon Sector can be treated as an additional Flash memory space.
Please note the following:
• Once the Secured Silicon Sector area is protected, the Secured Silicon Sector Indicator Bit (DQ0) is
• The Secured Silicon Sector can be read any number of times, but can be programmed and locked
• The accelerated programming (ACC) is not available when the Secured Silicon Sector is enabled.
• Once the Secured Silicon Sector is locked and verified, the system must write the Exit Secured
• The address 0h~7h in Secured Silicon Sector is reserved for Factory.
Secured Silicon Sector Entry/Exit Command Sequences
The system can access the Secured Silicon Sector region by issuing the three-cycle Enter Secured
Silicon Sector command sequence. The device continues to access the Secured Silicon Sector region
until the system issues the four-cycle Exit Secured Silicon Sector command sequence.
The Secured Silicon Sector Entry Command allows the following commands to be executed
• Read customer and factory Secured Silicon areas
• Program the customer Secured Silicon Sector
After the system has written the Enter Secured Silicon Sector command sequence, it may read the
Secured Silicon Sector by using the addresses normally occupied by sector SA0 within the memory
array. This mode of operation continues until the system issues the Exit Secured Silicon Sector
command sequence, or until power is removed from the device.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
000000h-000007h
000008h-00007Fh
permanently set to “0.”
only once. The Secured Silicon Sector lock must be used with caution as once locked, there is no
procedure available for unlocking the Secured Silicon Sector area and none of the bits in the
Secured Silicon Sector memory space can be modified in any way.
Silicon Sector Region command sequence which return the device to the memory array at sector 0.
Secured Silicon Sector Address Range
Reserve for Factory
Determined by customer
Rev. G, Issue Date: 2011/01/17
33
©2004 Eon Silicon Solution, Inc.,
EN29GL256H/L
www.eonssi.com