examples/scd41: Add new example for scd41 CO2 sensor

Add new example for scd41 CO2 sensor application.

examples/scd41/Kconfig

@@ -0,0 +1,36 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+config EXAMPLES_SCD41
+	tristate "SCD41 CO2 sensor example"
+	default n
+	depends on SENSORS_SCD41
+	---help---
+		Enable the SCD41 CO2 sensor example
+
+if EXAMPLES_SCD41
+
+config EXAMPLES_SCD41_PROGNAME
+	string "Program name"
+	default "scd41"
+	---help---
+		This is the name of the program that will be used when the NSH ELF
+		program is installed.
+
+config EXAMPLES_SCD41_DEVPATH
+	string "Device path"
+	default "/dev/co2"
+	---help---
+		The device path
+
+config EXAMPLES_SCD41_PRIORITY
+	int "scd41 task priority"
+	default 100
+
+config EXAMPLES_SCD41_STACKSIZE
+	int "scd41 stack size"
+	default DEFAULT_TASK_STACKSIZE
+
+endif

examples/scd41/Make.defs

@@ -0,0 +1,23 @@
+############################################################################
+# apps/examples/scd41/Make.defs
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+ifneq ($(CONFIG_EXAMPLES_SCD41),)
+CONFIGURED_APPS += $(APPDIR)/examples/scd41
+endif

examples/scd41/Makefile

@@ -0,0 +1,34 @@
+############################################################################
+# apps/examples/scd41/Makefile
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements.  See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.  The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+include $(APPDIR)/Make.defs
+
+# scd41 co2 sensor built-in application info
+
+PROGNAME  = $(CONFIG_EXAMPLES_SCD41_PROGNAME)
+PRIORITY  = $(CONFIG_EXAMPLES_SCD41_PRIORITY)
+STACKSIZE = $(CONFIG_EXAMPLES_SCD41_STACKSIZE)
+MODULE    = $(CONFIG_EXAMPLES_SCD41)
+
+# scd41 co2 sensor Example
+
+MAINSRC = scd41_main.c
+
+include $(APPDIR)/Application.mk

examples/scd41/scd41_main.c

@@ -0,0 +1,87 @@
+/****************************************************************************
+ * apps/examples/scd41/scd41_main.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <nuttx/sensors/scd41.h>
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * scd41_main
+ ****************************************************************************/
+
+int main(int argc, FAR char *argv[])
+{
+  struct scd41_conv_data_s data;
+  int fd;
+  int ret;
+  int i;
+
+  printf("scd41 app is running.\n");
+
+  fd = open(CONFIG_EXAMPLES_SCD41_DEVPATH, O_RDWR);
+  if (fd < 0)
+    {
+      printf("ERROR: open failed: %d\n", fd);
+      return -1;
+    }
+
+  for (i = 0; i < 20; i++)
+    {
+      /* Sensor data is updated every 5 seconds. */
+
+      sleep(5);
+
+      ret = ioctl(fd, SNIOC_READ_CONVERT_DATA, (unsigned long)&data);
+      if (ret < 0)
+        {
+          printf("Read error.\n");
+          printf("Sensor reported error %d\n", ret);
+        }
+      else
+        {
+          printf("CO2[ppm]: %.2f, Temperature[C]: %.2f, RH[%%]: %.2f\n",
+                 data.co2, data.temperature, data.humidity);
+        }
+    }
+
+  ret = ioctl(fd, SNIOC_STOP, 0);
+  if (ret < 0)
+    {
+      printf("Failed to stop: %d\n", errno);
+    }
+
+  close(fd);
+
+  return 0;
+}