C++ IS_FUNC_DEFINED函数代码示例

OStack程序员社区-中国程序员成长平台 › 门户 › 编程› C++›C++教程

原作者: [db:作者] 来自: [db:来源] 收藏邀请

本文整理汇总了C++中IS_FUNC_DEFINED函数的典型用法代码示例。如果您正苦于以下问题：C++ IS_FUNC_DEFINED函数的具体用法？C++ IS_FUNC_DEFINED怎么用？C++ IS_FUNC_DEFINED使用的例子？那么恭喜您, 这里精选的函数代码示例或许可以为您提供帮助。

在下文中一共展示了IS_FUNC_DEFINED函数的20个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于我们的系统推荐出更棒的C++代码示例。

示例1: mraa_gpio_close

mraa_result_t
mraa_gpio_close(mraa_gpio_context dev)
{
    mraa_result_t result = MRAA_SUCCESS;

    if (dev == NULL) {
        syslog(LOG_ERR, "gpio: close: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, gpio_close_replace)) {
        return dev->advance_func->gpio_close_replace(dev);
    }


    if (IS_FUNC_DEFINED(dev, gpio_close_pre)) {
        result = dev->advance_func->gpio_close_pre(dev);
    }

    if (dev->value_fp != -1) {
        close(dev->value_fp);
    }
    mraa_gpio_unexport(dev);
    free(dev);
    return result;
}

开发者ID:fboudra，项目名称:mraa，代码行数:26，代码来源:gpio.c

示例2: mraa_i2c_init_internal

static mraa_i2c_context
mraa_i2c_init_internal(mraa_adv_func_t* advance_func, unsigned int bus)
{
    mraa_result_t status = MRAA_SUCCESS;

    if (advance_func == NULL)
        return NULL;

    mraa_i2c_context dev = (mraa_i2c_context) calloc(1, sizeof(struct _i2c));
    if (dev == NULL) {
        syslog(LOG_CRIT, "i2c: Failed to allocate memory for context");
        return NULL;
    }

    dev->advance_func = advance_func;
    dev->busnum = bus;

    if (IS_FUNC_DEFINED(dev, i2c_init_pre)) {
        status = advance_func->i2c_init_pre(bus);
        if (status != MRAA_SUCCESS)
            goto init_internal_cleanup;
    }

    if (IS_FUNC_DEFINED(dev, i2c_init_bus_replace)) {
        status = dev->advance_func->i2c_init_bus_replace(dev);
        if (status != MRAA_SUCCESS)
            goto init_internal_cleanup;
    } else {
        char filepath[32];
        snprintf(filepath, 32, "/dev/i2c-%u", bus);
        if ((dev->fh = open(filepath, O_RDWR)) < 1) {
            syslog(LOG_ERR, "i2c: Failed to open requested i2c port %s", filepath);
            status = MRAA_ERROR_NO_RESOURCES;
            goto init_internal_cleanup;
        }

        if (ioctl(dev->fh, I2C_FUNCS, &dev->funcs) < 0) {
            syslog(LOG_CRIT, "i2c: Failed to get I2C_FUNC map from device");
            dev->funcs = 0;
        }
    }

    if (IS_FUNC_DEFINED(dev, i2c_init_post)) {
        status = dev->advance_func->i2c_init_post(dev);
        if (status != MRAA_SUCCESS)
            goto init_internal_cleanup;
    }


init_internal_cleanup:
    if (status == MRAA_SUCCESS) {
        return dev;
    } else {
        if (dev != NULL)
            free(dev);
        return NULL;
   }
}

