/**
* @file bbb_pin.c
- * @purpose Implementation of BBB pin control functions and structures
+ * @brief Implementation of BBB pin control functions and structures
+ * On non-beaglebone (actually non-arm) platforms, this code is disabled.
* THIS CODE IS NOT THREADSAFE
*/
+#define _BBB_PIN_SRC
#include "bbb_pin.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
-#include <ctype.h>
#include "options.h"
/**
*/
typedef struct
{
+ bool initialised;
int fd_value;
int fd_direction;
} GPIO_Pin;
*/
typedef struct
{
+ bool initialised;
int fd_value;
} ADC_Pin;
*/
typedef struct
{
+ bool initialised;
int fd_run;
FILE * file_duty;
FILE * file_period;
/** Array of PWM pins **/
static PWM_Pin g_pwm[PWM_NUM_PINS] = {{0}};
-static char g_buffer[BUFSIZ] = "";
+static char g_buffer[BUFSIZ] = {0};
-#define GPIO_LUT_SIZE 93
-#define GPIO_INDEX_SIZE 128
-
-/**
- * A lookup table from header number to GPIO pin number.
- * e.g P8_13 is g_gpio_lut[0*46+13] = g_gpio_lut[13]
- * e.g P9_13 is g_gpio_lut[1*46+13] = g_gpio_lut[59]
- *
- * Where the returned value is 0, there is no GPIO pin
- * at that location.
+/**
+ * Maps a GPIO number to an index into g_gpio (only for use in bbb_pin.c)
+ * If there is no index for that GPIO number, 128 is returned.
*/
-const unsigned char g_gpio_lut[GPIO_LUT_SIZE] = {
- 0, 0, 0, 0, 0, 0, 0, 66, 67, 69, 68, 45, 44, 23,
- 26, 47, 46, 27, 65, 22, 0, 0, 0, 0, 0, 0, 61, 86,
- 88, 87, 89, 10, 11, 9, 81, 8, 80, 78, 79, 76, 77, 74,
- 75, 72, 73, 70, 71, 0, 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 30, 60, 31, 50, 48, 51, 5, 4, 0, 0, 3, 2, 49,
- 15, 117, 14, 115, 0, 0, 112, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0, 0
+const unsigned char g_pin_gpio_to_index[GPIO_MAX_NUMBER+1] = {
+ 128, 128, 128, 128, 0, 1, 128, 128, 2, 3, 4, 5, 128, 128,
+ 6, 7, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 8, 9,
+ 128, 128, 10, 11, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 12, 13, 14, 15, 16, 17, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 18, 19, 128, 128, 128, 20, 21, 22, 23, 24,
+ 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 128, 128,
+ 128, 128, 37, 38, 39, 40, 128, 128, 128, 128, 128, 128, 128, 128,
+ 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
+ 41, 128, 128, 42
};
/**
- * Converts GPIO number to index into g_gpio, or 128 if no map.
+ * Maps an index in g_gpio to the corresponding GPIO number.
*/
-const unsigned char g_gpio_index[GPIO_INDEX_SIZE] = {
- 128, 128, 0, 1, 2, 3, 128, 128, 4, 5, 6, 7, 128, 128,
- 8, 9, 128, 128, 128, 128, 128, 128, 10, 11, 128, 128, 12, 13,
- 128, 128, 14, 15, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
- 128, 128, 16, 17, 18, 19, 20, 21, 22, 23, 128, 128, 128, 128,
- 128, 128, 128, 128, 24, 25, 128, 128, 128, 26, 27, 28, 29, 30,
- 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 128, 128,
- 128, 128, 43, 44, 45, 46, 128, 128, 128, 128, 128, 128, 128, 128,
- 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
- 47, 128, 128, 48, 128, 49, 128, 128, 128, 128, 128, 128, 128, 128,
- 128, 128
+const unsigned char g_pin_index_to_gpio[GPIO_NUM_PINS] = {
+ 4, 5, 8, 9, 10, 11, 14, 15, 26, 27, 30, 31, 44, 45,
+ 46, 47, 48, 49, 60, 61, 65, 66, 67, 68, 69, 70, 71, 72,
+ 73, 74, 75, 76, 77, 78, 79, 80, 81, 86, 87, 88, 89, 112,
+ 115
};
/**
* Export a GPIO pin and open the file descriptors
