[参考译文] TM4C1292NCPDT：将 PWM 发生器模块偏移180度

您好！

 是否仍需要有关设置180度异相 PWM 的帮助？ TivaWare API 本身不支持它。 您必须绕过 API 才能实现这一点。 我能够获得两对死区信号、并且两对彼此之间具有180度的相位差。 请参见下方的。  

我修改库存示例 pwm_dead_band.c  

//*****************************************************************************
//
// pwm_dead_band.c - Example demonstrating the PWM dead-band generator.
//
// Copyright (c) 2019-2020 Texas Instruments Incorporated.  All rights reserved.
// Software License Agreement
// 
// Texas Instruments (TI) is supplying this software for use solely and
// exclusively on TI's microcontroller products. The software is owned by
// TI and/or its suppliers, and is protected under applicable copyright
// laws. You may not combine this software with "viral" open-source
// software in order to form a larger program.
// 
// THIS SOFTWARE IS PROVIDED "AS IS" AND WITH ALL FAULTS.
// NO WARRANTIES, WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT
// NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. TI SHALL NOT, UNDER ANY
// CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
// DAMAGES, FOR ANY REASON WHATSOEVER.
// 
// This is part of revision 2.2.0.295 of the EK-TM4C1294XL Firmware Package.
//
//*****************************************************************************

#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_types.h"
#include "inc/hw_memmap.h"
#include "inc/hw_pwm.h"

#include "driverlib/debug.h"
#include "driverlib/gpio.h"
#include "driverlib/pin_map.h"
#include "driverlib/pwm.h"
#include "driverlib/rom.h"
#include "driverlib/rom_map.h"
#include "driverlib/sysctl.h"
#include "driverlib/uart.h"
#include "utils/uartstdio.h"

//*****************************************************************************
//
//! \addtogroup pwm_examples_list
//! <h1>PWM Dead-band Generator Demo (pwm_dead_band)</h1>
//!
//! The example configures the PWM0 block to generate a 25% duty cycle signal
//! on PF2 with dead-band generation.  This will produce a complement of PF2 on
//! PF3 (75% duty cycle).  The dead-band generator is set to have a 10us delay
//! on the rising and falling edges of the PF2 PWM signal.
//!
//! This example uses the following peripherals and I/O signals.
//! - GPIO Port F peripheral (for PWM pins)
//! - M0PWM2 - PF2
//! - M0PWM3 - PF3
//!
//! UART0, connected to the Virtual Serial Port and running at 115,200, 8-N-1,
//! is used to display messages from this application.
//
//*****************************************************************************

//*****************************************************************************
//
// The variable g_ui32SysClock contains the system clock frequency in Hz.
//
//*****************************************************************************
uint32_t g_ui32SysClock;

//*****************************************************************************
//
// The error routine that is called if the driver library encounters an error.
//
//*****************************************************************************
#ifdef DEBUG
void
__error__(char *pcFilename, uint32_t ui32Line)
{
}
#endif

//*****************************************************************************
//
// Configure the UART and its pins.  This must be called before UARTprintf().
//
//*****************************************************************************
void
ConfigureUART(void)
{
    //
    // Enable the GPIO Peripheral used by the UART.
    //
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA);

    //
    // Enable UART0.
    //
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_UART0);

    //
    // Configure GPIO Pins for UART mode.
    //
    MAP_GPIOPinConfigure(GPIO_PA0_U0RX);
    MAP_GPIOPinConfigure(GPIO_PA1_U0TX);
    MAP_GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);

    //
    // Initialize the UART for console I/O.
    //
    UARTStdioConfig(0, 115200, g_ui32SysClock);
}

//*****************************************************************************
//
// Configure PWM for dead-band generation.
//
//*****************************************************************************

#define PWM1GENA_OFFSET 0xA0
#define PWM2GENA_OFFSET 0xE0
#define PWM1GENB_OFFSET 0xA4
#define PWM2GENB_OFFSET 0xE4
#define PWM1CMPA_OFFSET 0x98
#define PWM1CMPB_OFFSET 0x9C
#define PWM2CMPA_OFFSET 0xD8
#define PWM2CMPB_OFFSET 0xDC

int
main(void)
{
    uint32_t ui32PWMClockRate;

    //
    // Run from the PLL at 120 MHz.
    // Note: SYSCTL_CFG_VCO_240 is a new setting provided in TivaWare 2.2.x and
    // later to better reflect the actual VCO speed due to SYSCTL#22.
    //
    g_ui32SysClock = MAP_SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ |
                                             SYSCTL_OSC_MAIN |
                                             SYSCTL_USE_PLL |
                                             SYSCTL_CFG_VCO_240), 120000000);

    //
    // Initialize the UART.
    //
    ConfigureUART();

    //
    // Display the setup on the console.
    //
    UARTprintf("PWM ->\n");
    UARTprintf("  Module: PWM0\n");
    UARTprintf("  Pin(s): PF2 and PF3\n");
    UARTprintf("  Features: Dead-band Generation\n");
    UARTprintf("  Duty Cycle: 25%% on PF2 and 75%% on PF3\n");
    UARTprintf("  Dead-band Length: 250 cycles\n\n");

    //
    // Enable the GPIO port that is used for the on-board LED.
    //
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPION);

    //
    // Enable the GPIO pin for the LED (PN0) as an output.
    //
    MAP_GPIOPinTypeGPIOOutput(GPIO_PORTN_BASE, GPIO_PIN_0);

    //
    // The PWM peripheral must be enabled for use.
    //
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_PWM0);

    //
    // Enable the GPIO port that is used for the PWM output.
    //
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);

    //
    // Enable the GPIO port that is used for the PWM output.
    //
    MAP_SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOG);