开发者ID:Chechare，项目名称:mraa，代码行数:58，代码来源:i2c.c

示例3: mraa_gpio_mode

mraa_result_t
mraa_gpio_mode(mraa_gpio_context dev, mraa_gpio_mode_t mode)
{
    if (IS_FUNC_DEFINED(dev, gpio_mode_replace))
        return dev->advance_func->gpio_mode_replace(dev, mode);

    if (IS_FUNC_DEFINED(dev, gpio_mode_pre)) {
        mraa_result_t pre_ret = (dev->advance_func->gpio_mode_pre(dev, mode));
        if (pre_ret != MRAA_SUCCESS)
            return pre_ret;
    }

    if (dev->value_fp != -1) {
        close(dev->value_fp);
        dev->value_fp = -1;
    }

    char filepath[MAX_SIZE];
    snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/drive", dev->pin);

    int drive = open(filepath, O_WRONLY);
    if (drive == -1) {
        syslog(LOG_ERR, "gpio: Failed to open drive for writing");
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    char bu[MAX_SIZE];
    int length;
    switch (mode) {
        case MRAA_GPIO_STRONG:
            length = snprintf(bu, sizeof(bu), "strong");
            break;
        case MRAA_GPIO_PULLUP:
            length = snprintf(bu, sizeof(bu), "pullup");
            break;
        case MRAA_GPIO_PULLDOWN:
            length = snprintf(bu, sizeof(bu), "pulldown");
            break;
        case MRAA_GPIO_HIZ:
            length = snprintf(bu, sizeof(bu), "hiz");
            break;
        default:
            close(drive);
            return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
    }
    if (write(drive, bu, length * sizeof(char)) == -1) {
        syslog(LOG_ERR, "gpio: Failed to write to drive mode");
        close(drive);
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    close(drive);
    if (IS_FUNC_DEFINED(dev, gpio_mode_post))
        return dev->advance_func->gpio_mode_post(dev, mode);
    return MRAA_SUCCESS;
}

开发者ID:anonymouse64，项目名称:mraa，代码行数:56，代码来源:gpio.c

示例4: mraa_pwm_enable

mraa_result_t
mraa_pwm_enable(mraa_pwm_context dev, int enable)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: enable: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_enable_replace)) {
        return dev->advance_func->pwm_enable_replace(dev, enable);
    }

    char bu[MAX_SIZE];
    snprintf(bu, MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/enable", dev->chipid, dev->pin);

    int enable_f = open(bu, O_RDWR);

    if (enable_f == -1) {
        syslog(LOG_ERR, "pwm_enable: pwm%i: Failed to open enable for writing: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    char out[2];
    int size = snprintf(out, sizeof(out), "%d", enable);
    if (write(enable_f, out, size * sizeof(char)) == -1) {
        syslog(LOG_ERR, "pwm_enable: pwm%i: Failed to write to enable: %s", dev->pin, strerror(errno));
        close(enable_f);
        return MRAA_ERROR_UNSPECIFIED;
    }
    close(enable_f);
    return MRAA_SUCCESS;
}

开发者ID:cocasema，项目名称:mraa，代码行数:31，代码来源:pwm.c

示例5: mraa_aio_init_internal

static mraa_aio_context
mraa_aio_init_internal(mraa_adv_func_t* func_table, int aio)
{
    mraa_aio_context dev = calloc(1, sizeof(struct _aio));
    if (dev == NULL) {
        return NULL;
    }
    dev->advance_func = func_table;

    if (IS_FUNC_DEFINED(dev, aio_init_internal_replace)) {
        if (dev->advance_func->aio_init_internal_replace(dev, aio) == MRAA_SUCCESS) {
            return dev;
        }
        free(dev);
        return NULL;
    }

    // Open valid  analog input file and get the pointer.
    if (MRAA_SUCCESS != aio_get_valid_fp(dev)) {
        free(dev);
        return NULL;
    }

    return dev;
}

开发者ID:cocasema，项目名称:mraa，代码行数:25，代码来源:aio.c

示例6: aio_get_valid_fp

static mraa_result_t
aio_get_valid_fp(mraa_aio_context dev)
{
    if (dev == NULL) {
        syslog(LOG_ERR, "aio: get_valid_fp: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, aio_get_valid_fp)) {
        return dev->advance_func->aio_get_valid_fp(dev);
    }

    char file_path[64] = "";

