Register 3: Flash Memory Control (FMC), offset 0x008
When this register is written, the Flash memory controller initiates the appropriate access cycle for
the location specified by the
Flash Memory Address (FMA)
register (see page 625). If the access
is a write access, the data contained in the
Flash Memory Data (FMD)
register (see page 626) is
written to the specified address.
For non-volatile registers,
FMPREn
,
FMPPEn
,
USER_REGn
, and USER_REGn, the respective
register is programmed with the value to be written rather than the
FMD
register.
This register must be the final register written and initiates the memory operation. The four control
bits in the lower byte of this register are used to initiate memory operations.
Care must be taken not to set multiple control bits as the results of such an operation are
unpredictable.
Flash Memory Control (FMC)
Base 0x400F.D000
Offset 0x008
Type RW, reset 0x0000.0000
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
WRKEY
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
Type
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Reset
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
WRITE
ERASE
MERASE
COMT
reserved
RW
RW
RW
RW
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
Type
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Reset
Description
Reset
Type
Name
Bit/Field
Flash Memory Write Key
This field contains a write key, which is used to minimize the incidence
of accidental Flash memory writes. The value 0xA442 or the
PEKEY
value in the
FLPEKEY
register must be written into this field for a Flash
memory write to occur. The use of 0xA442 or
PEKEY
is dependent on
the value of the
KEY
bit in the
BOOTCFG
register at 0x1D0.
Writes to the
FMC
register without this
WRKEY
value are ignored. A read
of this field returns the value 0.
0x0000
WO
WRKEY
31:16
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
0x00
RO
reserved
15:4
627
June 18, 2014
Texas Instruments-Production Data
Tiva
™
TM4C1294NCPDT Microcontroller