SCTimer0 with LPC11U66

Mr_Damian — Mon, 22 Jul 2024 07:54:53 GMT

I'm using the LPC11U66 and I'm trying to turn on a different RGB led every second. In order to turn on the led, I need to set the pin low to sink the current. The timings are correct.

The problem that I'm having is I can set the pins low, but I can't set them high to turn a specific led off, until the whole sequence is done. The led sequence should be:

Green led, Red led, Blue led, but actually I'm get mixture of colours as the led that should be off, aren't.

I was wondering if there is a setting that I'm missing ?

My code:

#include <stdint.h>

#include <chip.h>

#include "chip.h"

#include "sct_11u6x.c"

#include "iocon_11u6x.c"

const uint32_t blueLedPin = 13U;

const uint32_t greenLedPin = 2U;

const uint32_t redLedPin = 7U;

static uint32_t event;

static uint32_t state;

static uint32_t counter;

/*****************************************************************************

* Private types/enumerations/variables

****************************************************************************/

/* PWM cycle time - time of a single PWM sweep */

#define PWMCYCLERATE (120 - 1)

/*****************************************************************************

* Public types/enumerations/variables

****************************************************************************/

/*****************************************************************************

* Private functions

****************************************************************************/

/*****************************************************************************

* Public functions

****************************************************************************/

/**

* @brief Application main program

* @return Nothing (This function will not return)

void LedPwm_ConfigureSctimer0(void)

{

Chip_Clock_EnablePeriphClock(SYSCTL_CLOCK_SCT0_1);

Chip_SYSCTL_PeriphReset(RESET_SCT0);

Chip_SCT_Init(LPC_SCT0);

Chip_IOCON_PinMuxSet(LPC_IOCON, 2, 2, (IOCON_FUNC3 | IOCON_DIGMODE_EN)); // Green LED SCT0_OUT1

Chip_IOCON_PinMuxSet(LPC_IOCON, 2, 7, (IOCON_FUNC2 | IOCON_DIGMODE_EN)); // Red LED SCT0_OUT2

Chip_IOCON_PinMuxSet(LPC_IOCON, 1, 13, (IOCON_FUNC2 | IOCON_DIGMODE_EN)); // Blue LED SCT0_OUT3

LPC_SCT0->OUTPUT = (1 << 1) | (1 << 2) | (1 << 3);

/* Configure the SCT as a 32bit counter using the bus clock */

LPC_SCT0->CONFIG = SCT_CONFIG_32BIT_COUNTER | SCT_CONFIG_CLKMODE_BUSCLK | SCT_CONFIG_NORELOADL_U | (1 << 17);

LPC_SCT0->CTRL_L |= (1 << 1) | (1 << 3) | (PWMCYCLERATE << 5) ; // 100,000 Khz

// Select events that will start the counter

LPC_SCT0->START = (1 << 0) ; // Start counter on event 0

/* Setup for match mode */

LPC_SCT0->REGMODE_L = 0;

LPC_SCT0 -> OUTPUTDIRCTRL = 0;

LPC_SCT0->MATCH[1].U = 100000 - 1; // 1 seconds

LPC_SCT0->MATCH[2].U = 200000 - 1; // 1 seconds

LPC_SCT0->MATCH[3].U = 300000 - 1; // 1 seconds

LPC_SCT0->MATCH[0].U = 400000 - 1; // 1 seconds

/* Each SCTimer/PWM supports:

– 5 match/capture registers.

– 6 events.

– 8 states.

– 4 inputs and 4 outputs*/

// --------------------------------------

// Define states in which this event is enabled

LPC_SCT0->EVENT[0].STATE = (1 << 0); // Enable event 0 in state 0

// Setup the event (21.6.25)

LPC_SCT0->EVENT[0].CTRL = (1 << 0) | // MATCHSEL: Select match reg 1

(0 << 4) | // HEVENT: Not set for unified counter

(0 << 5) | // OUTSEL: N/A as match only event

(0 << 6) | // IOSEL: N/A as match only event

(0 << 10) | // IOCOND: N/A as match only event

(1 << 12) | // COMBMODE: Match only

(1 << 14) | // STATELD: Load STATEV into STATE

(1 << 15); // STATEV: Transition into state 1

// ------------------------------------

// Define states in which this event is enabled

LPC_SCT0->EVENT[1].STATE = (1 << 1); // Enable event 1 in state 1

// Setup the event (21.6.25)

