PWMA1

Pulse width modulation. More...

Files
file	PWMA1.h
	Pulse width modulation.

Macros
#define	PWMUSELFCLK   2
	use PWMUSELFCLK to select LFCLK
#define	PWMUSEMFCLK   4
	use PWMUSEMFCLK to select MFCLK
#define	PWMUSEBUSCLK   8
	use PWMUSEBUSCLK to select bus CLK

Functions
void	PWMA1_Init (uint32_t timerClkSrc, uint32_t timerClkPrescale, uint32_t period, uint32_t duty0, uint32_t duty1)
	Initialize PWMA1. More...
void	PWMA1_SetDuty (uint32_t duty0, uint32_t duty1)
	Set duty cycles. More...
void	PWMA1_Forward (uint32_t duty0)
	Motor forward. More...
void	PWMA1_Backward (uint32_t duty1)
	Motor backward. More...
void	PWMA1_Break (void)
	Motor break. More...
void	PWMA1_Coast (void)
	Motor coast. More...

Detailed Description

Pulse width modulation.

PWM pins on the MSPM0G3507

Pin	Description
PB4	CCP0 PWM output
PB1	CCP1 PWM output

Function Documentation

PWMA1_Backward()

void PWMA1_Backward

(

uint32_t

duty1

)

Motor backward.

Set duty cycle on PB1 (time low), and set PB4 high.

Parameters

duty1

sets the duty cycle on PB1

Returns

none

Note

assumes PWMA1_Init was called

See also

PWMA1_Init

PWMA1_Break()

void PWMA1_Break

(

void

)

Motor break.

Set PB1 high, and set PB4 high.

Parameters

none

Returns

none

Note

assumes PWMA1_Init was called

See also

PWMA1_Init

PWMA1_Coast()

void PWMA1_Coast

(

void

)

Motor coast.

Set PB1 low, and set PB4 low. Goes into sleep mode

Parameters

none

Returns

none

Note

assumes PWMA1_Init was called

See also

PWMA1_Init

PWMA1_Forward()

void PWMA1_Forward

(

uint32_t

duty0

)

Motor forward.

Set duty cycle on PB4 (time low), and set PB1 high.

Parameters

duty0

sets the duty cycle on PB4

Returns

none

Note

assumes PWMA1_Init was called

See also

PWMA1_Init

PWMA1_Init()

void PWMA1_Init	(	uint32_t	timerClkSrc,
		uint32_t	timerClkPrescale,
		uint32_t	period,
		uint32_t	duty0,
		uint32_t	duty1
	)

Initialize PWMA1.

Initialize PWMA1 outputs on PB4, PB1. Rising edge synchronized. timerClkDivRatio = 1. Once started, hardware will continuously output the waves.

• timerClkSrc =
  • 2 for 32768 Hz LFCLK
  • 4 for 4MHz MFCLK (not tested)
  • 8 for 80/32/4 BUSCLK
• A0/A1 is on Power domain PD1
  • 32MHz bus clock, BUSCLK clock is 32MHz
  • 40MHz bus clock, BUSCLK clock is ULPCLK 20MHz
  • 80MHz bus clock, BUSCLK clock is ULPCLK 40MHz
• PWMFreq = (timerClkSrc / (timerClkDivRatio * (timerClkPrescale + 1) * period))
  • For example, source=LFCLK, prescale = 0, period = 1000, PWM frequency = 32.768 Hz
  • For example, source=BUSCLK, 80MHz bus, prescale=39, period = 10000, PWM frequency = 200Hz

Parameters

timerClkSrc	is 2 4 or 8
timerClkPrescale	divide clock by timerClkPrescale+1, 0 to 255
period	sets the PWM period
duty0	sets the duty cycle on PB4
duty1	sets the duty cycle on PB1

Returns

none

Note

Will call LaunchPad_Init to reset and activate power

See also

PWMA1_SetDuty

PWMA1_SetDuty()

void PWMA1_SetDuty	(	uint32_t	duty0,
		uint32_t	duty1
	)

Set duty cycles.

Set duty cycles on PB4, PB1.

Parameters

duty0	sets the duty cycle on PB4
duty1	sets the duty cycle on PB1

Returns

none

Note

assumes PWMA1_Init was called

See also

PWMA1_Init