AD8232: Adding C Source

Signed-off-by: Abhishek Malik <abhishek.malik@intel.com>

src/ad8232/ad8232.c

@@ -0,0 +1,87 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ *         Abhishek Malik <abhishek.malik@intel.com>
+ * Copyright (c) 2016 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "ad8232.h"
+
+ad8232_context ad8232_init(int lo_plus, int lo_minus, int output,
+                           float a_ref) {
+    ad8232_context dev =
+      (ad8232_context) malloc(sizeof(struct _ad8232_context));
+
+    if(dev == NULL){
+        printf("Unable to assign memory to the Heart Rate Monitor structure");
+        return NULL;
+    }
+
+    dev->gpio_lo_plus_pin = lo_plus;
+    dev->gpio_lo_minus_pin = lo_minus;
+    dev->aio_pin = output;
+
+    dev->aio = mraa_aio_init(dev->aio_pin);
+    dev->gpio_lo_plus = mraa_gpio_init(dev->gpio_lo_plus_pin);
+    dev->gpio_lo_minus = mraa_gpio_init(dev->gpio_lo_minus_pin);
+
+    if (dev->aio == NULL || dev->gpio_lo_minus == NULL ||
+        dev->gpio_lo_plus == NULL){
+        printf("The pins did not initialize correctly");
+        return NULL;
+    }
+
+    if (mraa_gpio_dir(dev->gpio_lo_minus, MRAA_GPIO_IN) != MRAA_SUCCESS ||
+        mraa_gpio_dir(dev->gpio_lo_plus, MRAA_GPIO_IN) != MRAA_SUCCESS){
+        printf("Couldn't set the direction for the GPIO pins");
+        return NULL;
+    }
+
+    dev->a_res = (1 << mraa_aio_get_bit(dev->aio));
+    return dev;
+}
+
+void ad8232_close(ad8232_context dev){
+    if (dev->gpio_lo_minus != NULL)
+        mraa_gpio_close(dev->gpio_lo_minus);
+    if (dev->gpio_lo_plus != NULL)
+        mraa_gpio_close(dev->gpio_lo_plus);
+    if (dev->aio != NULL)
+        mraa_aio_close(dev->aio);
+
+    free(dev);
+}
+
+upm_result_t ad8232_get_value(ad8232_context dev, int* value) {
+    int reading = 0;
+
+    if (mraa_gpio_read(dev->gpio_lo_minus) ||
+        mraa_gpio_read(dev->gpio_lo_plus)) {
+        reading = 0;
+    }
+    else {
+        reading = mraa_aio_read(dev->aio);
+    }
+
+    *value = reading;
+
+    return UPM_SUCCESS;
+}