Actually char* / char[] (with or without const) are considered "normal" C strings.
String or std::string are non-trivial C++ types (aka class/object types).
String literals are also treated as const char[].
BTW
quite clearly const char* 
Hi ScruffR, Doesnt strcmp(const1, const2) check if const1 == const2? I did this and my led lights up in dark, but stays on in dim and bright when its supposed to turn off!
// Get data from subscribed topic ambience_C8, on / off led according to ambience status
void myAmbienceHandler(const char *event, const char *data){
if(strcmp(data, "Dark")){
digitalWrite(D2, HIGH);
Log.info("Led turns on");
}
else if(strcmp(data, "Bright")){
digitalWrite(D2, LOW);
Log.info("Led stays off");
}
else{
digitalWrite(D2, LOW);
Log.info("Led stays off");
}
}
Heres my full code, I changed most strings to char ( will do that for ledtoggle command) once i start debugging tomorrow.
Device 1 code
#include <blynk.h>
BlynkTimer timer;
SerialLogHandler logHandler(LOG_LEVEL_ERROR, {{"app", LOG_LEVEL_INFO}});
const int led3=D0; // Blynk Nightlight Control (Slider) + HTML Nightlight Toggle On/Off
int led3_status=-1; // HTML Nightlight Toggle On/Off
const int ldr=A0; // Blynk Ambience Brightness
int ldr_status=0; // Blynk Ambience Brightness
WidgetLCD lcd(V1); // Blynk LCD (Date Day Greeting + Ambience Status)
WidgetLCD lcd2(V3); // Blynk LCD (Temp + Pressure)
WidgetLCD lcd3(V5); // Blynk LCD (Door status)
const char auth[] = "";
bool ldrNeedUpdate = false;
void blynkLDRdata(){
ldrNeedUpdate = true;
}
// cannot be called from a Software Timer!
void mustDo() {
if (Particle.connected()) {
Blynk.run();
timer.run();
if (ldrNeedUpdate) {
ldr_status = analogRead(ldr);
Blynk.virtualWrite(V0, ldr_status);
ldrNeedUpdate = false;
}
}
Particle.process(); //Particle.process() is a blocking call, and blocks for a few milliseconds.
}
void softDelay(uint32_t timeout) {
for (uint32_t ms = millis(); millis() - ms < timeout; mustDo());
}
// Get Temperature data from subscribed topic and print on LCD
void myTempHandler(const char *event, const char *data){
char msg[128];
double val = atof(data);
Log.info("Temperature Handler executed, %f°C", val);
snprintf(msg, sizeof(msg), "%.2f°C %s", val, (val > 32.50) ? "Warm" : "Cool");
lcd2.print(0,0, msg);
}
void myPressHandler(const char *event, const char *data){
char msg[128];
double val = atof(data);
Log.info("Pressure Handler executed, %.2fPa", val);
snprintf(msg, sizeof(msg), "%.2fPa %s", val, (val > 900) ? "High" : "Low ");
lcd2.print(0,1, msg);
}
void myDoorHandler(const char *event, const char *data){
char msg[128];
Log.info("Door Handler executed: %s", data);
if(!strcmp(data, "DOOR UNLOCKED!")) {
snprintf(msg, sizeof(msg), "Your door was UNLOCKED on %s.\r\n"
"Please ignore if this was you."
