AM29F100B-75EI データシートの表示（PDF） - Advanced Micro Devices
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AM29F100B-75EI
Advanced Micro Devices
AM29F100B-75EI Datasheet PDF : 34 Pages
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AMD
Table 3.1 Sector Address Tables (Am29F100T)
A15
A14
A13
A12
(x8) Address Range
(x16) Address Range
SA0
0
X
X
X
00000h–0FFFFh
00000h–07FFFh
SA1
1
0
X
X
10000h–17FFFh
08000h–0BFFFh
SA2
1
1
0
0
18000h–19FFFh
0C000h–0CFFFh
SA3
1
1
0
1
1A000h–1BFFFh
0D000h–0DFFFh
SA4
1
1
1
X
1C000h–1FFFFh
0E000h–0FFFFh
Table 3.2 Sector Address Tables (Am29F100B)
A15
A14
A13
A12
(x8) Address Range
(x16) Address Range
SA0
0
0
0
X
00000h–03FFFh
00000h–01FFFh
SA1
0
0
1
0
04000h–05FFFh
02000h–02FFFh
SA2
0
0
1
1
06000h–07FFFh
03000h–03FFFh
SA3
0
1
X
X
08000h–0FFFFh
04000h–07FFFh
SA4
1
X
X
X
10000h–1FFFFh
08000h–0FFFFh
Write
Device erasure and programming are accomplished via
the command register. The contents of the register
serve as inputs to the internal state machine. The state
machine outputs dictate the function of the device.
The command register itself does not occupy any ad-
dressable memory location. The register is a latch used
to store the commands, along with the address and data
information needed to execute the command. The com-
mand register is written to by bringing WE to VIL, while
CE is at VIL and OE is at VIH. Addresses are latched on
the falling edge of WE or CE, whichever happens later;
while data is latched on the rising edge of WE or CE,
whichever happens first. Standard microprocessor write
timings are used.
Refer to AC Write Characteristics and the Erase/Pro-
gramming Waveforms for specific timing parameters.
Sector Protection
The Am29F100 features hardware sector protection.
This feature will disable both program and erase
operations in any combination of ten sectors of memory.
The sector protect feature is enabled using
programming equipment at the user’s site. The device is
shipped with all sectors unprotected. Alternatively, AMD
may program and protect sectors in the factory prior to
shipping the device (AMD’s ExpressFlash Service).
It is possible to determine if a sector is protected in the
system by writing an Autoselect command. Performing
a read operation at the address location XX02H, where
the higher order address bits A12 – A15 is the desired
sector address, will produce a logical “1” at DQ0 for a
protected sector. See Table 2.1 for Autoselect codes.
Temporary Sector Unprotect
This feature allows temporary unprotection of previ-
ously protected sectors of the Am29F100 device in or-
der to change data in-system. The Sector Unprotect
mode is activated by setting the RESET pin to high volt-
age (12 V). During this mode, formerly protected sectors
can be programmed or erased by selecting the sector
addresses. Once the 12 V is taken away from the
RESET pin, all the previously protected sectors will be
protected again. Refer to Figures 17 and 18.
Command Definitions
Device operations are selected by writing specific ad-
dress and data sequences into the command register.
Writing incorrect address and data values or writing
them in the improper sequence will reset the device
to the read mode. Table 4 defines the valid register
command sequences. Note that the Erase Suspend
(B0H) and Erase Resume (30H) commands are valid
only while the Sector Erase operation is in progress.
Moreover, both Reset/Read commands are functionally
equivalent, resetting the device to the read mode.
Am29F100T/Am29F100B
1-41
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