    // Open file Analog device input channel raw voltage file for reading.
    snprintf(file_path, 64, "/sys/bus/iio/devices/iio:device0/in_voltage%d_raw", dev->channel);

    dev->adc_in_fp = open(file_path, O_RDONLY);
    if (dev->adc_in_fp == -1) {
        syslog(LOG_ERR, "aio: Failed to open input raw file %s for reading!", file_path);
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    return MRAA_SUCCESS;
}

开发者ID:KurtE，项目名称:mraa，代码行数:25，代码来源:aio.c

示例7: mraa_pwm_enable

mraa_result_t
mraa_pwm_enable(mraa_pwm_context dev, int enable)
{
	if (IS_FUNC_DEFINED(dev, pwm_enable_replace)) {
        return dev->advance_func->pwm_enable_replace(dev, enable);
    }
    int status;
    if (enable != 0) {
        status = 1;
    } else {
        status = enable;
    }
    char bu[MAX_SIZE];
    snprintf(bu, MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/enable", dev->chipid, dev->pin);

    int enable_f = open(bu, O_RDWR);

    if (enable_f == -1) {
        syslog(LOG_ERR, "pwm: Failed to open enable for writing");
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    char out[2];
    int size = snprintf(out, sizeof(out), "%d", enable);
    if (write(enable_f, out, size * sizeof(char)) == -1) {
        syslog(LOG_ERR, "pwm: Failed to write to enable");
        close(enable_f);
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    close(enable_f);
    return MRAA_SUCCESS;
}

开发者ID:Sayter99，项目名称:mraa，代码行数:31，代码来源:pwm.c

示例8: mraa_pwm_read_duty

static int
mraa_pwm_read_duty(mraa_pwm_context dev)
{
	if (IS_FUNC_DEFINED(dev, pwm_read_duty_replace)) {
        return dev->advance_func->pwm_read_duty_replace(dev);
    }
    if (dev->duty_fp == -1) {
        if (mraa_pwm_setup_duty_fp(dev) == 1) {
            return MRAA_ERROR_INVALID_HANDLE;
        }
    } else {
        lseek(dev->duty_fp, 0, SEEK_SET);
    }
    off_t size = lseek(dev->duty_fp, 0, SEEK_END);
    lseek(dev->duty_fp, 0, SEEK_SET);
    char output[MAX_SIZE];
    ssize_t rb = read(dev->duty_fp, output, size + 1);
    if (rb < 0) {
        syslog(LOG_ERR, "pwm: Error in reading duty");
        return -1;
    }

    char* endptr;
    long int ret = strtol(output, &endptr, 10);
    if ('\0' != *endptr && '\n' != *endptr) {
        syslog(LOG_ERR, "pwm: Error in string converstion");
        return -1;
    } else if (ret > INT_MAX || ret < INT_MIN) {
        syslog(LOG_ERR, "pwm: Number is invalid");
        return -1;
    }
    return (int) ret;
}

开发者ID:Sayter99，项目名称:mraa，代码行数:33，代码来源:pwm.c

示例9: mraa_uart_set_non_blocking

mraa_result_t
mraa_uart_set_non_blocking(mraa_uart_context dev, mraa_boolean_t nonblock)
{
    if (!dev) {
        syslog(LOG_ERR, "uart: non_blocking: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, uart_set_non_blocking_replace)) {
        return dev->advance_func->uart_set_non_blocking_replace(dev, nonblock);
    }

    // get current flags
    int flags = fcntl(dev->fd, F_GETFL);

    // update flags with new blocking state according to nonblock bool
    if (nonblock) {
        flags |= O_NONBLOCK;
    } else {
        flags &= ~O_NONBLOCK;
    }

