LM3S308 Luminary Micro, Inc, LM3S308 Datasheet - Page 118

• Manufacturer Part Number: LM3S308
• Description: Lm3s308 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
Internal Memory
Flash Memory Control (FMC)
Base 0x400F.D000
Offset 0x008
Type R/W, reset 0x0000.0000
118
Bit/Field
31:16
15:4
WO
RO
3
2
31
15
0
0
WO
RO
Register 3: Flash Memory Control (FMC), offset 0x008
When this register is written, the flash controller initiates the appropriate access cycle for the location
specified by the Flash Memory Address (FMA) register (see page 116). If the access is a write
access, the data contained in the Flash Memory Data (FMD) register (see page 117) is written.
This is the final register written and initiates the memory operation. There are four control bits in the
lower byte of this register that, when set, initiate the memory operation. The most used of these
register bits are the ERASE and WRITE bits.
It is a programming error to write multiple control bits and the results of such an operation are
unpredictable.
30
14
0
0
WO
RO
MERASE
29
13
reserved
0
0
WRKEY
COMT
Name
WO
RO
28
12
0
0
WO
RO
27
11
0
0
Type
R/W
R/W
WO
RO
WO
RO
26
10
0
0
reserved
WO
RO
Reset
25
0
9
0
0x0
0x0
0
0
Preliminary
WO
RO
24
0
8
0
WRKEY
Description
Flash Write Key
This field contains a write key, which is used to minimize the incidence
of accidental flash writes. The value 0xA442 must be written into this
field for a write to occur. Writes to the FMC register without this WRKEY
value are ignored. A read of this field returns the value 0.
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.
Commit Register Value
Commit (write) of register value to nonvolatile storage. A write of 0 has
no effect on the state of this bit.
If read, the state of the previous commit access is provided. If the
previous commit access is complete, a 0 is returned; otherwise, if the
commit access is not complete, a 1 is returned.
This can take up to 50 μs.
Mass Erase Flash Memory
If this bit is set, the flash main memory of the device is all erased. A
write of 0 has no effect on the state of this bit.
If read, the state of the previous mass erase access is provided. If the
previous mass erase access is complete, a 0 is returned; otherwise, if
the previous mass erase access is not complete, a 1 is returned.
This can take up to 250 ms.
WO
RO
23
0
7
0
WO
RO
22
0
6
0
WO
RO
21
0
5
0
WO
RO
20
0
4
0
COMT
R/W
WO
19
0
3
0
MERASE
R/W
WO
18
0
2
0
ERASE
R/W
WO
17
0
1
0
June 04, 2008
WRITE
R/W
WO
16
0
0
0