MCU8MASS-1754 Move over to use _delay_ms in the library to prevent hang ups with the millis timer during low power

Author: M65649

src/http_client.cpp

@@ -8,6 +8,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <util/delay.h>
 
 // We only use profile 0 to keep things simple we also stick with spId 3
 // which we dedicate to HTTPS
@@ -123,7 +124,7 @@ static HttpResponse sendData(const char* endpoint,
 
         // Wait some before delivering the payload. The modem might hang if we
         // deliver it too quickly
-        delay(100);
+        _delay_ms(100);
 
         // Now we deliver the payload
         SequansController.writeBytes(data, data_length);

src/led_ctrl.cpp

@@ -1,6 +1,8 @@
 #include "led_ctrl.h"
 #include "log.h"
 
+#include <util/delay.h>
+
 #ifdef __AVR_AVR128DB48__ // MINI
 
 #define LED_CELL_PIN  PIN_PA0
@@ -95,21 +97,21 @@ void LedCtrlClass::toggle(Led led, bool is_from_system_event) {
 void LedCtrlClass::startupCycle() {
     for (int i = int(Led::CELL); i <= int(Led::USER); i++) {
         this->on(Led(i));
-        delay(50);
+        _delay_ms(50);
     }
 
     for (int i = int(Led::CELL); i <= int(Led::USER); i++) {
         this->off(Led(i));
-        delay(50);
+        _delay_ms(50);
     }
 
     for (int i = int(Led::USER); i >= int(Led::CELL); i--) {
         this->on(Led(i));
-        delay(50);
+        _delay_ms(50);
     }
 
     for (int i = int(Led::USER); i >= int(Led::CELL); i--) {
         this->off(Led(i));
-        delay(50);
+        _delay_ms(50);
     }
 }

src/low_power.cpp

@@ -4,11 +4,13 @@
 #include "log.h"
 #include "lte.h"
 #include "sequans_controller.h"
+#include "timeout_timer.h"
 
 #include <Arduino.h>
 #include <Wire.h>
 #include <avr/io.h>
 #include <avr/sleep.h>
+#include <util/delay.h>
 
 #define AT_COMMAND_DISABLE_EDRX                 "AT+SQNEDRX=0"
 #define AT_COMMAND_ENABLE_PSM                   "AT+CPSMS=1,,,\"%s\",\"%s\""
@@ -214,7 +216,7 @@ attemptToEnterPowerSaveModeForModem(const unsigned long waiting_time_ms) {
     SequansController.setPowerSaveMode(0, NULL);
 
     do {
-        delay(50);
+        _delay_ms(50);
         SequansController.clearReceiveBuffer();
     } while (SequansController.isRxReady());
 
@@ -223,11 +225,11 @@ attemptToEnterPowerSaveModeForModem(const unsigned long waiting_time_ms) {
     ring_line_activity = false;
 
     // Now we wait until the ring line to stabilize
+    const TimeoutTimer timeout_timer(waiting_time_ms);
     unsigned long last_time_active = millis();
-    const unsigned long start_time = millis();
 
     do {
-        delay(PSM_WAITING_TIME_DELTA_MS);
+        _delay_ms(PSM_WAITING_TIME_DELTA_MS);
 
         // Reset timer if there has been activity or the RING line is high
         if (ring_line_activity || RING_PORT.IN & RING_PIN_bm) {
@@ -239,7 +241,7 @@ attemptToEnterPowerSaveModeForModem(const unsigned long waiting_time_ms) {
             modem_is_in_power_save = true;
             return true;
         }
-    } while (millis() - start_time < waiting_time_ms);
+    } while (!timeout_timer.hasTimedOut());
 
     return false;
 }
@@ -314,6 +316,7 @@ static void enablePIT(void) {
     temp = CLKCTRL.XOSC32KCTRLA;
     temp &= ~CLKCTRL_ENABLE_bm;
     _PROTECTED_WRITE(CLKCTRL.XOSC32KCTRLA, temp);
+
     while (CLKCTRL.MCLKSTATUS & CLKCTRL_XOSC32KS_bm) {
         __asm__ __volatile__("nop\n\t");
     }
@@ -330,16 +333,21 @@ static void enablePIT(void) {
     temp |= CLKCTRL_ENABLE_bm;
     _PROTECTED_WRITE(CLKCTRL.XOSC32KCTRLA, temp);
 