    // set new flags
    if (fcntl(dev->fd, F_SETFL, flags) < 0) {
        syslog(LOG_ERR, "uart%i: non_blocking: failed changing fd blocking state: %s", dev->index, strerror(errno));
        return MRAA_ERROR_UNSPECIFIED;
    }

    return MRAA_SUCCESS;
}

开发者ID:jontrulson，项目名称:mraa，代码行数:30，代码来源:uart.c

示例10: mraa_uart_set_timeout

mraa_result_t
mraa_uart_set_timeout(mraa_uart_context dev, int read, int write, int interchar)
{
    if (!dev) {
        syslog(LOG_ERR, "uart: set_timeout: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, uart_set_timeout_replace)) {
        return dev->advance_func->uart_set_timeout_replace(dev, read, write, interchar);
    }

    struct termios termio;
    // get current modes
    if (tcgetattr(dev->fd, &termio)) {
        syslog(LOG_ERR, "uart%i: set_timeout: tcgetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    if (read > 0) {
        read = read / 100;
        if (read == 0)
            read = 1;
    }
    termio.c_lflag &= ~ICANON; /* Set non-canonical mode */
    termio.c_cc[VTIME] = read; /* Set timeout in tenth seconds */
    if (tcsetattr(dev->fd, TCSANOW, &termio) < 0) {
        syslog(LOG_ERR, "uart%i: set_timeout: tcsetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_FEATURE_NOT_SUPPORTED;
    }

    return MRAA_SUCCESS;
}

开发者ID:jontrulson，项目名称:mraa，代码行数:32，代码来源:uart.c

示例11: mraa_gpio_init

mraa_gpio_context
mraa_gpio_init(int pin)
{
    mraa_board_t* board = plat;

    if (board == NULL) {
        syslog(LOG_ERR, "gpio%i: init: platform not initialised", pin);
        return NULL;
    }

    if (mraa_is_sub_platform_id(pin)) {
        syslog(LOG_NOTICE, "gpio%i: init: Using sub platform", pin);
        board = board->sub_platform;
        if (board == NULL) {
            syslog(LOG_ERR, "gpio%i: init: Sub platform not initialised", pin);
            return NULL;
        }
        pin = mraa_get_sub_platform_index(pin);
    }

    if (board->chardev_capable) {
        int pins[1] = { pin };
        return mraa_gpio_init_multi(pins, 1);
    }

    if (pin < 0 || pin >= board->phy_pin_count) {
        syslog(LOG_ERR, "gpio: init: pin %i beyond platform pin count (%i)",
               pin, board->phy_pin_count);
        return NULL;
    }
    if (board->pins[pin].capabilities.gpio != 1) {
        syslog(LOG_ERR, "gpio: init: pin %i not capable of gpio", pin);
        return NULL;
    }
    if (board->pins[pin].gpio.mux_total > 0) {
        if (mraa_setup_mux_mapped(board->pins[pin].gpio) != MRAA_SUCCESS) {
            syslog(LOG_ERR, "gpio%i: init: unable to setup muxes", pin);
            return NULL;
        }
    }

    mraa_gpio_context r = mraa_gpio_init_internal(board->adv_func, board->pins[pin].gpio.pinmap);

    if (r == NULL) {
        return NULL;
    }

    if (r->phy_pin == -1)
        r->phy_pin = pin;

    if (IS_FUNC_DEFINED(r, gpio_init_post)) {
        mraa_result_t ret = r->advance_func->gpio_init_post(r);
        if (ret != MRAA_SUCCESS) {
            free(r);
            return NULL;
        }
    }

    return r;
}

开发者ID:zgramana，项目名称:mraa，代码行数:60，代码来源:gpio.c

示例12: mraa_spi_frequency

mraa_result_t
mraa_spi_frequency(mraa_spi_context dev, int hz)
{
    if (dev == NULL) {
        syslog(LOG_ERR, "spi: frequency: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, spi_frequency_replace)) {
        return dev->advance_func->spi_frequency_replace(dev, hz);
    }

    int speed = 0;
    dev->clock = hz;
    if (ioctl(dev->devfd, SPI_IOC_RD_MAX_SPEED_HZ, &speed) != -1) {
	if (speed < hz) {
            // We wanted to never go higher than SPI_IOC_RD_MAX_SPEED_HZ but it
            // seems a bunch of drivers don't have this set to the actual max
            // so we only complain about it
            // dev->clock = speed;
            syslog(LOG_NOTICE, "spi: Selected speed (%d Hz) is higher than the kernel max allowed speed (%lu Hz)", hz, SPI_IOC_RD_MAX_SPEED_HZ);
        }
    }
    return MRAA_SUCCESS;
}