, (const char*)Time.format("%a %e %b at %I:%M%p"));
Log.info(msg);
Blynk.email("email@.io", "SECURITY ALERT!", msg);
lcd3.print(0,0, "DOOR UNLOCKED!");
}
lcd3.print(0,0, "door locked ");
}
void setup(){
// Nightlight Toggle On/Off
pinMode(led3, OUTPUT);
Particle.function("led",ledToggle);
// HTML Ambience Brightness Gauge
ldr_status=analogRead(ldr); // pinMode not needed since analogRead used
Particle.variable("ldranalogvalue", ldr_status);
Blynk.begin(auth);
// bLYNK LCD Time Display (Set Timezone to SG using +8)
Time.zone(+8);
lcd.clear();
lcd2.clear();
lcd3.clear();
// IP ADDRESS
// iot_C8 MQTT sub to door status, temp and pressure data vals from D8 published temp and pressure readings
Particle.subscribe("D8_temperature", myTempHandler, MY_DEVICES);
Particle.subscribe("D8_pressure", myPressHandler, MY_DEVICES);
Particle.subscribe("D8_door_status", myDoorHandler, MY_DEVICES);
//Particle.subscribe("D8_", D8_Handlers, MY_DEVICES);
// Push ldrdata into blynk app every 3 seconds
timer.setInterval(2000, functions);
Log.info("Serial is Running");
}
void functions(){
// update ldr_value to gauge
blynkLDRdata();
pub_ambience_status();
}
void pub_ambience_status(){
char msg[10] = "";
if (ldr_status <= 100){
strncpy(msg, "Dark", sizeof(msg));
Particle.publish("ambience_C8", msg, PRIVATE);
lcd.print(9,0, "Dark ");
Log.info("Ambience Status - %s", msg);
}
else if (ldr_status >= 300){
strncpy(msg, "Bright", sizeof(msg));
Particle.publish("ambience_C8", msg, PRIVATE);
lcd.print(9,0, "Bright");
Log.info("Ambience Status - %s", msg);
}
else{
strncpy(msg, "Dim", sizeof(msg));
Particle.publish("ambience_C8", msg, PRIVATE);
lcd.print(9,0, "Dim ");
Log.info("Ambience Status - %s", msg);
}
}
void loop(){
mustDo();
DisplayTime();
DisplayDate();
softDelay(2000);
Greeting();
softDelay(2000);
}
void DisplayTime(){
lcd.print(0,0, (const char*)Time.format("%I:%M%p"));
}
void DisplayDate(){
lcd.print(0,1, (const char*)Time.format("%a %e %b "));
}
void Greeting(){
float hh = (Time.local() % 86400) / 3600.0; // Current decimal hour of the day , currenthr*24hr/1hr
if (hh < 5.0){
lcd.print(0, 1, "Midnight ");
}
else if (hh < 12.0){
lcd.print(0, 1, "Good Morning ");
}
else if (hh < 17.0){
lcd.print(0, 1, "Good Afternoon");
}
else if(hh < 20.0){
lcd.print(0, 1, "Good Evening ");
}
else if(hh < 24.0){
lcd.print(0, 1, "Night ");
}
}
int ledToggle(String command) {
if (command=="on") {
digitalWrite(led3,HIGH);
Log.info("HTML led3 on");
return 1;
}
else if (command=="off") {
digitalWrite(led3,LOW);
Log.info("HTML led3 off");
return 0;
}
else if (command=="read") {
return digitalRead(led3);
}
else {
return -1;
}
}
Device 2 code
#include <Adafruit_BMP280.h>
#include <blynk.h>
SerialLogHandler logHandler(LOG_LEVEL_ERROR, {{"app", LOG_LEVEL_INFO}});
Adafruit_BMP280 bmp; // I2C
BlynkTimer timer;
const int led1 = D2; // Ambience light
const int button = D4; // Fingerprint scanner
const char auth[] = "";
// HTML Temp + Press Gage Data
double t_temp;
double t_press;
// Update fingerprint status every 5s
Timer timer1(3000, fingerprint_scanner);
bool tempNeedUpdate = false;
bool pressNeedUpdate = false;
void tempdata(){
tempNeedUpdate = true;
}
void pressdata(){
pressNeedUpdate = true;
}
// cannot be called from a Software Timer!
void mustDo() {
if (Particle.connected()) {
Blynk.run();
timer.run();
if (tempNeedUpdate) {
char temp_data[16];
t_temp = bmp.readTemperature();
snprintf(temp_data, sizeof(temp_data), "%.2f", t_temp);
Particle.publish("D8_temperature", temp_data, PRIVATE);
tempNeedUpdate = false;
}
if (pressNeedUpdate) {
char press_data[16];
t_press = bmp.readPressure();
snprintf(press_data, sizeof(press_data), "%.2f", t_press);
Particle.publish("D8_pressure", press_data, PRIVATE);
pressNeedUpdate = false;
}
}
Particle.process();
}
void functions(){
tempdata();
pressdata();
}
void softDelay(uint32_t timeout) {
for (uint32_t ms = millis(); millis() - ms < timeout; mustDo());
}
// Get data from subscribed topic ambience_C8, on / off led according to ambience status
void myAmbienceHandler(const char *event, const char *data){
if(strcmp(data, "Dark")){
digitalWrite(D2, HIGH);
Log.info("Led turns on");
}
else if(strcmp(data, "Bright")){
digitalWrite(D2, LOW);
Log.info("Led stays off");
}
else /*if(strcmp(data, "Dim"))*/{
digitalWrite(D2, LOW);
Log.info("Led stays off");
}
}
inline void pubDoorState(bool state) {
int lastState = -1;
int curState = digitalRead(button);
if (curState != lastState) {
Particle.publish("D8_door_status", curState ? "door locked" : "DOOR UNLOCKED!");
lastState = curState;
}
}
void fingerprint_scanner() {
pubDoorState(digitalRead(button));
}
BLYNK_WRITE(V4) {
pubDoorState(param.asInt());
}
void setup() {
pinMode(led1, OUTPUT);
pinMode(button, INPUT_PULLUP);
// HTML Temp and pressure gauge reading
Particle.variable("temp", t_temp);
Particle.variable("press", t_press);
// iot_D8 Device MQTT subscribe to Ambience_C8
Particle.subscribe("ambience_C8", myAmbienceHandler, MY_DEVICES);
Blynk.begin(auth);
timer1.start();
// Update temp and press every 5 seconds
timer.setInterval(5000, functions);
Log.info("Serial is Running");
if (!bmp.begin()){
Log.warn("Can't find the sensor BMP280");
}
}
void loop(){
mustDo();
}
Not exactly. As the reference link above clarifies it compares them and returns the "difference" between the two.
