tests: add test for lis2dh12 device driver

tests/driver_lis2dh12/Makefile

@@ -0,0 +1,10 @@
+include ../Makefile.tests_common
+
+# as default we use the SPI mode for now, as the I2C mode is not supported, yet
+DRIVER ?= lis2dh12_spi
+
+USEMODULE += fmt
+USEMODULE += xtimer
+USEMODULE += $(DRIVER)
+
+include $(RIOTBASE)/Makefile.include

tests/driver_lis2dh12/README.md

@@ -0,0 +1,11 @@
+# About
+This is a manual test application for the LIS2DH12 accelerometer driver.
+
+# Usage
+This test application will initialize the accelerometer with its default
+parameters (as defined in `drivers/lis2dh12/include/lis2dh12_params.h`:
+ - `LIS2DH12_PARAM_SCALE`:  100Hz
+ - `LIS2DH12_PARAM_RATE`:   2G
+
+After initialization, the sensor reads the acceleration values every 100ms
+and prints them to the STDOUT.

tests/driver_lis2dh12/main.c

@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) 2018 Freie Universität Berlin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     tests
+ * @{
+ *
+ * @file
+ * @brief       Test application for the LIS2DH12 accelerometer driver
+ *
+ * @author      Hauke Petersen <hauke.petersen@fu-berlin.de>
+ *
+ * @}
+ */
+
+#include <stdio.h>
+
+#include "fmt.h"
+#include "xtimer.h"
+#include "lis2dh12.h"
+#include "lis2dh12_params.h"
+
+
+#define DELAY       (100UL * US_PER_MS)
+
+/* allocate some memory to hold one formated string for each sensor output, so
+ * one string for the X, Y, and Z reading, respectively */
+static char str_out[3][8];
+
+/* allocate device descriptor */
+static lis2dh12_t dev;
+
+int main(void)
+{
+    puts("LIS2DH12 accelerometer driver test application\n");
+
+    puts("Initializing LIS2DH12 sensor... ");
+    if (lis2dh12_init(&dev, &lis2dh12_params[0]) == LIS2DH12_OK) {
+        puts("[OK]");
+    }
+    else {
+        puts("[Failed]\n");
+        return 1;
+    }
+
+    xtimer_ticks32_t last_wakeup = xtimer_now();
+    while (1) {
+        /* read sensor data */
+        int16_t data[3];
+        if (lis2dh12_read(&dev, data) != LIS2DH12_OK) {
+            puts("error: unable to retrieve data from sensor, quitting now");
+            return 1;
+        }
+
+        /* format data */
+        for (int i = 0; i < 3; i++) {
+            size_t len = fmt_s16_dfp(str_out[i], data[i], 3);
+            str_out[i][len] = '\0';
+        }
+
+        /* print data to STDIO */
+        printf("X: %8s Y: %8s Z: %8s\n", str_out[0], str_out[1], str_out[2]);
+
+        xtimer_periodic_wakeup(&last_wakeup, DELAY);
+    }
+
+    return 0;
+}