LM3S101 Data Sheet
March 22, 2006
14
Preliminary
reserved
Register bits marked reserved are reserved for future use. Reserved
bits return an indeterminate value, and should never be changed.
Only write a reserved bit with its current value.
yy
:
xx
The range of register bits inclusive from xx to yy. For example, 31:15
means bits 15 through 31 in that register.
Register Bit/Field Types
This value in the register bit diagram indicates whether software
running on the controller can change the value of the bit field.
RO
Software can read this field. Always write the chip reset value.
R/W
Software can read or write this field.
R/W1C
Software can read or write this field. A write of a 0 to a W1C bit does
not affect the bit value in the register. A write of a 1 clears the value
of the bit in the register; the remaining bits remain unchanged.
This register type is primarily used for clearing interrupt status bits
where the read operation provides the interrupt status and the write
of the read value clears only the interrupts being reported at the time
the register was read.
W1C
Software can write this field. A write of a 0 to a W1C bit does not
affect the bit value in the register. A write of a 1 clears the value of
the bit in the register; the remaining bits remain unchanged. A read
of the register returns no meaningful data.
This register is typically used to clear the corresponding bit in an
interrupt register.
WO
Only a write by software is valid; a read of the register returns no
meaningful data.
Register Bit/Field Reset Value
This value in the register bit diagram shows the bit/field value after
any reset, unless noted.
0
Bit cleared to 0 on chip reset.
1
Bit set to 1 on chip reset.
–
Nondeterministic.
Pin/Signal Notation
[ ]
Pin alternate function; a pin defaults to the signal without the
brackets.
pin
Refers to the physical connection on the package.
signal
Refers to the electrical signal encoding of a pin.
assert a signal
Change the value of the signal from the logically False state to the
logically True state. For active High signals, the asserted signal
value is 1 (High); for active Low signals, the asserted signal value is
0 (Low). The active polarity (High or Low) is defined by the signal
name (see
SIGNAL
and
SIGNAL
below).
Table 0-1.
Documentation Conventions
Notation
Meaning