开发者ID:KurtE，项目名称:mraa，代码行数:25，代码来源:spi.c

示例13: mraa_pwm_write_duty

static mraa_result_t
mraa_pwm_write_duty(mraa_pwm_context dev, int duty)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: write_duty: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_write_replace)) {
        return dev->advance_func->pwm_write_replace(dev, duty);
    }
    if (dev->duty_fp == -1) {
        if (mraa_pwm_setup_duty_fp(dev) == 1) {
            syslog(LOG_ERR, "pwm%i write_duty: Failed to open duty_cycle for writing: %s", dev->pin, strerror(errno));
            return MRAA_ERROR_INVALID_RESOURCE;
        }
    }
    char bu[64];
    int length = sprintf(bu, "%d", duty);
    if (write(dev->duty_fp, bu, length * sizeof(char)) == -1)
    {
        syslog(LOG_ERR, "pwm%i write_duty: Failed to write to duty_cycle: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    return MRAA_SUCCESS;
}

开发者ID:Hbrinj，项目名称:mraa，代码行数:26，代码来源:pwm.c

示例14: mraa_pwm_write_period

static mraa_result_t
mraa_pwm_write_period(mraa_pwm_context dev, int period)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: write_period: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_period_replace)) {
        mraa_result_t result = dev->advance_func->pwm_period_replace(dev, period);
        if (result == MRAA_SUCCESS) {
            dev->period = period;
        }
        return result;
    }
    char bu[MAX_SIZE];
    snprintf(bu, MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/period", dev->chipid, dev->pin);

    int period_f = open(bu, O_RDWR);
    if (period_f == -1) {
        syslog(LOG_ERR, "pwm%i write_period: Failed to open period for writing: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    char out[MAX_SIZE];
    int length = snprintf(out, MAX_SIZE, "%d", period);
    if (write(period_f, out, length * sizeof(char)) == -1) {
        close(period_f);
        syslog(LOG_ERR, "pwm%i write_period: Failed to write to period: %s", dev->pin, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    close(period_f);
    dev->period = period;
    return MRAA_SUCCESS;
}

开发者ID:Hbrinj，项目名称:mraa，代码行数:35，代码来源:pwm.c

示例15: mraa_uart_set_baudrate

mraa_result_t
mraa_uart_set_baudrate(mraa_uart_context dev, unsigned int baud)
{
    if (!dev) {
        syslog(LOG_ERR, "uart: set_baudrate: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, uart_set_baudrate_replace)) {
        return dev->advance_func->uart_set_baudrate_replace(dev, baud);
    }

    struct termios termio;
    if (tcgetattr(dev->fd, &termio)) {
        syslog(LOG_ERR, "uart%i: set_baudrate: tcgetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_INVALID_RESOURCE;
    }

    // set our baud rates
    speed_t speed = uint2speed(baud);
    if (speed == B0)
    {
        syslog(LOG_ERR, "uart%i: set_baudrate: invalid baudrate: %i", dev->index, baud);
        return MRAA_ERROR_INVALID_PARAMETER;
    }
    cfsetispeed(&termio, speed);
    cfsetospeed(&termio, speed);

    // make it so
    if (tcsetattr(dev->fd, TCSAFLUSH, &termio) < 0) {
        syslog(LOG_ERR, "uart%i: set_baudrate: tcsetattr() failed: %s", dev->index, strerror(errno));
        return MRAA_ERROR_FEATURE_NOT_SUPPORTED;
    }
    return MRAA_SUCCESS;
}