+ * @param pin The GPIO number to be exported
+ * @return true on success, false otherwise
*/
-void GPIO_Export(int pin)
+bool GPIO_Export(int pin)
{
- if (pin < 0 || pin >= GPIO_INDEX_SIZE || g_gpio_index[pin] == 128)
+ if (pin < 0 || pin > GPIO_MAX_NUMBER || g_pin_gpio_to_index[pin] == 128)
{
- Abort("Not a useable pin (number %d)", pin);
+ AbortBool("Not a useable pin number: %d", pin);
+ }
+
+ GPIO_Pin *gpio = &g_gpio[g_pin_gpio_to_index[pin]];
+ if (gpio->initialised)
+ {
+ Log(LOGNOTE, "GPIO %d already initialised.", pin);
+ return true;
}
// Export the pin
sprintf(g_buffer, "%s/export", GPIO_DEVICE_PATH);
- FILE * export = fopen(g_buffer, "w");
- if (export == NULL)
+ FILE * file_export = fopen(g_buffer, "w");
+ if (file_export == NULL)
{
- Abort("Couldn't open %s to export GPIO pin %d - %s", g_buffer, pin, strerror(errno));
+ AbortBool("Couldn't open %s to export GPIO pin %d - %s", g_buffer, pin, strerror(errno));
}
-
- fprintf(export, "%d", pin);
- fclose(export);
+ fprintf(file_export, "%d", pin);
+ fclose(file_export);
- GPIO_Pin *gpio = &g_gpio[g_gpio_index[pin]];
// Setup direction file descriptor
sprintf(g_buffer, "%s/gpio%d/direction", GPIO_DEVICE_PATH, pin);
gpio->fd_direction = open(g_buffer, O_RDWR);
if (gpio->fd_direction < 0)
{
- Abort("Couldn't open %s for GPIO pin %d - %s", g_buffer, pin, strerror(errno));
+ AbortBool("Couldn't open %s for GPIO pin %d - %s", g_buffer, pin, strerror(errno));
}
-
// Setup value file descriptor
sprintf(g_buffer, "%s/gpio%d/value", GPIO_DEVICE_PATH, pin);
gpio->fd_value = open(g_buffer, O_RDWR);
if (gpio->fd_value < 0)
{
- Abort("Couldn't open %s for GPIO pin %d - %s", g_buffer, pin, strerror(errno));
+ close(gpio->fd_direction);
+ AbortBool("Couldn't open %s for GPIO pin %d - %s", g_buffer, pin, strerror(errno));
}
+ gpio->initialised = true;
Log(LOGDEBUG, "Exported GPIO%d", pin);
- //sleep(1);
+ return true;
}
/**
* Unexport a GPIO pin and close its' file descriptors
+ * @param pin The GPIO number to be unexported
*/
void GPIO_Unexport(int pin)
{
+ if (pin < 0 || pin > GPIO_MAX_NUMBER || g_pin_gpio_to_index[pin] == 128)
+ {
+ Abort("Not a useable pin number: %d", pin);
+ }
- if (pin < 0 || pin >= GPIO_INDEX_SIZE || g_gpio_index[pin] == 128)
+ GPIO_Pin *gpio = &g_gpio[g_pin_gpio_to_index[pin]];
+ if (!gpio->initialised)
{
- Abort("Not a useable pin (number %d)", pin);
+ Abort("GPIO %d is already uninitialised", pin);
}
- GPIO_Pin *gpio = &g_gpio[g_gpio_index[pin]];
// Close file descriptors
close(gpio->fd_value);
close(gpio->fd_direction);
+ // Uninitialise this one
+ gpio->initialised = false;
// Unexport the pin
-
if (g_buffer[0] == '\0')
sprintf(g_buffer, "%s/unexport", GPIO_DEVICE_PATH);
- FILE * export = fopen(g_buffer, "w");
- if (export == NULL)
+ FILE * file_export = fopen(g_buffer, "w");
+ if (file_export == NULL)
{
Abort("Couldn't open %s to export GPIO pin %d - %s", g_buffer, pin, strerror(errno));
}
- fprintf(export, "%d", pin);
- fclose(export);
+ fprintf(file_export, "%d", pin);
+ fclose(file_export);
}
-
-
-
/**
- * Export all PWM pins and open file descriptors
- * @param pin - The pin number
+ * Initialise all PWM pins and open file descriptors
+ * @param pin - The sysfs pin number
+ * @return true if exported, false otherwise
*/
-void PWM_Export(int pin)
+bool PWM_Export(int pin)
{
- if (pin < 0 || pin > PWM_NUM_PINS)
+ //goto would make this easier...