LPC_SCT0->EVENT[1].CTRL = (2 << 0) | // MATCHSEL: Select match reg 2

(0 << 4) | // HEVENT: Not set for unified counter

(0 << 5) | // OUTSEL: N/A as match only event

(0 << 6) | // IOSEL: N/A as match only event

(0 << 10) | // IOCOND: N/A as match only event

(1 << 12) | // COMBMODE: Match only

(1 << 14) | // STATELD: Load STATEV into STATE

(2 << 15); // STATEV: Transition into state 2

// ----------------------------------------

// Define states in which this event is enabled

LPC_SCT0->EVENT[2].STATE = (1 << 2); // Enable event 2 in state 2

// Setup the event (21.6.25)

LPC_SCT0->EVENT[2].CTRL = (3 << 0) | // MATCHSEL: Select match reg 3

(0 << 4) | // HEVENT: Not set for unified counter

(0 << 5) | // OUTSEL: N/A as match only event

(0 << 6) | // IOSEL: N/A as match only event

(0 << 10) | // IOCOND: N/A as match only event

(1 << 12) | // COMBMODE: Match only

(1 << 14) | // STATELD: Load STATEV into STATE

(3 << 15); // STATEV: Transition into state 3

// Define states in which this event is enabled

LPC_SCT0->EVENT[3].STATE = (1 << 3); // Enable event 2 in state 2

// Setup the event (

LPC_SCT0->EVENT[3].CTRL = (0 << 0) | // MATCHSEL: Select match reg 3

(0 << 4) | // HEVENT: Not set for unified counter

(0 << 5) | // OUTSEL: N/A as match only event

(0 << 6) | // IOSEL: N/A as match only event

(0 << 10) | // IOCOND: N/A as match only event

(1 << 12) | // COMBMODE: Match only

(1 << 14) | // STATELD: Load STATEV into STATE

(0 << 15); // STATEV: Transition into state 0

LPC_SCT0->OUT[1].CLR = (1 << 0); //Clear Output 1 Green when event 0 occurs

LPC_SCT0->OUT[2].SET = (1 << 0);

LPC_SCT0->OUT[3].SET = (1 << 0);

LPC_SCT0->OUT[1].SET = (1 << 1);

LPC_SCT0->OUT[2].CLR = (1 << 1); //Clear Output 2 Red when event 1 occurs

LPC_SCT0->OUT[3].SET = (1 << 1);

LPC_SCT0->OUT[1].SET = (1 << 2);

LPC_SCT0->OUT[2].SET = (1 << 2);

LPC_SCT0->OUT[3].CLR = (1 << 2); //Clear Output 3 Blue when event 2 occurs

LPC_SCT0->OUT[1].SET = (1 << 3);

LPC_SCT0->OUT[2].SET = (1 << 3);

LPC_SCT0->OUT[3].SET = (1 << 3);

// Reset the SCTimer state to the start state

LPC_SCT0->STATE = 0;

/* Unhalt the counter to start */

LPC_SCT0->CTRL_U &= ~(1 << 2);

while (1)

{

// Read register values

state = LPC_SCT0->STATE_L;

event = LPC_SCT0->EVFLAG;

counter = LPC_SCT0->COUNT_U;

}

Re: SCTimer0 with LPC11U66

Mr_Damian — Mon, 22 Jul 2024 09:30:31 GMT

Managed to resolve this issue, by just updating the outputs that needed changing of state and ignoring the ones that need to remain the same.

Solution :

LPC_SCT0->OUT[1].CLR = (1 << 0); //Clear Output 1 Green when event 1 occurs

LPC_SCT0->OUT[1].SET = (1 << 1);

LPC_SCT0->OUT[2].CLR = (1 << 1); //Clear Output 2 Red when event 1 occurs

LPC_SCT0->OUT[2].SET = (1 << 2);

LPC_SCT0->OUT[3].CLR = (1 << 2); //Clear Output 3 Blue when event 0 occurs

LPC_SCT0->OUT[3].SET = (1 << 3);

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SCTimer0 with LPC11U66

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