    //
    // Configure the GPIO pad for PWM function on pins PF2 and PF3.
    //
    MAP_GPIOPinConfigure(GPIO_PF2_M0PWM2);
    MAP_GPIOPinConfigure(GPIO_PF3_M0PWM3);
    MAP_GPIOPinTypePWM(GPIO_PORTF_BASE, GPIO_PIN_2);
    MAP_GPIOPinTypePWM(GPIO_PORTF_BASE, GPIO_PIN_3);

    //
    // Configure the GPIO pad for PWM function on pins PF2 and PF3.
    //
    MAP_GPIOPinConfigure(GPIO_PG0_M0PWM4);
    MAP_GPIOPinConfigure(GPIO_PG1_M0PWM5);
    MAP_GPIOPinTypePWM(GPIO_PORTG_BASE, GPIO_PIN_0);
    MAP_GPIOPinTypePWM(GPIO_PORTG_BASE, GPIO_PIN_1);

    //
    // Set the PWM clock to be SysClk / 8.
    //
    MAP_PWMClockSet(PWM0_BASE, PWM_SYSCLK_DIV_8);

    //
    // Use a local variable to store the PWM clock rate which will be
    // 120 MHz / 8 = 15 MHz. This variable will be used to set the
    // PWM generator period.
    //
    ui32PWMClockRate = g_ui32SysClock / 8;

    //
    // Configure PWM2 to count up/down with synchronization.

    MAP_PWMGenConfigure(PWM0_BASE, PWM_GEN_1,
                        PWM_GEN_MODE_UP_DOWN | PWM_GEN_MODE_SYNC);

    MAP_PWMGenConfigure(PWM0_BASE, PWM_GEN_2,
                        PWM_GEN_MODE_UP_DOWN | PWM_GEN_MODE_SYNC);

    // For PWM1GENA, set pin high when counter is zero and reset pin to low
    // when CMPA is matched during count up.

    HWREG(PWM0_BASE + PWM1GENA_OFFSET) = 0x0;
    HWREG(PWM0_BASE + PWM1GENA_OFFSET) = 0x023;

    // For PWM2GENA, set pin high when counter is reloaded and reset pin to low
    // when CMPA is matched during count down.

    HWREG(PWM0_BASE + PWM2GENA_OFFSET) = 0x0;
    HWREG(PWM0_BASE + PWM2GENA_OFFSET) = 0x4C;

    //
    // Set the PWM period to 250Hz.  To calculate the appropriate parameter
    // use the following equation: N = (1 / f) * PWMClk.  Where N is the
    // function parameter, f is the desired frequency, and PWMClk is the
    // PWM clock frequency based on the system clock.
    //
    MAP_PWMGenPeriodSet(PWM0_BASE, PWM_GEN_1, (ui32PWMClockRate / 250));

    MAP_PWMGenPeriodSet(PWM0_BASE, PWM_GEN_2, (ui32PWMClockRate / 250));

    //
    // Set PWM1 CMPA to 40% of half period during count up
    // Set PWM2 CMPA to 10% of half period during count down
    //

    HWREG(PWM0_BASE + PWM1CMPA_OFFSET) = MAP_PWMGenPeriodGet(PWM0_BASE, PWM_GEN_1) * 0.4;
    HWREG(PWM0_BASE + PWM2CMPA_OFFSET) = MAP_PWMGenPeriodGet(PWM0_BASE, PWM_GEN_2) * 0.1;

    PWMSyncUpdate(PWM0_BASE, PWM_GEN_1_BIT | PWM_GEN_2_BIT);
    //
    // Enable the dead-band generation on the PWM0 output signal.
    // These signals will have a 100us gap between the
    // rising and falling edges.
    // For this example the PWM clock rate is 15 MHz, so we will use
    // 150 cycles (1500 cycles / 15MHz = 100us) on both the rising and falling
    // edges of PF2.  Reference the datasheet for more information on PWM
    // dead-band generation.
    //
    MAP_PWMDeadBandEnable(PWM0_BASE, PWM_GEN_1, 1500, 1500);
    MAP_PWMDeadBandEnable(PWM0_BASE, PWM_GEN_2, 1500, 1500);

    //
    // Enable the PWM Out Bit 2 (PF2) and Bit 3 (PF3) output signals.
    //
    MAP_PWMOutputState(PWM0_BASE, PWM_OUT_2_BIT | PWM_OUT_3_BIT, true);
    MAP_PWMOutputState(PWM0_BASE, PWM_OUT_4_BIT | PWM_OUT_5_BIT, true);

    //
    // Enable the PWM generator block.
    //
    MAP_PWMGenEnable(PWM0_BASE, PWM_GEN_1);
    MAP_PWMGenEnable(PWM0_BASE, PWM_GEN_2);


    //
    // Loop forever blinking an LED while the PWM signals are generated.
    //
    while(1)
    {
        //
        // Turn on the LED.
        //
        MAP_GPIOPinWrite(GPIO_PORTN_BASE, GPIO_PIN_0, GPIO_PIN_0);

        //
        // This function provides a means of generating a constant length
        // delay.  The function delay (in cycles) = 3 * parameter.  Delay
        // 0.5 seconds arbitrarily.
        //
        MAP_SysCtlDelay((g_ui32SysClock / 2) / 3);

        //
        // Turn off the LED.
        //
        MAP_GPIOPinWrite(GPIO_PORTN_BASE, GPIO_PIN_0, 0x00);

        //
        // This function provides a means of generating a constant length
        // delay.  The function delay (in cycles) = 3 * parameter.  Delay
        // 0.5 seconds arbitrarily.
        //
        MAP_SysCtlDelay((g_ui32SysClock / 2) / 3);
    }
}