+ if (pin < 0 || pin >= PWM_NUM_PINS)
{
- Abort("Invalid pin number %d", pin);
+ AbortBool("Invalid PWM pin %d specified.", pin);
}
-
- // Export the pin
+
+ PWM_Pin *pwm = &g_pwm[pin];
+ if (pwm->initialised)
+ {
+ Log(LOGNOTE, "PWM %d already exported.", pin);
+ return true;
+ }
+
+ // Try export the pin, doesn't matter if it's already exported.
sprintf(g_buffer, "%s/export", PWM_DEVICE_PATH);
- FILE * export = fopen(g_buffer, "w");
- if (export == NULL)
+ FILE * file_export = fopen(g_buffer, "w");
+ if (file_export == NULL)
{
- Abort("Couldn't open %s to export PWM pin %d - %s", g_buffer, pin, strerror(errno));
+ AbortBool("Couldn't open %s to export PWM pin %d - %s",
+ g_buffer, pin, strerror(errno));
}
-
- fprintf(export, "%d\n", pin);
- fclose(export);
+ fprintf(file_export, "%d\n", pin);
+ fclose(file_export);
// Open file descriptors
sprintf(g_buffer, "%s/pwm%d/run", PWM_DEVICE_PATH, pin);
- g_pwm[pin].fd_run = open(g_buffer, O_WRONLY);
- if (g_pwm[pin].fd_run < 0)
+ pwm->fd_run = open(g_buffer, O_WRONLY);
+ if (pwm->fd_run < 0)
{
- Abort("Couldn't open %s for PWM pin %d - %s", g_buffer, pin, strerror(errno));
+ AbortBool("Couldn't open %s for PWM%d - %s", g_buffer, pin, strerror(errno));
}
- sprintf(g_buffer, "%s/pwm%d/polarity",PWM_DEVICE_PATH, pin);
- g_pwm[pin].fd_polarity = open(g_buffer, O_WRONLY);
- if (g_pwm[pin].fd_polarity < 0)
+ sprintf(g_buffer, "%s/pwm%d/polarity", PWM_DEVICE_PATH, pin);
+ pwm->fd_polarity = open(g_buffer, O_WRONLY);
+ if (pwm->fd_polarity < 0)
{
- Abort("Couldn't open %s for PWM pin %d - %s", g_buffer, pin, strerror(errno));
+ close(pwm->fd_run);
+ AbortBool("Couldn't open %s for PWM%d - %s", g_buffer, pin, strerror(errno));
}
- sprintf(g_buffer, "%s/pwm%d/period_ns",PWM_DEVICE_PATH, pin);
- g_pwm[pin].file_period = fopen(g_buffer, "w");
- if (g_pwm[pin].file_period == NULL)
+ sprintf(g_buffer, "%s/pwm%d/period_ns", PWM_DEVICE_PATH, pin);
+ pwm->file_period = fopen(g_buffer, "w");
+ if (pwm->file_period == NULL)
{
- Abort("Couldn't open %s for PWM pin %d - %s", g_buffer, pin, strerror(errno));
+ close(pwm->fd_run);
+ close(pwm->fd_polarity);
+ AbortBool("Couldn't open %s for PWM%d - %s", g_buffer, pin, strerror(errno));
}
- sprintf(g_buffer, "%s/pwm%d/duty_ns",PWM_DEVICE_PATH, pin);
- g_pwm[pin].file_duty = fopen(g_buffer, "w");
- if (g_pwm[pin].file_duty == NULL)
+ sprintf(g_buffer, "%s/pwm%d/duty_ns", PWM_DEVICE_PATH, pin);
+ pwm->file_duty = fopen(g_buffer, "w");
+ if (pwm->file_duty == NULL)
{
- Abort("Couldn't open %s for PWM pin %d - %s", g_buffer, pin, strerror(errno));
+ close(pwm->fd_run);
+ close(pwm->fd_polarity);
+ fclose(pwm->file_period);
+ AbortBool("Couldn't open %s for PWM%d - %s", g_buffer, pin, strerror(errno));
}
// Don't buffer the streams
- setbuf(g_pwm[pin].file_period, NULL);
- setbuf(g_pwm[pin].file_duty, NULL);
+ setbuf(pwm->file_period, NULL);
+ setbuf(pwm->file_duty, NULL);
-
+ pwm->initialised = true;
+ Log(LOGDEBUG, "Exported PWM%d", pin);
+ return true;
}
+
/**
* Unexport a PWM pin and close its file descriptors
- * @param pin - The pin number
+ * @param pin - The sysfs pin number
*/
void PWM_Unexport(int pin)
{
- if (pin < 0 || pin > PWM_NUM_PINS)
+ if (pin < 0 || pin >= PWM_NUM_PINS)
{
- Abort("Invalid pin number %d", pin);
+ Abort("Invalid PWM pin number %d specified.", pin);
+ }
+
+ PWM_Pin *pwm = &g_pwm[pin];
+ if (!pwm->initialised)
+ {
+ Abort("PWM %d not initialised", pin);
}
// Close the file descriptors
- close(g_pwm[pin].fd_polarity);
- close(g_pwm[pin].fd_run);
- fclose(g_pwm[pin].file_period);
- fclose(g_pwm[pin].file_duty);
+ close(pwm->fd_polarity);
+ //Stop it, if it's still running
+ pwrite(pwm->fd_run, "0", 1, 0);
+ close(pwm->fd_run);
+ fclose(pwm->file_period);
+ fclose(pwm->file_duty);
+
+ pwm->initialised = false;
- //Unexport the pin
+ // Try unexport the pin, doesn't matter if it's already unexported.
