WIP: Add LED Alerts

app/CMakeLists.txt

@@ -7,7 +7,7 @@
 cmake_minimum_required(VERSION 3.20.0)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 
-project(app LANGUAGES C VERSION 0.1.0)
+project(app LANGUAGES C VERSION 0.2.1)
 
 configure_file(app_version.h.in ${CMAKE_BINARY_DIR}/app/include/app_version.h)
 target_include_directories(app PRIVATE ${CMAKE_BINARY_DIR}/app/include src)
@@ -22,6 +22,7 @@ set(PYRRHA_SOURCES
     src/bluetooth.c
     src/storage.c
     src/timestamp.c
+    src/alerts.c
 )
 target_include_directories(app PRIVATE include src)
 target_sources(app PRIVATE ${PYRRHA_SOURCES})

app/Kconfig

@@ -11,6 +11,10 @@ module = PYRRHA
 module-str = PYRRHA
 source "subsys/logging/Kconfig.template.log_config"
 
+module = ALERTS
+module-str = ALERTS
+source "subsys/logging/Kconfig.template.log_config"
+
 menu "pyrrha threads"
 menu "stacks"
 config PYRRHA_COLLECTION_STACKSIZE
@@ -56,6 +60,28 @@ config PYRRHA_FCB_MAGIC
 	  Magic 32-bit word for to identify valid settings area
 endmenu
 
+menu "alerts"
+
+config CO_ALERT_THRESHOLD_PPM
+    int "Threshold in ppm for co alerts"
+    range 1 1000
+    default 420
+	help
+	  Threshold in PPM for CO level when an alert is generated.
+	  420ppm is the AEGL2 10 minute limit.
+config NO2_ALERT_THRESHOLD_PPM
+    int "Threshold in ppm for no2 alerts"
+    range 1 100
+    default 8
+	help
+	  Threshold in PPM for NO2 level when an alert is generated.
+	  20ppm is the AEGL2 10 minute limit.
+config TEMPERATURE_ALERT_THRESHOLD_CELCIUS
+    int "Threshold in celcius for temperature alerts"
+    range 60 120
+    default 80
+endmenu
+
 config PYRRHA_SAMPLE_PERIOD
     int "Period (in seconds) of sensor data collection"
     range 1 300

app/boards/nrf52840dk_nrf52840.overlay

@@ -25,6 +25,16 @@
 	};
 };
 
+&pwm0 {
+	status = "okay";
+	ch0-pin = <13>;
+	ch0-inverted;
+	ch1-pin = <14>;
+	ch1-inverted;
+	ch2-pin = <15>;
+	ch2-inverted;
+};
+
 / {
 	gas_sensor: mics4514 {
 		label = "MICS4514";
@@ -35,4 +45,21 @@
 		rload-red-ohms = <47000>;
 		rload-ox-ohms = <22000>;
 	};
+	pwmleds {
+		compatible = "pwm-leds";
+		pwm_led0: pwm_led_0 {
+			pwms = <&pwm0 13>;
+		};
+		pwm_led1: pwm_led_1 {
+			pwms = <&pwm0 14>;
+		};
+		pwm_led2: pwm_led_2 {
+			pwms = <&pwm0 15>;
+		};
+	};
+	aliases {
+		red-pwm-led = &pwm_led0;
+		green-pwm-led = &pwm_led1;
+		blue-pwm-led = &pwm_led2;
+	};
 };

app/configs/debug.conf

@@ -19,6 +19,7 @@ CONFIG_UART_CONSOLE=y
 CONFIG_LOG=y
 CONFIG_LOG_MODE_IMMEDIATE=y
 CONFIG_PYRRHA_LOG_LEVEL_DBG=y
+CONFIG_ALERTS_LOG_LEVEL_DBG=y
 CONFIG_SENSOR_LOG_LEVEL_DBG=y
 CONFIG_I2C_LOG_LEVEL_DBG=y
 

