LM3S1651 Datasheet, PDF (465/1033 Pages) Texas Instruments – ARM and Thumb are registered trademarks and Cortex is a trademark

Stellaris^® LM3S1651 Microcontroller
Table 10-3. General-Purpose Timers Signals (108BGA) (continued)
Pin Name
Pin Number Pin Mux / Pin Pin Type Buffer Type^a Description
Assignment
CCP4
L2
PC7 (1)
I/O
L1
PC4 (6)
M6
PA7 (2)
K4
PF7 (1)
A4
PE2 (1)
C6
PD5 (2)
TTL
Capture/Compare/PWM 4.
CCP5
B3
PE5 (1)
I/O
H2
PD2 (4)
L1
PC4 (1)
C10
PG7 (8)
M7
PG5 (1)
A7
PB6 (6)
B7
PB5 (2)
TTL
Capture/Compare/PWM 5.
CCP6
G1
PD0 (6)
I/O
H2
PD2 (2)
A12
PE1 (5)
C9
PH0 (1)
B7
PB5 (3)
TTL
Capture/Compare/PWM 6.
CCP7
G2
PD1 (6)
I/O
H1
PD3 (2)
C8
PH1 (1)
A7
PB6 (2)
B4
PE3 (5)
TTL
Capture/Compare/PWM 7.
a. The TTL designation indicates the pin has TTL-compatible voltage levels.
10.3
Functional Description
The main components of each GPTM block are two free-running up/down counters (referred to as
Timer A and Timer B), two match registers, two prescaler match registers, two shadow registers,
and two load/initialization registers and their associated control functions. The exact functionality of
each GPTM is controlled by software and configured through the register interface. Timer A and
Timer B can be used individually, in which case they have a 16-bit counting range. In addition, Timer
A and Timer B can be concatenated to provide a 32-bit counting range. Note that the prescaler can
only be used when the timers are used individually.
The available modes for each GPTM block are shown in Table 10-4 on page 465. Note that when
counting down in one-shot or periodic modes, the prescaler acts as a true prescaler and contains
the least-significant bits of the count. When counting up in one-shot or periodic modes, the prescaler
acts as a timer extension and holds the most-significant bits of the count. In input edge count mode,
the prescaler always acts as a timer extension, regardless of the count direction.
Table 10-4. General-Purpose Timer Capabilities
Mode
One-shot
Periodic
RTC
Edge Count
Edge Time
Timer Use
Individual
Concatenated
Individual
Concatenated
Concatenated
Individual
Individual
Count Direction
Up or Down
Up or Down
Up or Down
Up or Down
Up
Down
Down
Counter Size
16-bit
32-bit
16-bit
32-bit
32-bit
16-bit
16-bit
Prescaler Size^a
8-bit
-
8-bit
-
-
8-bit
-
January 21, 2012
465
Texas Instruments-Production Data