开发者ID:jontrulson，项目名称:mraa，代码行数:35，代码来源:uart.c

示例16: mraa_gpio_read

int
mraa_gpio_read(mraa_gpio_context dev)
{
    if (dev == NULL)
        return -1;

    if (IS_FUNC_DEFINED(dev, gpio_read_replace))
        return dev->advance_func->gpio_read_replace(dev);

    if (dev->mmap_read != NULL)
        return dev->mmap_read(dev);

    if (dev->value_fp == -1) {
        if (mraa_gpio_get_valfp(dev) != MRAA_SUCCESS) {
            syslog(LOG_ERR, "gpio: Failed to get value file pointer");
            return -1;
        }
    } else {
        // if value_fp is new this is pointless
        lseek(dev->value_fp, 0, SEEK_SET);
    }
    char bu[2];
    if (read(dev->value_fp, bu, 2 * sizeof(char)) != 2) {
        syslog(LOG_ERR, "gpio: Failed to read a sensible value from sysfs");
        return -1;
    }
    lseek(dev->value_fp, 0, SEEK_SET);

    return (int) strtol(bu, NULL, 10);
}

开发者ID:anonymouse64，项目名称:mraa，代码行数:30，代码来源:gpio.c

示例17: mraa_spi_transfer_buf_word

mraa_result_t
mraa_spi_transfer_buf_word(mraa_spi_context dev, uint16_t* data, uint16_t* rxbuf, int length)
{
    if (dev == NULL) {
        syslog(LOG_ERR, "spi: transfer_buf_word: context is invalid");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, spi_transfer_buf_word_replace)) {
        return dev->advance_func->spi_transfer_buf_word_replace(dev, data, rxbuf, length);
    }

    struct spi_ioc_transfer msg;
    memset(&msg, 0, sizeof(msg));

    msg.tx_buf = (unsigned long) data;
    msg.rx_buf = (unsigned long) rxbuf;
    msg.speed_hz = dev->clock;
    msg.bits_per_word = dev->bpw;
    msg.delay_usecs = 0;
    msg.len = length;
    if (ioctl(dev->devfd, SPI_IOC_MESSAGE(1), &msg) < 0) {
        syslog(LOG_ERR, "spi: Failed to perform dev transfer");
        return MRAA_ERROR_INVALID_RESOURCE;
    }
    return MRAA_SUCCESS;
}

开发者ID:KurtE，项目名称:mraa，代码行数:27，代码来源:spi.c

示例18: mraa_spi_write_word

int
mraa_spi_write_word(mraa_spi_context dev, uint16_t data)
{
    if (dev == NULL) {
        syslog(LOG_ERR, "spi: write_word: context is invalid");
        return -1;
    }

    if (IS_FUNC_DEFINED(dev, spi_write_word_replace)) {
        return dev->advance_func->spi_write_word_replace(dev, data);
    }

    struct spi_ioc_transfer msg;
    memset(&msg, 0, sizeof(msg));

    uint16_t length = 2;

    uint16_t recv = 0;
    msg.tx_buf = (unsigned long) &data;
    msg.rx_buf = (unsigned long) &recv;
    msg.speed_hz = dev->clock;
    msg.bits_per_word = dev->bpw;
    msg.delay_usecs = 0;
    msg.len = length;
    if (ioctl(dev->devfd, SPI_IOC_MESSAGE(1), &msg) < 0) {
        syslog(LOG_ERR, "spi: Failed to perform dev transfer");
        return -1;
    }
    return (int) recv;
}