sprintf(g_buffer, "%s/unexport", PWM_DEVICE_PATH);
- FILE * export = fopen(g_buffer, "w");
- if (export == NULL)
+ FILE * file_unexport = fopen(g_buffer, "w");
+ if (file_unexport == NULL)
{
- Abort("Couldn't open %s to unexport PWM pin %d - %s", g_buffer, pin, strerror(errno));
+ Abort("Couldn't open %s to unexport PWM pin %d - %s", g_buffer, pin, strerror(errno));
}
-
- fprintf(export, "%d", pin);
- fclose(export);
+ fprintf(file_unexport, "%d\n", pin);
+ fclose(file_unexport);
}
/**
- * Export ADC pins; http://beaglebone.cameon.net/home/reading-the-analog-inputs-adc
- * Can't use sysfs like GPIO or PWM pins
- * Bloody annoying how inconsistent stuff is on the Beaglebone
+ * Initialise ADC structures
+ * @param pin The ADC pin number
*/
-void ADC_Export()
+bool ADC_Export(int pin)
{
- for (int i = 0; i < ADC_NUM_PINS; ++i)
+ if (pin < 0 || pin >= ADC_NUM_PINS)
{
- sprintf(g_buffer, "%s/AIN%d", g_options.adc_device_path, i);
- g_adc[i].fd_value = open(g_buffer, O_RDONLY);
- if (g_adc[i].fd_value < 0)
- {
- Abort("Couldn't open ADC %d device file %s - %s", i, g_buffer, strerror(errno));
- }
-
- //setbuf(g_adc[i].file_value, NULL);
+ AbortBool("Invalid ADC pin %d specified.", pin);
+ }
+ else if (g_adc[pin].initialised)
+ {
+ Log(LOGNOTE, "ADC %d already initialised", pin);
+ return true;
+ }
+ sprintf(g_buffer, "%s/in_voltage%d_raw", ADC_DEVICE_PATH, pin);
+ g_adc[pin].fd_value = open(g_buffer, O_RDONLY);
+ if (g_adc[pin].fd_value <0)
+ {
+ AbortBool("Couldn't open ADC %d device file %s - %s", pin, g_buffer, strerror(errno));
}
+
+ g_adc[pin].initialised = true;
+ Log(LOGDEBUG, "Opened ADC %d", pin);
+ return true;
}
/**
* Unexport ADC pins
+ * @param pin The ADC pin number
*/
-void ADC_Unexport()
+void ADC_Unexport(int pin)
{
- for (int i = 0; i < ADC_NUM_PINS; ++i)
- close(g_adc[i].fd_value);
+ if (pin < 0 || pin >= ADC_NUM_PINS)
+ {
+ Abort("Invalid ADC pin %d specified.", pin);
+ }
+ else if (!g_adc[pin].initialised)
+ {
+ Abort("ADC %d already uninitialised", pin);
+ }
+
+ close(g_adc[pin].fd_value);
+ g_adc[pin].fd_value = -1;
+ g_adc[pin].initialised = false;
}
/**
* Set a GPIO pin
* @param pin - The pin to set. MUST have been exported before calling this function.
