MBM29F400TC-55/-70/-90/MBM29F400BC-55/-70/-90
Table 7 MBM29F400TC/BC Command Definitions
Second
Bus
Fourth Bus
Read/Write
Cycle
First Bus
Third Bus
Fifth Bus
Sixth Bus
Bus
Write
Cycles
Req'd
Command
Sequence
Write Cycle
Write Cycle
Write Cycle Write Cycle
Write Cycle
Addr Data Addr Data Addr Data Addr Data Addr Data Addr Data
Word
Read/Reset
Read/Reset
Autoselect
Program
1
3
3
4
6
6
XXXH F0H
—
—
—
—
—
—
RD
—
—
—
—
—
—
—
—
—
—
—
—
—
Byte
Word
Byte
Word
Byte
Word
Byte
Word
Byte
Word
Byte
555H
AAH
2AAH
555H
2AAH
555H
2AAH
555H
2AAH
555H
2AAH
555H
555H
AAAH
555H
AAAH
555H
AAAH
555H
AAAH
555H
AAAH
55H
55H
55H
55H
55H
F0H RA
90H
AAAH
555H
AAH
—
—
—
AAAH
555H
AAH
A0H PA
PD
—
—
AAAH
555H
AAH
555H
80H
2AAH
555H
2AAH
555H
555H
Chip Erase
AAH
AAH
55H
55H
10H
30H
AAAH
AAAH
AAAH
555H
AAH
555H
80H
Sector
Erase
SA
AAAH
AAAH
Sector Erase Suspend
Sector Erase Resume
Erase can be suspended during sector erase with Addr (“H” or “L”). Data (B0H)
Erase can be resumed after suspend with Addr (“H” or “L”). Data (30H)
Notes: 1. Address bits A15 to A11 = X = “H” or “L” for all address commands except or Program Address (PA) and
Sector Address (SA).
2. Bus operations are defined in Tables 2 and 3.
3. RA = Address of the memory location to be read.
PA = Address of the memory location to be programmed. Addresses are latched on the falling edge of
the WE pulse.
SA = Address of the sector to be erased. The combination of A17, A16, A15, A14, A13, and A12 will
uniquely select any sector.
4. RD = Data read from location RA during read operation.
PD = Data to be programmed at location PA. Data is latched on the falling edge of WE.
5. The system should generate the following address patterns:
Word Mode: 555H or 2AAH to addresses A0 to A10
Byte Mode: AAAH or 555H to addresses A-1 to A10
6. Both Read/Reset commands are functionally equivalent, resetting the device to the read mode.
Command Definitions
Device operations are selected by writing specific address 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 7 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
Read/Reset commands are functionally equivalent, resetting the device to the read mode. Please note that
commands are always written at DQ0 to DQ7 and DQ8 to DQ15 bits are ignored.
Read/Reset Command
The read or eset operation is initiated by writing the read/reset command sequence into the command register.
Microprocessor read cycles retrieve array data from the memory. The devices remain enabled for reads until the
command register contents are altered.
14