LM3S9B81 Datasheet, PDF (427/1155 Pages) Texas Instruments – Stellaris® LM3S9B81 Microcontroller

Stellaris® LM3S9B81 Microcontroller
Table 11-3. Signals for General-Purpose Timers (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)
K11
PJ4 (10)
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)
A7
PB6 (6)
B7
PB5 (2)
TTL
Capture/Compare/PWM 5.
CCP6
G1
PD0 (6)
I/O
H2
PD2 (2)
M10
PJ3 (10)
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.
11.3
Functional Description
The main components of each GPTM block are two free-running 16-bit up/down counters (referred
to as Timer A and Timer B), two 16-bit match registers, two prescaler match registers, two 16-bit
shadow registers, and two 16-bit load/initialization registers and their associated control functions.
The exact functionality of each GPTM is controlled by software and configured through the register
interface.
Software configures the GPTM using the GPTM Configuration (GPTMCFG) register (see page 440),
the GPTM Timer A Mode (GPTMTAMR) register (see page 441), and the GPTM Timer B Mode
(GPTMTBMR) register (see page 443). When in one of the 32-bit modes, the timer can only act as
a 32-bit timer. However, when configured in 16-bit mode, the GPTM can have its two 16-bit timers
configured in any combination of the 16-bit modes.
11.3.1
GPTM Reset Conditions
After reset has been applied to the GPTM module, the module is in an inactive state, and all control
registers are cleared and in their default states. Counters Timer A and Timer B are initialized to
0xFFFF, along with their corresponding load registers: the GPTM Timer A Interval Load
(GPTMTAILR) register (see page 458) and the GPTM Timer B Interval Load (GPTMTBILR) register
(see page 459) and shadow registers: the GPTM Timer A Value (GPTMTAV) register (see page 469)
and the GPTM Timer B Value (GPTMTBV) register (see page 470). The prescale counters are
initialized to 0x00: the GPTM Timer A Prescale (GPTMTAPR) register (see page 462) and the GPTM
Timer B Prescale (GPTMTBPR) register (see page 463).
June 29, 2010
427
Texas Instruments-Advance Information