app/include/alerts.h

@@ -0,0 +1,48 @@
+/**
+ * @file alerts.h
+ * @author Brian Bradley (brian.bradley.p@gmail.com)
+ * @date 2022-01-26
+ * 
+ * @copyright Copyright (C) 2022 LION
+ * 
+ * SPDX-License-Identifier: Apache-2.0
+ * 
+ */
+
+
+#ifndef __PYRRHA_BLUETOOTH_H
+#define __PYRRHA_BLUETOOTH_H
+
+#include <collector.h>
+
+/**
+ * @brief Check for and generate any alerts necessary based on
+ * sensor data
+ * 
+ * @param data : sensor data used to match alert conditions
+ * @retval 0 on success
+ * @retval -ENOLCK if alert mutex could not be locked within 250ms
+ * @retval -errno otherwise
+ */
+int generate_alerts(struct pyrrha_data * data);
+
+/**
+ * @brief Override the current alert condition.
+ * This will block local alert generation until a release is issued.
+ * 
+ * @param color : hex representation of led color used in alarm
+ * @retval 0 on success
+ * @retval -ENOLCK if alert mutex could not be locked within 250ms
+ */
+int override_alert(uint32_t color);
+
+/**
+ * @brief Release the current override for the LED. For instance, 
+ * if the host device disconnects and can no longer control the alarm
+ * 
+ * @retval 0 on success
+ * @retval -ENOLCK if alert mutex could not be locked within 250ms
+ */
+int release_alert_override();
+
+#endif

