Question

我正在编写一个C程序，该程序控制Raspberry PI上的GPIO状态。我正在使用libgpiod并调用此函数：

gpiod_ctxless_set_value(GPIO_CHIP_NAME, RESET_PIN, 1, false, "some consumer",  NULL, NULL);

但是，函数执行后，引脚立即变为低。如何永久更改？还是至少等到程序退出？

Answer 1

正如@ 0andriy所提到的，出于我的目的，我需要更多的底层函数，而不是无上下文的函数。这是我的带有通用#include <stdio.h> #include <stdlib.h> #include <gpiod.h> #define LED_PIN 28 int main() { struct gpiod_chip *gpiochip; struct gpiod_line *gpioline; int ret; gpiochip = gpiod_chip_open("/dev/gpiochip0"); if (gpiochip == NULL) goto error1; printf("gpiochip open is ok\r\n"); gpioline = gpiod_chip_get_line(gpiochip, TEST_PIN); if (gpioline == NULL) goto error2; printf("gpioline open is ok\r\n"); ret = gpiod_line_request_output(gpioline, "gpio", 0); if (ret != 0) goto error2; printf("request output is ok\r\n"); for (int i = 0; i < 5; i++) { ret = gpiod_line_set_value(gpioline, 1); printf("LED on\r\n"); sleep(1); ret = gpiod_line_set_value(gpioline, 0); printf("LED off\r\n"); sleep(1); } gpiod_line_release(gpioline); error2: gpiod_chip_close(gpiochip); error1: return 0; }函数的测试示例。

as1 <- read.csv(header = T, text = "
da, cat
2016-06-04 04:05:45,A
2016-06-04 04:05:46,B
2016-06-04 04:05:45,C
2016-06-04 04:05:46,D", stringsAsFactors = FALSE)

在C中使用libgpiod永久更改引脚状态

1 个答案: