PWM ISSUE - LPC 55s16 Microntroller

[Arularasan]

I configured PWM pulse port-1 pin-4 its working ,but,

when i try to generate PWM pulse in port-0 pin-31 its NOT working.

please update me if any changes to my below configuration 

int main(void)

{

ctimer_config_t config;

uint32_t srcClock_Hz;

uint32_t timerClock;

/* Init hardware*/

/* set BOD VBAT level to 1.65V */

POWER_SetBodVbatLevel(kPOWER_BodVbatLevel1650mv, kPOWER_BodHystLevel50mv, false);

/* attach 12 MHz clock to FLEXCOMM0 (debug console) */

CLOCK_AttachClk(BOARD_DEBUG_UART_CLK_ATTACH);

/* Use 12 MHz clock for some of the Ctimers */

CLOCK_AttachClk(kFRO_HF_to_CTIMER2);

BOARD_InitBootPins();

BOARD_InitBootClocks();

BOARD_InitDebugConsole();

/* CTimer0 counter uses the AHB clock, some CTimer1 modules use the Aysnc clock */

srcClock_Hz = CTIMER_CLK_FREQ;

PRINTF("CTimer example to generate a PWM signal\r\n");

PRINTF("This example uses interrupts to update the PWM duty cycle\r\n");

CTIMER_GetDefaultConfig(&config);

timerClock = srcClock_Hz / (config.prescale + 1);

CTIMER_Init(CTIMER, &config);

CTIMER_RegisterCallBack(CTIMER, &ctimer_callback[0], kCTIMER_SingleCallback);

/* Get the PWM period match value and pulse width match value of 2Khz PWM signal */

CTIMER_GetPwmPeriodValue(20, dutyCycle, timerClock);

CTIMER_SetupPwmPeriod(CTIMER, CTIMER_MAT_PWM_PERIOD_CHANNEL, CTIMER_MAT_OUT, g_pwmPeriod, g_pulsePeriod, true);

CTIMER_StartTimer(CTIMER);

while (1)

{

}

}

[putavi]

This issue has bother me for a week. finally find the working solution. Thanks.

[xiangjun_rong · Accepted solution]

Hi,

First of all, pls download data sheet of lpc5516 and check it in pin description. For example, the PIO0-0 can function as CTIMER0_MAT0, which means that the pin can function to output PWM signal.

PIO0_3 CTIMER0_MAT1

PIO0_5 CTIMER3_MAT0

PIO0_10 CTIMER2_MAT0

.....

In conclusion, all the CTIMERx_MATy pin can function as CTIMER PWM signal. In general, the MATCH0 register is used to configure the PWM period, so the CATIMERx_MAT0 is not used to output PWM. Of course, if you use the other match reg to control period, the MAT0 can be used to output PWM.

xiangjun_rong_0-1699839496009.png

2)The SDK has example to have the CTIMER output PWM signal

xiangjun_rong_1-1699840108212.png

In the ctimer_PWM example, the PWM signal can output from PIO1_4 pin which multiplexed with CTIMER2_MAT1.

The example uses CTIMER2 MAT2, we use the follow Macro

#define CTIMER CTIMER2 /* Timer 2 */
#define CTIMER_MAT_OUT kCTIMER_Match_1 /* Match output 1 */

In the pin_mux.c file, the following is defined:

const uint32_t port1_pin4_config = (/* Pin is configured as CTIMER2_MAT1 */
IOCON_PIO_FUNC3 |
/* No addition pin function */
IOCON_PIO_MODE_INACT |
/* Standard mode, output slew rate control is enabled */
IOCON_PIO_SLEW_STANDARD |
/* Input function is not inverted */
IOCON_PIO_INV_DI |
/* Enables digital function */
IOCON_PIO_DIGITAL_EN |
/* Open drain is disabled */
IOCON_PIO_OPENDRAIN_DI);
/* PORT1 PIN4 (coords: 1) is configured as CTIMER2_MAT1 */
IOCON_PinMuxSet(IOCON, 1U, 4U, port1_pin4_config);

3)If you want to set the CTIMER2_MAT2 (pin PIO0_11) to output PWM. Pls try to use the code:

#define IOCON_PIO_FUNC2

 const uint32_t port0_pin11_config = (/* Pin is configured as CTIMER2_MAT2 */
IOCON_PIO_FUNC2 |
/* No addition pin function */
IOCON_PIO_MODE_INACT |
/* Standard mode, output slew rate control is enabled */
IOCON_PIO_SLEW_STANDARD |
/* Input function is not inverted */
IOCON_PIO_INV_DI |
/* Enables digital function */
IOCON_PIO_DIGITAL_EN |
/* Open drain is disabled */
IOCON_PIO_OPENDRAIN_DI);
/* PORT0 PIN11 (coords: 1) is configured as CTIMER2_MAT2 */
IOCON_PinMuxSet(IOCON, 0U, 11U, port0_pin11_config);

In the main.c

#define CTIMER_MAT_OUT2 2
/* CTimer0 counter uses the AHB clock, some CTimer1 modules use the Aysnc clock */
srcClock_Hz = CTIMER_CLK_FREQ;

PRINTF("CTimer example to generate a PWM signal\r\n");

CTIMER_GetDefaultConfig(&config);
timerClock = srcClock_Hz / (config.prescale + 1);

CTIMER_Init(CTIMER, &config);

/* Get the PWM period match value and pulse width match value of 20Khz PWM signal with 20% dutycycle */
CTIMER_GetPwmPeriodValue(20000, 20, timerClock);
CTIMER_SetupPwmPeriod(CTIMER, CTIMER_MAT_PWM_PERIOD_CHANNEL, CTIMER_MAT_OUT, g_pwmPeriod, g_pulsePeriod, false);
CTIMER_SetupPwmPeriod(CTIMER, CTIMER_MAT_PWM_PERIOD_CHANNEL, CTIMER_MAT_OUT2, g_pwmPeriod, g_pulsePeriod, false);
CTIMER_StartTimer(CTIMER);

Pls have a try.

Hope it is helpful

BR

XiangJun Rong

[JJ3]

Dear Xiangjun,

I try to use the simple_pwm_interrupt demo to control the rgb led, how can I control the led on delay by the pwm cycle count insteal of the function bsp_delay_time.

Best Wish!