Consequently equality would be indicated by 0, hence my code reads something like this
if(!LITERALCMP(data, "DOOR UNLOCKED!"))
notice the ! which means boolean negation (i.e. 0 -> true, non-zero -> false).
inline instructs the compiler to "copy" the respective function instead of using a jump instruction.
For very short functions like this one-liner inlining avoids the extra overhead for the jump and return instructions (including the intrinsic stack push/pop effort).
Hi ScruffR, I realised my temp publish data value is written into char, and published as const char,
char temp_data[16];
t_temp = bmp.readTemperature();
snprintf(temp_data, sizeof(temp_data), "%.2f", t_temp);
void myTempHandler(const char *event, const char *data){
Log.trace("%s: <%s>", event, data);
char msg[128];
double val = atof(data);
Log.info("Temperature Handler executed, %f°C", val);
snprintf(msg, sizeof(msg), "%.2f°C %s", val, (val > 32.50) ? "Warm" : "Cool");
lcd2.print(0,0, msg);
}
I might be able to answer that if you also provide the output of the Log.trace().
When questions like this arise that’s what the logs are for 
Here is the output
[68472] <[14|00|A8|00|07]vw[00]0[00]20
[68540] <[14|00|A9|00|12]vw[00]1[00]p[00]9[00]0[00]Dark [00]
0000068540 [app] INFO: Ambience Status - Dark
0000068545 [app] INFO: Temperature Handler executed, 31.22°C
[68607] <[14|00|AA|00|19]vw[00]3[00]p[00]0[00]0[00]31.22[C2|B0]C Cool[00]
[68759] <[14|00|AB|00|13]vw[00]1[00]p[00]0[00]0[00]02:19PM[00]
0000068803 [app] INFO: Pressure Handler executed, 100880.00Pa
[68826] <[14|00|AD|00|1C]vw[00]3[00]p[00]0[00]1[00]100880.00Pa High[00]
[68827] <[14|00|AC|00|1A]vw[00]1[00]p[00]0[00]1[00]Mon 25 Jan [00]
I have no idea why stack overflow still happens, I’ve tried using timers/the mustDo() function yet i cant fix it. I changed from strings to char, even double temp and press to char.
Device 1 Code
#define BLYNK_DEBUG
#define BLYNK_PRINT Serial
#include <blynk.h>
BlynkTimer timer;
SerialLogHandler logHandler(LOG_LEVEL_ERROR, {{"app", LOG_LEVEL_INFO}});
const int led3=D0; // Blynk Nightlight Control (Slider) + HTML Nightlight Toggle On/Off
int led3_status=-1; // HTML Nightlight Toggle On/Off
const int ldr=A0; // Blynk Ambience Brightness
int ldr_status=0; // Blynk Ambience Brightness
WidgetLCD lcd(V1); // Blynk LCD (Date Day Greeting + Ambience Status)
WidgetLCD lcd2(V3); // Blynk LCD (Temp + Pressure)
WidgetLCD lcd3(V5); // Blynk LCD (Door status)
const char auth[] = "";
bool ldrNeedUpdate = false;
void blynkLDRdata(){
ldrNeedUpdate = true;
}
bool ambienceNeedUpdate = false;
void UpdateAmbience(){
ambienceNeedUpdate = true;
}
// cannot be called from a Software Timer!
void mustDo() {
if (Particle.connected()) {
Blynk.run();
timer.run();
if (ldrNeedUpdate) {
ldr_status = analogRead(ldr);
Blynk.virtualWrite(V0, ldr_status);
ldrNeedUpdate = false;
}
if(ambienceNeedUpdate){
pub_ambience_status();
ambienceNeedUpdate = false;
}
}
Particle.process(); //Particle.process() is a blocking call, and blocks for a few milliseconds.