开发者ID:KurtE，项目名称:mraa，代码行数:30，代码来源:spi.c

示例19: mraa_pwm_write

mraa_result_t
mraa_pwm_write(mraa_pwm_context dev, float percentage)
{
    if (!dev) {
        syslog(LOG_ERR, "pwm: write: context is NULL");
        return MRAA_ERROR_INVALID_HANDLE;
    }

    if (IS_FUNC_DEFINED(dev, pwm_write_pre)) {
        if (dev->advance_func->pwm_write_pre(dev, percentage) != MRAA_SUCCESS) {
            syslog(LOG_ERR, "mraa_pwm_write (pwm%i): pwm_write_pre failed, see syslog", dev->pin);
            return MRAA_ERROR_UNSPECIFIED;
        }
    }

    if (dev->period == -1) {
        if (mraa_pwm_read_period(dev) <= 0)
            return MRAA_ERROR_NO_DATA_AVAILABLE;
    }

    if (percentage > 1.0f) {
        syslog(LOG_WARNING, "pwm_write: %i%% entered, defaulting to 100%%",(int) percentage * 100);
        return mraa_pwm_write_duty(dev, dev->period);
    }
    return mraa_pwm_write_duty(dev, percentage * dev->period);
}

开发者ID:Hbrinj，项目名称:mraa，代码行数:26，代码来源:pwm.c

示例20: mraa_i2c_frequency

mraa_result_t
mraa_i2c_frequency(mraa_i2c_context dev, mraa_i2c_mode_t mode)
{
    if (IS_FUNC_DEFINED(dev, i2c_set_frequency_replace)) {
        return dev->advance_func->i2c_set_frequency_replace(dev, mode);
    }
    return MRAA_ERROR_FEATURE_NOT_SUPPORTED;
}

开发者ID:Chechare，项目名称:mraa，代码行数:8，代码来源:i2c.c

注：本文中的IS_FUNC_DEFINED函数示例由纯净天空整理自Github/MSDocs等源码及文档管理平台，相关代码片段筛选自各路编程大神贡献的开源项目，源码版权归原作者所有，传播和使用请参考对应项目的License；未经允许，请勿转载。

