diff --git a/libraries/Examples/examples/Example9_ResetsAndWatchdog/Example9_ResetsAndWatchdog.ino b/libraries/Examples/examples/Example9_ResetsAndWatchdog/Example9_ResetsAndWatchdog.ino new file mode 100644 index 00000000..81a1e0d5 --- /dev/null +++ b/libraries/Examples/examples/Example9_ResetsAndWatchdog/Example9_ResetsAndWatchdog.ino @@ -0,0 +1,196 @@ +/* Author: Stephen Fordyce (adapted from WDT example code by Adam Garbo - https://forum.sparkfun.com/viewtopic.php?f=169&t=52431&p=213296&hilit=watchdog#p213296) + Created: 24th July 2020 + License: MIT. See SparkFun Arduino Apollo3 Project for more information + + This example demonstrates use of the watchdog timer, also different ways of resetting the Artemis as well as how to determine the last reset type +*/ + +// Global variables +volatile uint8_t watchdogCounter = 0; // Watchdog interrupt counter +uint32_t resetStatus = 0; // Reset status register +bool testWatchdogResetFlag = false; +bool watchdogInterruptCallsEmergencyReset = false; +bool resetWDTEveryLoop = true; + +// Watchdog timer configuration structure. +am_hal_wdt_config_t g_sWatchdogConfig = { + //Substitude other values for AM_HAL_WDT_LFRC_CLK_16HZ to increase/decrease the range + .ui32Config = AM_HAL_WDT_LFRC_CLK_16HZ | AM_HAL_WDT_ENABLE_RESET | AM_HAL_WDT_ENABLE_INTERRUPT, // Configuration values for generated watchdog timer event. + //****** EVEN THOUGH THESE IMPLY 16-BIT, THEY ARE ONLY 8-BIT - 255 MAX! + .ui16InterruptCount = 120, //MAX 255! // Set WDT interrupt timeout for 5 seconds (120 / 16 = 8). // Number of watchdog timer ticks allowed before a watchdog interrupt event is generated. + .ui16ResetCount = 160 //MAX 255! // Set WDT reset timeout for 15 seconds (160 / 16 = 10). // Number of watchdog timer ticks allowed before the watchdog will issue a system reset. +}; + +void setup(void) +{ + pinMode(LED_BUILTIN, OUTPUT); + Serial.begin(115200); delay(10); + Serial.println();Serial.println(); + Serial.println("****Artemis Reset & Watchdog Reset Example****"); + + printResetReason(); //Explain reason for reset + am_hal_reset_control(AM_HAL_RESET_CONTROL_STATUSCLEAR, 0); // Clear reset status register for next time we reset. + delay(1000); + + startWatchdogTimer(); //Initialise and start the watchdog timer, in case the program gets stuck in a while loop or waiting for user input + printWatchdogDetails(); + delay(2000); + + Serial.println("\nRunning a time-consuming loop with watchdog running"); + for(int i=0; i<5; i++) + { + delay(1000); //Phew, a bunch of hard processing + printWatchdogValue(); + } + Serial.println("Yikes, the time kept increasing, even though we were doing legitimate work\n"); + + Serial.println("\nRunning a time-consuming loop that restarts the watchdog timer each loop"); + for(int i=0; i<5; i++) + { + delay(1000); //Phew, a bunch of hard processing + printWatchdogValue(); + am_hal_wdt_restart(); // "Pet" the dog. // Restart the watchdog. + } + Serial.println("Plenty of time, but the watchdog timer will still catch a freeze\n"); + delay(2000); +} + +void loop(void) +{ + Serial.println("Start of loop()"); + if(resetWDTEveryLoop) + am_hal_wdt_restart(); // "Pet" the dog. // Restart the watchdog. (every loop run seems good) + + if(resetWDTEveryLoop) + { + Serial.println("Enter 'r' to do a scheduled software reset"); + Serial.println("Enter 's' to stop resetting the watchdog timer each loop"); + delay(1000); + char option = Serial.read(); + if(option == 'r') + myScheduledReset(); + if(option == 's') + { + Serial.println("I take no responsibility for the consequences!"); + Serial.println("(the watchdog interrupt routine when triggered will reset the timer 3 times, watch the timer values to see when it's reset by the ISR)"); + delay(2000); + resetWDTEveryLoop = false; + } + } + + if(resetWDTEveryLoop == false) + { + Serial.println("Enter 'e' to let the watchdog interrupt call emergencyReset()"); + delay(1000); + char option = Serial.read(); + if(option == 'e') + { + Serial.println("Cool, that'll happen in a sec"); delay(20); + watchdogInterruptCallsEmergencyReset = true; + } + } + + if(testWatchdogResetFlag) + { + Serial.println("Just about to go down the rabbit hole..."); + delay(20); //Let serial buffer clear + while(1); //Intentionally get stuck, and hope that the watchdog timer saves the day + } + + printWatchdogValue(); + Serial.println(); + delay(10); + + //Optional code for sleeping - just halt the WDT before you disable everything, then re-initialise the WDT after waking up. Tested elsewhere, and does not have any appreciable impact on sleep currents or performance + //am_hal_wdt_halt(); + //sleepForABit(); + //startWatchdog(); +} + +// Interrupt handler for the watchdog. +extern "C" void am_watchdog_isr(void) +{ + am_hal_wdt_int_clear(); // Clear the watchdog interrupt. + if(watchdogInterruptCallsEmergencyReset) + emergencyReset(); + + if ( watchdogCounter < 3 ) // Catch the first three watchdog interrupts, but let the fourth through untouched. + { + digitalWrite(LED_BUILTIN, LOW); + am_hal_wdt_restart(); // "Pet" the dog (reset the timer) + } + else + { + digitalWrite(LED_BUILTIN, HIGH); // Indicator that a reset will occur. + testWatchdogResetFlag = true; + } + + watchdogCounter++; // Increment the number of watchdog interrupts. +} + +void startWatchdogTimer() +{ + am_hal_clkgen_control(AM_HAL_CLKGEN_CONTROL_LFRC_START, 0); // LFRC must be turned on for this example as the watchdog only runs off of the LFRC. + am_hal_wdt_init(&g_sWatchdogConfig); // Configure the watchdog. + NVIC_EnableIRQ(WDT_IRQn); // Enable the interrupt for the watchdog in the NVIC. + am_hal_interrupt_master_enable(); + am_hal_wdt_start(); // Enable the watchdog. +} + +//IMPORTANT: IF THIS IS CALLED BY THE WATCHDOG TIMER INTERRUPT ROUTINE, IT NEEDS TO BE QUICK (NO PRINTING TO SERIAL OR DELAYS) +void emergencyReset() +{ + //Optional: write some bits to flash/EEPROM to help with recovery + + am_hal_reset_control(AM_HAL_RESET_CONTROL_SWPOI,0); //Reset with option "Software Power On Initialization" SWPOI +// am_hal_reset_control(AM_HAL_RESET_CONTROL_SWPOR,0); //Reset with option SWPOR (same as SWPOI but different am_hal_reset_status bit) +} + +void myScheduledReset() +{ + //Optional: write some bits to flash/EEPROM to help with recovery + +// am_hal_reset_control(AM_HAL_RESET_CONTROL_SWPOI,0); //Reset with option "Software Power On Initialization" SWPOI + am_hal_reset_control(AM_HAL_RESET_CONTROL_SWPOR,0); //Reset with option SWPOR (same as SWPOI but different am_hal_reset_status bit) +} + +void printWatchdogDetails() +{ + Serial.print("Interrupt Count = "); Serial.print(g_sWatchdogConfig.ui16InterruptCount ); Serial.println(" ticks"); + Serial.print("Reset Count = "); Serial.print(g_sWatchdogConfig.ui16ResetCount); Serial.println(" ticks"); + + // Print out reset status register. + am_hal_reset_status_t sStatus; // (Note: See am_hal_reset.h for RESET status structure) + am_hal_reset_status_get(&sStatus); + resetStatus = sStatus.eStatus; + char rStatus[30]; + sprintf(rStatus, "Reset Status Register = 0x%x", resetStatus); // (Note: Watch Dog Timer reset = 0x40) + Serial.println(rStatus); +} + +void printWatchdogValue() +{ + Serial.print("Watchdog timer:"); + Serial.println(am_hal_wdt_counter_get()); +} + +void printResetReason() +{ + am_hal_reset_status_t resetResult; + uint32_t resultOk = am_hal_reset_status_get(&resetResult); + Serial.print("Reset reason: "); + if(resultOk == AM_HAL_STATUS_FAIL) Serial.println("Failed to get reset status"); + if(resetResult.bEXTStat) Serial.println("External reset"); + if(resetResult.bPORStat) Serial.println("Power-On reset"); + if(resetResult.bBODStat) Serial.println("Brown-Out reset"); + if(resetResult.bSWPORStat) Serial.println("SW Power-On reset or AIRCR reset - in this example, indicates reset by myScheduledReset()"); + if(resetResult.bSWPOIStat) Serial.println("SW Power On Initialization reset - in this example, indicates reset by emergencyReset()"); + if(resetResult.bDBGRStat) Serial.println("Debugger reset"); + if(resetResult.bWDTStat) Serial.println("Watch Dog Timer reset - nothing in the Watchdog Timer Interrupt routine got to restarting the Watchdog Timer"); + if(resetResult.bBOUnregStat) Serial.println("Unregulated Supply Brownout event"); + if(resetResult.bBOCOREStat) Serial.println("Core Regulator Brownout event"); + if(resetResult.bBOMEMStat) Serial.println("Memory Regulator Brownout event"); + if(resetResult.bBOBLEStat) Serial.println("BLE/Burst Regulator Brownout event"); +// am_hal_reset_control(AM_HAL_RESET_CONTROL_STATUSCLEAR, 0); // (do this in setup() Clear reset status register for next time we reset. + Serial.println(); +}