+    RTC.CLKSEL |= RTC_CLKSEL_XOSC32K_gc;
+
     // Wait for registers to synchronize
     while (RTC.PITSTATUS) { __asm__ __volatile__("nop\n\t"); }
 
-    RTC.CLKSEL |= RTC_CLKSEL_XOSC32K_gc;
     RTC.PITINTCTRL |= RTC_PI_bm;
     RTC.PITCTRLA |= RTC_PERIOD_CYC32768_gc | RTC_PITEN_bm;
 
+    // Wait for registers to synchronize
+    while (RTC.PITSTATUS) { __asm__ __volatile__("nop\n\t"); }
+
     // The first PIT intterupt will not necessarily be at the period specified,
     // so we just wait until it has triggered and track the reminaing time from
     // there
+
     while (!pit_triggered) { __asm__ __volatile__("nop\n\t"); }
     pit_triggered = false;
 }
@@ -629,7 +637,7 @@ static void enableLDO(void) {
     digitalWrite(LOWQ_PIN, HIGH);
 
     // Wait a little to let LDO mode settle
-    delay(100);
+    _delay_ms(100);
 }
 
 /**
@@ -640,7 +648,7 @@ static void disableLDO(void) {
     digitalWrite(LOWQ_PIN, LOW);
 
     // Wait a little to let PWM mode settle
-    delay(100);
+    _delay_ms(100);
 }
 
 /**
@@ -785,8 +793,7 @@ void LowPowerClass::powerSave(void) {
 
         enableLDO();
 
-        // It's important that we stop the millis after enabling the LDO, as it
-        // uses delay() to wait for the LDO mode to settle
+        // Stop millis interrupt
         stop_millis();
 
         sleep_cpu();
@@ -816,8 +823,7 @@ void LowPowerClass::powerDown(const uint32_t power_down_time_seconds) {
     enablePIT();
     enableLDO();
 
-    // It's important that we stop the millis after enabling the LDO, as it uses
-    // delay() to wait for the LDO mode to settle
+    // Stop millis interrupt to prevent the timer waking up the core
     stop_millis();
 
     uint32_t remaining_time_seconds = power_down_time_seconds;

src/lte.cpp

@@ -4,8 +4,10 @@
 #include "log.h"
 #include "mqtt_client.h"
 #include "sequans_controller.h"
+#include "timeout_timer.h"
 
 #include <Arduino.h>
+#include <util/delay.h>
 
 #define AT_CONNECT                    "AT+CFUN=1"
 #define AT_DISCONNECT                 "AT+CFUN=0"
@@ -100,7 +102,7 @@ static void timezoneCallback(__attribute__((unused)) char* buffer) {
 
 bool LteClass::begin(const uint32_t timeout_ms, const bool print_messages) {
 
-    const uint32_t start = millis();
+    const TimeoutTimer timeout_timer(timeout_ms);
 
     // If low power is utilized, sequans controller will already been
     // initialized, so don't reset it by calling begin again
@@ -111,7 +113,7 @@ bool LteClass::begin(const uint32_t timeout_ms, const bool print_messages) {
     // Disconnect before configuration if already connected
     SequansController.writeCommand(AT_DISCONNECT);
 
-    delay(100);
+    _delay_ms(100);
     SequansController.clearReceiveBuffer();
 
     SequansController.registerCallback(TIMEZONE_CALLBACK, timezoneCallback);
@@ -162,17 +164,16 @@ bool LteClass::begin(const uint32_t timeout_ms, const bool print_messages) {
         Log.infof("Connecting to operator");
     }
 
-    while (!isConnected() && millis() - start < timeout_ms) {
+    while (!isConnected() && !timeout_timer.hasTimedOut()) {
         LedCtrl.toggle(Led::CELL, true);
-        delay(500);
+        _delay_ms(500);
 
         if (print_messages) {
             Log.rawf(".");
         }
     }
 
-    if (millis() - start >= timeout_ms) {
-
+    if (!isConnected()) {
         Log.rawf(" Was not able to connect to the network within the timeout "
                  "of %d ms. Consider increasing the timeout or checking your "
                  "cellular coverage.\r\n",
@@ -223,26 +224,32 @@ bool LteClass::begin(const uint32_t timeout_ms, const bool print_messages) {
 