*/
-void GPIO_Set(int pin, bool value)
+bool GPIO_Set(int pin, bool value)
{
- if (pin < 0 || pin >= GPIO_INDEX_SIZE || g_gpio_index[pin] == 128)
+ if (pin < 0 || pin > GPIO_MAX_NUMBER || g_pin_gpio_to_index[pin] == 128)
{
- Abort("Not a useable pin (number %d)", pin);
+ AbortBool("Not a useable pin number: %d", pin);
}
- GPIO_Pin *gpio = &g_gpio[g_gpio_index[pin]];
+ GPIO_Pin *gpio = &g_gpio[g_pin_gpio_to_index[pin]];
+ if (!gpio->initialised)
+ {
+ AbortBool("GPIO %d is not initialised.", pin);
+ }
+ //Set the pin direction
if (pwrite(gpio->fd_direction, "out", 3, 0) != 3)
{
- Abort("Couldn't set GPIO %d direction - %s", pin, strerror(errno));
+ AbortBool("Couldn't set GPIO %d direction - %s", pin, strerror(errno));
}
- char c = '0' + (value);
+ char c = value ? '1' : '0';
if (pwrite(gpio->fd_value, &c, 1, 0) != 1)
{
- Abort("Couldn't read GPIO %d value - %s", pin, strerror(errno));
+ AbortBool("Couldn't read GPIO %d value - %s", pin, strerror(errno));
}
+ return true;
}
/**
* Read from a GPIO Pin
* @param pin - The pin to read
+ * @param result A pointer to store the result
+ * @return true on success, false otherwise
*/
-bool GPIO_Read(int pin)
+bool GPIO_Read(int pin, bool *result)
{
- if (pin < 0 || pin >= GPIO_INDEX_SIZE || g_gpio_index[pin] == 128)
+ if (pin < 0 || pin > GPIO_MAX_NUMBER || g_pin_gpio_to_index[pin] == 128)
{
- Log(LOGERR, "Not a useable pin (number %d)", pin);
- return false;
+ AbortBool("Not a useable pin number: %d", pin);
+ }
+
+ GPIO_Pin *gpio = &g_gpio[g_pin_gpio_to_index[pin]];
+ if (!gpio->initialised)
+ {
+ AbortBool("GPIO %d is not initialised.", pin);
}
- GPIO_Pin *gpio = &g_gpio[g_gpio_index[pin]];
if (pwrite(gpio->fd_direction, "in", 2, 0) != 2)
- Log(LOGERR,"Couldn't set GPIO %d direction - %s", pin, strerror(errno));
+ {
+ AbortBool("Couldn't set GPIO %d direction - %s", pin, strerror(errno));
+ }
+
char c = '0';
if (pread(gpio->fd_value, &c, 1, 0) != 1)
- Log(LOGERR,"Couldn't read GPIO %d value - %s", pin, strerror(errno));
-
- return (c == '1');
+ {
+ AbortBool("Couldn't read GPIO %d value - %s", pin, strerror(errno));
+ }
+ *result = (c == '1');
+ return true;
}
/**
* Activate a PWM pin
- * @param pin - The pin to activate
+ * @param pin - The sysfs pin number
* @param polarity - if true, pin is active high, else active low
* @param period - The period in ns
* @param duty - The time the pin is active in ns
*/
-void PWM_Set(int pin, bool polarity, long period, long duty)
+bool PWM_Set(int pin, bool polarity, long period, long duty)
{
Log(LOGDEBUG, "Pin %d, pol %d, period: %lu, duty: %lu", pin, polarity, period, duty);
- rewind(g_pwm[pin].file_duty);
+ if (pin < 0 || pin >= PWM_NUM_PINS)
+ {
+ AbortBool("Invalid PWM pin number %d specified.", pin);
+ }
- if (fprintf(g_pwm[pin].file_duty, "0") == 0)
+ PWM_Pin *pwm = &g_pwm[pin];
+ if (!pwm->initialised)
{
- Abort("Couldn't zero the duty cycle for PWM %d - s", pin, strerror(errno));
+ AbortBool("PWM %d is not initialised.", pin);
}
-
+
// Have to stop PWM before changing it
- if (pwrite(g_pwm[pin].fd_run, "0", 1, 0) != 1)
+ if (pwrite(pwm->fd_run, "0", 1, 0) != 1)
{
- Abort("Couldn't stop PWM %d - %s", pin, strerror(errno));
+ AbortBool("Couldn't stop PWM %d - %s", pin, strerror(errno));
}
- char c = '0' + polarity;