app/prj.conf

@@ -8,3 +8,4 @@ CONFIG_JSON_LIBRARY=y
 CONFIG_FLASH=y
 CONFIG_FLASH_MAP=y
 CONFIG_FCB=y
+CONFIG_PWM=y

app/src/alerts.c

@@ -0,0 +1,172 @@
+/**
+ * @file alerts.c
+ * @author Brian Bradley (brian.bradley.p@gmail.com)
+ * @brief 
+ * @date 2022-01-26
+ * 
+ * @copyright Copyright (C) 2022 LION
+ * 
+ * SPDX-License-Identifier: Apache-2.0
+ * 
+ */
+
+#include <alerts.h>
+#include <logging/log.h>
+#include <zephyr.h>
+#include <device.h>
+#include <drivers/pwm.h>
+
+LOG_MODULE_REGISTER(alerts, CONFIG_PYRRHA_LOG_LEVEL);
+
+#define OVER_TEMPERATURE(temp) (temp > CONFIG_TEMPERATURE_ALERT_THRESHOLD_CELCIUS)
+#define OVER_CO(co) (co > CONFIG_CO_ALERT_THRESHOLD_PPM)
+#define OVER_NO2(no2) (no2 > CONFIG_NO2_ALERT_THRESHOLD_PPM)
+
+/*
+ * 50hz is flicker fusion threshold. Modulated light will be perceived
+ * as steady by our eyes when blinking rate is at least 50.
+ */
+#define PERIOD_USEC	(USEC_PER_SEC / 50U)
+
+#define RED_LED_NODE DT_ALIAS(red_pwm_led)
+#define GREEN_LED_NODE DT_ALIAS(green_pwm_led)
+#define BLUE_LED_NODE DT_ALIAS(blue_pwm_led)
+
+#define COLOR_TO_PULSE(color, period)         (color == UINT8_MAX ? (period) : (color * (period) >> 8))
+
+/**
+ * @brief union which allows easy set/conversion to hex or rgb directly
+ * 
+ */
+typedef union Color{
+    uint32_t hex;
+    struct{
+        uint8_t red;
+        uint8_t green;
+        uint8_t blue;
+    };
+}color_t;
+
+/**
+ * @brief Configuration table for pwm led
+ * 
+ */
+struct pwm_cfg{
+    const struct device * pwm;
+    const uint8_t pin;
+    const uint8_t flags;
+    const uint32_t period;
+};
+
+/**
+ * @brief Container for all pwm leds associated with the rgb led
+ * 
+ */
+struct rgb_led_device{
+    const struct pwm_cfg red;
+    const struct pwm_cfg green;
+    const struct pwm_cfg blue;
+};
+
+K_MUTEX_DEFINE(mtx_alert);
+static color_t g_alert_override = {0};
+
+const struct rgb_led_device g_led = {
+    .red = {
+        .pwm = DEVICE_DT_GET(DT_PWMS_CTLR(RED_LED_NODE)),
+        .pin = DT_PWMS_CHANNEL(RED_LED_NODE),
+        .flags = DT_PWMS_FLAGS(RED_LED_NODE), 
+        .period = PERIOD_USEC
+    },
+    .green = {
+        .pwm = DEVICE_DT_GET(DT_PWMS_CTLR(GREEN_LED_NODE)),
+        .pin = DT_PWMS_CHANNEL(GREEN_LED_NODE),
+        .flags = DT_PWMS_FLAGS(GREEN_LED_NODE), 
+        .period = PERIOD_USEC
+    },
+    .blue = {
+        .pwm = DEVICE_DT_GET(DT_PWMS_CTLR(BLUE_LED_NODE)),
+        .pin = DT_PWMS_CHANNEL(BLUE_LED_NODE),
+        .flags = DT_PWMS_FLAGS(BLUE_LED_NODE), 
+        .period = PERIOD_USEC
+    },
+};
+
+/**
+ * @brief Set pwm output directly to the coresponding 8-bit color value
+ * 
+ * @param cfg : configuration table for pwm device
+ * @param color : 8-bit color value for the specified pwm
+ * @retval 0 on success
+ * @retval -ENODEV if no configuration table
+ * @retval -EFAULT if pwm set error
+ */
+static int set_pwm(const struct pwm_cfg * cfg, uint8_t color)
+{
+    if (cfg == NULL){
+        return -ENODEV;
+    }
+	const struct device *dev = cfg->pwm;
+    uint32_t pulse = COLOR_TO_PULSE(color, cfg->period);
+	/* Verify pwm_pin_set_usec() */
+	if (pwm_pin_set_usec(dev, cfg->pin, cfg->period, pulse, cfg->flags)) {
+		LOG_ERR("Fail to set the period and pulse width");
+		return -EFAULT;
+	}
+	return 0;
+}
+
+/**
+ * @brief Set the alert led to a specific color
+ * 
+ * @param color : rgb representation of desired color 
+ * @retval 0 on success
+ * @retval -errno otherwise
+ */
+static int set_alert_led(color_t color){
+    set_pwm(&g_led.red, color.red);
+    set_pwm(&g_led.green, color.green);
+    set_pwm(&g_led.blue, color.blue);
+    return 0;
+}
+
+/**
+ * @brief generate an alert from sensor data exceeding set thresholds
+ */
+static void threshold_alert(void){
+    const color_t alert_color = {
+        .red = 0xff
+    };
+    set_alert_led(alert_color);
+}
+
+int override_alert(uint32_t color){
+    if (k_mutex_lock(&mtx_alert, K_MSEC(250)) != 0){
+        return -ENOLCK;
+    }
+    g_alert_override.hex = color;
+    set_alert_led(g_alert_override);
+    k_mutex_unlock(&mtx_alert);
+    return 0;
+}
+
+int release_alert_override(){
+    return override_alert(0);
+}
+
+int generate_alerts(struct pyrrha_data * data){
+    if (k_mutex_lock(&mtx_alert, K_MSEC(250)) != 0){
+        return -ENOLCK;
+    }
+    /* Only generate an alert when there is no override condition */
+    if (g_alert_override.hex == 0){
+        if (OVER_TEMPERATURE(data->rht.temperature.val1) ||
+            OVER_CO(data->gas.co.val1) ||
+            OVER_NO2(data->gas.no2.val1))
+        {
+            threshold_alert();
+        }
+    }
+    k_mutex_unlock(&mtx_alert);
+    return 0;
+}

app/src/collector.c

@@ -14,6 +14,7 @@
 #include <collector.h>
 #include <messenger.h>
 #include <timestamp.h>
+#include <alerts.h>
 LOG_MODULE_REGISTER(collector, CONFIG_PYRRHA_LOG_LEVEL);
 
 void data_collection_process(void){
@@ -25,7 +26,12 @@ void data_collection_process(void){
         data.err |= (capture_rht_data(&data.rht) != 0 ? ERR_RHT_SENSOR : 0);
         data.timestamp = get_timestamp();
         capture_rht_data(&data.rht);
+
+        /* Queue data for storage and / or notification to a host */
         queue_sensor_data(&data);
+        /* Process any alerts based on current sample data */
+        generate_alerts(&data);
+
         k_sleep(K_SECONDS(CONFIG_PYRRHA_SAMPLE_PERIOD));
     }
 }