MBM29DL16XTE/BE70/90
• HiddenROM Protect Command
There are two methods to protect the HiddenROM area. One is to write the sector group protect setup command
(60h), set the sector address in the HiddenROM area and (A6, A1, A0) = (0,1,0), and write the sector group
protect command (60h) during the HiddenROM mode. The same command sequence could be used because
except that it is in the HiddenROM mode and that it does not apply high voltage to RESET pin, it is the same as
the extension sector group protect in the past. Please refer to “Extended Command (3) Extended Sector Group
Protection” for details of extention sector group protect setting.
The other is to apply high voltage (VID) to A9 and OE, set the sector address in the HiddenROM area and (A6,
A1, A0) = (0,1,0), and apply the write pulse during the HiddenROM mode. To verify the protect circuit, apply high
voltage (VID) to A9, specify (A6, A1, A0) = (0,1,0) and the sector address in the HiddenROM area, and read. When
“1” appears to DQ0, the protect setting is completed. “0” will appear to DQ0 if it is not protected. Please apply
write pulse agian. The same command sequence could be used for the above method because other than the
HiddenROMmode, itisthesameasthesectorgroupprotectinthepast. Pleasereferto “SectorGroupProtection”
in ■FUNCTIONAL DESCRIPTION for details of sector group protect setting
Other sector group will be effected if the address other than the HiddenROM area is selected for the sector group
address, so please be carefull. Once it is protected, protection can not be cancelled, so please pay closest
attention.
• Write Operation Status
Detailed in “Hardware Sequence Flags Table” are all the status flags that can determine the status of the bank
for the current mode operation. The read operation from the bank where is not operate Embedded Algorithm
returns a data of memory cell. These bits offer a method for determining whether a Embedded Algorithm is
completed properly. Information on DQ2 is address sensitive. This means that if an address from an erasing
sector is consectively read, then the DQ2 bit will toggle. However, DQ2 will not toggle if an address from a non-
erasingsectorisconsectivelyread. Thisallowstheusertodeterminewhichsectorsareerasingandwhicharenot.
The status flag is not output from bank (non-busy bank) not executing Embedded Algorithm. For example, there
is bank (busy bank) which is now executing Embedded Algorithm. When the read sequence is [1] <busy bank>,
[2] <non-busy bank>, [3] <busy bank>, the DQ6 is toggling in the case of [1] and [3]. In case of [2], the data of
memory cell is outputted. In the erase-suspend read mode with the same read sequence, DQ6 will not be toggled
in the [1] and [3].
In the erase suspend read mode, DQ2 is toggled in the [1] and [3]. In case of [2], the data of memory cell is
outputted.
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SPANSION [ SPANSION ]