- if (pwrite(g_pwm[pin].fd_polarity, &c, 1, 0) != 1)
+ char c = polarity ? '1' : '0';
+ if (pwrite(pwm->fd_polarity, &c, 1, 0) != 1)
{
- Abort("Couldn't set PWM %d polarity - %s", pin, strerror(errno));
+ AbortBool("Couldn't set PWM %d polarity - %s", pin, strerror(errno));
}
-
- rewind(g_pwm[pin].file_period);
- rewind(g_pwm[pin].file_duty);
- if (fprintf(g_pwm[pin].file_period, "%lu", period) == 0)
+
+ //This must be done first, otherwise period/duty settings can conflict
+ if (fwrite("0", 1, 1, pwm->file_duty) < 1)
{
- Abort("Couldn't set period for PWM %d - %s", pin, strerror(errno));
+ AbortBool("Couldn't zero the duty for PWM %d - %s", pin, strerror(errno));
}
- if (fprintf(g_pwm[pin].file_duty, "%lu", duty) == 0)
+ if (fprintf(pwm->file_period, "%lu", period) < 0)
+ {
+ AbortBool("Couldn't set period for PWM %d - %s", pin, strerror(errno));
+ }
+
+
+ if (fprintf(pwm->file_duty, "%lu", duty) < 0)
{
- Abort("Couldn't set duty cycle for PWM %d - %s", pin, strerror(errno));
+ AbortBool("Couldn't set duty cycle for PWM %d - %s", pin, strerror(errno));
}
- if (pwrite(g_pwm[pin].fd_run, "1", 1, 0) != 1)
+
+ if (pwrite(pwm->fd_run, "1", 1, 0) != 1)
{
- Abort("Couldn't start PWM %d - %s", pin, strerror(errno));
+ AbortBool("Couldn't start PWM %d - %s", pin, strerror(errno));
}
+ return true;
}
/**
* Deactivate a PWM pin
- * @param pin - The pin to turn off
+ * @param pin - The syfs pin number
+ * @return true on success, false otherwise
*/
-void PWM_Stop(int pin)
+bool PWM_Stop(int pin)
{
+ if (pin < 0 || pin >= PWM_NUM_PINS)
+ {
+ AbortBool("Invalid PWM pin number %d specified.", pin);
+ }
+ else if (!g_pwm[pin].initialised)
+ {
+ AbortBool("PWM %d is not initialised.", pin);
+ }
+
if (pwrite(g_pwm[pin].fd_run, "0", 1, 0) != 1)
{
- Abort("Couldn't stop PWM %d - %s", pin, strerror(errno));
+ AbortBool("Couldn't stop PWM %d - %s", pin, strerror(errno));
}
+
+ return true;
}
/**
* Read an ADC value
* @param id - The ID of the ADC pin to read
- * @returns - The reading of the ADC channel
+ * @param value - A pointer to store the value read from the ADC
+ * @returns - The true if succeeded, false otherwise.
*/
-int ADC_Read(int id)
+bool ADC_Read(int id, int *value)
{
- char adc_str[ADC_DIGITS] = "";
- lseek(g_adc[id].fd_value, 0, SEEK_SET);
-
- int i = 0;
- for (i = 0; i < ADC_DIGITS-1; ++i)
+ char adc_str[ADC_DIGITS] = {0};
+
+ if (id < 0 || id >= ADC_NUM_PINS)
+ {
+ AbortBool("Invalid ADC pin %d specified.", id);
+ }
+ else if (!g_adc[id].initialised)
{
- if (read(g_adc[id].fd_value, adc_str+i, 1) != 1)
- break;
- if (adc_str[i] == '\n')
- {
- adc_str[i] = '\0';
- break;
- }
+ AbortBool("ADC %d is not initialised.", id);
}
- char * end;
- int val = strtol(adc_str, &end, 10);
- if (*end != '\0')
+ if (pread(g_adc[id].fd_value, adc_str, ADC_DIGITS-1, 0) == -1)
{
- Log(LOGERR, "Read non integer from ADC %d - %s", id, adc_str);
- }
- return val;
+ //AbortBool("ADC %d read failed: %s", id, strerror(errno));
+ return false;
+ }
+
+ *value = strtol(adc_str, NULL, 10);
+ return true;
}
+
+#ifndef _BBB
+//For running on systems that are not the BBB
+bool True_Stub(int arg, ...) { return true; }
+bool ADC_Read_Stub(int *val, ...) { *val = 0; return true; }
+bool GPIO_Read_Stub(bool *val, ...) { *val = false; return true; }
+#endif