鲜花

握手

雷人

路过

鸡蛋

该文章已有0人参与评论

请发表评论

全部评论

专题导读

More+

10-27 六六分期app的软件客服如何联系？(六六分期

11-06 可心卡盟:win10系统火狐flash插件崩溃怎么

11-06 亲亲特价:怎么删除回收站图标

11-06 济南大学虚拟社区:鲁大师节能降温的具体办

11-06 xlueops.exe:无线网络安装向导

11-06 女斗合众国:win7系统cf与主机连接不稳定怎

11-06 0xc000022-[cf烟雾头]cf怎么调烟雾头

11-06 qizideyouhuo:应用程序无法正常启动0xc0000

11-06 ipz-185:win7系统vcf文件怎么打开

11-06 傻哥蹦迪:win10系统s4怎么打开usb调试

11-06 八神浩树gtaste:回收站清空了怎么恢复

11-06 妖尾之黑色守护:win10系统电脑没有1440x900

11-06 校园至尊魔王小说:win7系统浏览网页时字体

11-06 女斗合众国:win10系统访问共享文件夹提示请

11-06 tokyo hot n0654:恢复win7系统默认字体一招

11-06 雨酷仙境:设置win7系统转移临时文件夹腾出

11-06 阿穆纳伊之杖:win7系统开始菜单在右边还原

11-06 tunespotting:win10系统火狐flash插件总是

11-06 甘尔葛分析师：计谋网站seo关键词暴涨有什

11-06 蔡贵霖: 计谋网站seo关键词暴涨有什么秘密

11-06 博益网首页:ao3网页版进入不了解决方法

11-06 漏斗子专栏: 网站数据分析小白易懂精华篇

11-06 见证双虹怎么做:win7系统开启telnet命令的

11-06 颾狐蝶蜋:系统资源不足无法完成请求的服务

11-06 国光中学校歌:提交网站到alexa查询详细步骤

11-06 西安有情天:静态网页和动态网页的区别

11-06 红木雅尚斋:外部链接构造对网站的好处

11-06 前官礼遇：防止域名劫持–增强域安全性的10

11-06 密传二转答案: 中文分词算法有哪些

11-06 金泉家园邮编:百度快照劫持的表现及应对方

C++ IS_G4X函数代码示例发布时间：2022-05-30

C++ IS_FUNCTIONAL_STATE函数代码示例发布时间：2022-05-30

剪的笔顺,诠释剪的笔画,认识剪的部首

1 六六分期app的软件客服如何联系？(六六分期

六六分期app的软件客服如何联系？不知道吗？加qq群【895510560】即可！标题：六六分期

阅读：19222|2023-10-27

2 可心卡盟:win10系统火狐flash插件崩溃怎么

今天小编告诉大家如何处理win10系统火狐flash插件总是崩溃的问题，可能很多用户都不知

阅读：9996|2022-11-06

3 亲亲特价:怎么删除回收站图标

今天小编告诉大家如何对win10系统删除桌面回收站图标进行设置，可能很多用户都不知道

阅读：8331|2022-11-06

4 济南大学虚拟社区:鲁大师节能降温的具体办

今天小编告诉大家如何对win10系统电脑设置节能降温的设置方法，想必大家都遇到过需要

阅读：8700|2022-11-06

5 xlueops.exe:无线网络安装向导

我们在使用xp系统的过程中,经常需要对xp系统无线网络安装向导设置进行设置，可能很多

阅读：8644|2022-11-06

6 女斗合众国:win7系统cf与主机连接不稳定怎

今天小编告诉大家如何处理win7系统玩cf老是与主机连接不稳定的问题，可能很多用户都不

阅读：9666|2022-11-06

7 0xc000022-[cf烟雾头]cf怎么调烟雾头

电脑对日常生活的重要性小编就不多说了，可是一旦碰到win7系统设置cf烟雾头的问题，很

阅读：8630|2022-11-06

8 qizideyouhuo:应用程序无法正常启动0xc0000

我们在日常使用电脑的时候，有的小伙伴们可能在打开应用的时候会遇见提示应用程序无法

阅读：8004|2022-11-06

9 ipz-185:win7系统vcf文件怎么打开

今天小编告诉大家如何对win7系统打开vcf文件进行设置，可能很多用户都不知道怎么对win

阅读：8664|2022-11-06

10 傻哥蹦迪:win10系统s4怎么打开usb调试

今天小编告诉大家如何对win10系统s4开启USB调试模式进行设置，可能很多用户都不知道怎

阅读：7539|2022-11-06

客服电话

电子邮件

C++ IS_FUNC_DEFINED函数代码示例

示例1: mraa_gpio_close

示例2: mraa_i2c_init_internal

示例3: mraa_gpio_mode

示例4: mraa_pwm_enable

示例5: mraa_aio_init_internal

示例6: aio_get_valid_fp

示例7: mraa_pwm_enable

示例8: mraa_pwm_read_duty

示例9: mraa_uart_set_non_blocking

示例10: mraa_uart_set_timeout

示例11: mraa_gpio_init

示例12: mraa_spi_frequency

示例13: mraa_pwm_write_duty

示例14: mraa_pwm_write_period

示例15: mraa_uart_set_baudrate

示例16: mraa_gpio_read

示例17: mraa_spi_transfer_buf_word

示例18: mraa_spi_write_word

示例19: mraa_pwm_write

示例20: mraa_i2c_frequency

请发表评论

全部评论

上一篇：

下一篇：

delphi验证码识别之如何识别高级验证码

librespeed/speedtest: Self-hosted Speedt

avehtari/BDA_m_demos: Bayesian Data Anal

四维彩超怎么看性别？四维看男孩女孩诀窍

medfreeman/markdown-it-toc-and-anchor: m

剪的笔顺,诠释剪的笔画,认识剪的部首

六六分期app的软件客服如何联系？(六六分期

florent37/ViewAnimator: A fluent Android

florent37/Shrine-MaterialDesign2: implem

CVE-2020-36276

SimpleSoftwareIO/simple-sms: Send and re

关于我们

产品与服务

解决方案

139-2527-9053