Texas Instruments TM4C1294NCPDT, Datasheet

Page: 974 / 1890

4. Configure the output state of the PWM signal (whether or not it is inverted) in the
TnPWML
field
of the GPTM Control (GPTMCTL) register.
5. If a prescaler is to be used, write the prescale value to the GPTM Timer n Prescale Register
(GPTMTnPR) .
6. If PWM interrupts are used, configure the interrupt condition in the
TnEVENT
field in the
GPTMCTL register and enable the interrupts by setting the
TnPWMIE
bit in the GPTMTnMR
register. Note that edge detect interrupt behavior is reversed when the PWM output is inverted
(see page 986).
7. Load the timer start value into the GPTM Timer n Interval Load (GPTMTnILR) register.
8. Load the GPTM Timer n Match (GPTMTnMATCHR) register with the match value.
9. Set the
TnEN
bit in the GPTM Control (GPTMCTL) register to enable the timer and begin
generation of the output PWM signal.
In PWM Time mode, the timer continues running after the PWM signal has been generated. The
PWM period can be adjusted at any time by writing the
GPTMTnILR register, and the change takes
effect at the next cycle after the write.
13.5 Register Map
Table 13-11 on page 974 lists the GPTM registers. The offset listed is a hexadecimal increment to
the register's address, relative to that timer's base address:
■ 16/32-bit Timer 0: 0x4003.0000
■ 16/32-bit Timer 1: 0x4003.1000
■ 16/32-bit Timer 2: 0x4003.2000
■ 16/32-bit Timer 3: 0x4003.3000
■ 16/32-bit Timer 4: 0x4003.4000
■ 16/32-bit Timer 5: 0x4003.5000
■ 16/32-bit Timer 6: 0x400E.0000
■ 16/32-bit Timer 7: 0x400E.1000
Note that the GP Timer module clock must be enabled before the registers can be programmed
(see page 380). There must be a delay of 3 system clocks after the Timer module clock is enabled
before any Timer module registers are accessed.
Table 13-11. Timers Register Map
See
page
Description Reset Type Name Offset
976 GPTM Configuration 0x0000.0000 RW GPTMCFG 0x000
977 GPTM Timer A Mode 0x0000.0000 RW GPTMTAMR 0x004
982 GPTM Timer B Mode 0x0000.0000 RW GPTMTBMR 0x008
986 GPTM Control 0x0000.0000 RW GPTMCTL 0x00C
990 GPTM Synchronize 0x0000.0000 RW GPTMSYNC 0x010
993 GPTM Interrupt Mask 0x0000.0000 RW GPTMIMR 0x018
June 18, 2014 974
Texas Instruments-Production Data
General-Purpose Timers