         // Not valid time, have to do sync. First we wait some to see if we get
         // the timezone URC
-        const unsigned long start = millis();
-        while (millis() - start < TIMEZONE_WAIT_MS && !got_timezone) {}
+        const TimeoutTimer timezone_timer(TIMEZONE_WAIT_MS);
+
+        while (!timezone_timer.hasTimedOut() && !got_timezone) {}
 
         if (!got_timezone) {
-            // Do manual sync with NTP server
 
+            // Do manual sync with NTP server
             if (print_messages) {
                 Log.info("Did not get time from operator, doing NTP sync. "
                          "This can take some time...");
             }
 
             // Will break from this when we get the NTP sync
-            while (true) {
+
+            const TimeoutTimer ntp_sync_timer(timeout_ms);
+            bool got_ntp_sync = false;
+
+            while (!ntp_sync_timer.hasTimedOut() && !got_ntp_sync) {
 
                 // We might be disconnected from the network whilst doing the
                 // NTP sync, so return if that is the case
                 if (!isConnected()) {
-                    Lte.end();
                     Log.warn(
                         "Got disconnected from network whilst doing NTP sync");
+                    SequansController.unregisterCallback(TIMEZONE_CALLBACK);
+                    Lte.end();
                     return false;
                 }
 
@@ -262,9 +269,19 @@ bool LteClass::begin(const uint32_t timeout_ms, const bool print_messages) {
 
                 if (buffer[NTP_STATUS_INDEX] == NTP_OK) {
                     Log.info("Got NTP sync!");
+                    got_ntp_sync = true;
                     break;
                 }
             }
+
+            if (!got_ntp_sync) {
+                Log.warnf("Did not get NTP sync within timeout of %lu ms. "
+                          "Consider increasing timeout for Lte.begin()\r\n",
+                          timeout_ms);
+                SequansController.unregisterCallback(TIMEZONE_CALLBACK);
+                Lte.end();
+                return false;
+            }
         }
     }
 
@@ -285,8 +302,9 @@ void LteClass::end(void) {
 
         // Wait for the CEREG URC after disconnect so that the modem doesn't
         // have any pending URCs and won't prevent going to sleep
-        uint32_t start = millis();
-        while (isConnected() && millis() - start < 2000) {}
+        const TimeoutTimer timeout_timer(2000);
+        while (isConnected() && !timeout_timer.hasTimedOut()) {}
+
         SequansController.unregisterCallback(CEREG_CALLBACK);
 
         SequansController.clearReceiveBuffer();

src/mqtt_client.cpp

@@ -180,7 +180,6 @@ static void internalConnectedCallback(char* urc_data) {
         SequansController.writeBytes((uint8_t*)MQTT_DISCONNECT,
                                      strlen(MQTT_DISCONNECT),
                                      true);
-        delay(10);
         SequansController.clearReceiveBuffer();
 
         if (disconnected_callback != NULL) {
@@ -195,7 +194,6 @@ static void internalDisconnectCallback(char* urc_data) {
     SequansController.writeBytes((uint8_t*)MQTT_DISCONNECT,
                                  strlen(MQTT_DISCONNECT),
                                  true);
-    delay(10);
     SequansController.clearReceiveBuffer();
 
     if (disconnected_callback != NULL) {
@@ -402,8 +400,6 @@ bool MqttClientClass::begin(const char* client_id,
     SequansController.writeBytes((uint8_t*)MQTT_DISCONNECT,
                                  strlen(MQTT_DISCONNECT),
                                  true);
-
-    delay(100);
     SequansController.clearReceiveBuffer();
 
     // -- Configuration --
@@ -531,15 +527,20 @@ bool MqttClientClass::end(void) {
     SequansController.unregisterCallback(MQTT_ON_CONNECT_URC);
     SequansController.unregisterCallback(MQTT_ON_DISCONNECT_URC);
 
-    SequansController.writeBytes((uint8_t*)MQTT_DISCONNECT,
-                                 strlen(MQTT_DISCONNECT),
-                                 true);
-    delay(10);
-    SequansController.clearReceiveBuffer();
+    if (isConnected()) {
 
-    internalDisconnectCallback(NULL);
+        SequansController.writeBytes((uint8_t*)MQTT_DISCONNECT,
+                                     strlen(MQTT_DISCONNECT),
+                                     true);
 
-    connected_to_broker = false;
+        SequansController.clearReceiveBuffer();
+
+        connected_to_broker = false;
+    }
+
+    if (disconnected_callback != NULL) {
+        disconnected_callback();
+    }
 
     return true;
 }