}
// Get Temperature data from subscribed topic and print on LCD
void myTempHandler(const char *event, const char *data){
Log.trace("%s: <%s>", event, data);
char msg[20];
double val = atof(data);
Log.info("Temperature Handler executed, %.2f°C", data);
snprintf(msg, sizeof(msg), "%.2f°C %s", val, (val > 32.50) ? "Warm" : "Cool");
lcd2.print(0,0, msg);
}
void myPressHandler(const char *event, const char *data){
//Log.trace("%s: <%s>", event, data);
char msg[20];
double val = atof(data);
Log.info("Pressure Handler executed, %.2fPa", val);
snprintf(msg, sizeof(msg), "%.2fPa %s", val, (val > 900) ? "High" : "Low ");
lcd2.print(0,1, msg);
}
void myDoorHandler(const char *event, const char *data){
//Log.trace("%s: <%s>", event, data);
char msg[60];
Log.info("Door Handler executed: %s", data);
if(!strcmp(data, "DOOR UNLOCKED!")) {
snprintf(msg, sizeof(msg), "Your door was UNLOCKED on %s.\r\n"
"Please ignore if this was you."
, (const char*)Time.format("%a %e %b at %I:%M%p"));
Log.info(msg);
Blynk.email("email@gmail.com", "SECURITY ALERT!", msg);
lcd3.print(0,0, "DOOR UNLOCKED!");
}
lcd3.print(0,0, "door locked ");
}
void softDelay(uint32_t timeout) {
for (uint32_t ms = millis(); millis() - ms < timeout; mustDo());
}
void setup(){
// Nightlight Toggle On/Off
pinMode(led3, OUTPUT);
Particle.function("led",ledToggle);
// HTML Ambience Brightness Gauge
ldr_status=analogRead(ldr); // pinMode not needed since analogRead used
Particle.variable("ldranalogvalue", ldr_status);
Blynk.begin(auth);
// bLYNK LCD Time Display (Set Timezone to SG using +8)
Time.zone(+8);
lcd.clear();
lcd2.clear();
lcd3.clear();
// IP ADDRESS
// iot_C8 MQTT sub to door status, temp and pressure data vals from D8 published temp and pressure readings
Particle.subscribe("D8_temperature", myTempHandler, MY_DEVICES);
Particle.subscribe("D8_pressure", myPressHandler, MY_DEVICES);
Particle.subscribe("D8_door_status", myDoorHandler, MY_DEVICES);
// Push ldrdata into blynk app every 3 seconds
//timer.setInterval(3000, blynkLDRdata);
timer.setInterval(3000, functions);
Log.info("Serial is Running");
}
void functions(){
blynkLDRdata();
UpdateAmbience();
}
void pub_ambience_status(){
char msg[10] = "";
if (ldr_status <= 100){
strncpy(msg, "Dark", sizeof(msg));
Particle.publish("C8_ambience", msg, PRIVATE);
lcd.print(9,0, "Dark ");
Log.info("Ambience Status - %s", msg);
}
else if (ldr_status >= 300){
strncpy(msg, "Bright", sizeof(msg));
Particle.publish("C8_ambience", msg, PRIVATE);
lcd.print(9,0, "Bright");
Log.info("Ambience Status - %s", msg);
}
else{
strncpy(msg, "Dim", sizeof(msg));
Particle.publish("C8_ambience", msg, PRIVATE);
lcd.print(9,0, "Dim ");
Log.info("Ambience Status - %s", msg);
}
}
void loop(){
mustDo();
DisplayTimeDate();
softDelay(2000);
Greeting();
softDelay(2000);
}
void DisplayTimeDate(){
lcd.print(0,0, (const char*)Time.format("%I:%M%p"));
lcd.print(0,1, (const char*)Time.format("%a %e %b "));
}
void Greeting(){
float hh = (Time.local() % 86400) / 3600.0; // Current decimal hour of the day , currenthr*24hr/1hr
if (hh < 5.0){
lcd.print(0, 1, "Midnight ");
}
else if (hh < 12.0){
lcd.print(0, 1, "Good Morning ");
}
else if (hh < 17.0){
lcd.print(0, 1, "Good Afternoon");
}
else if(hh < 20.0){
lcd.print(0, 1, "Good Evening ");
}
else if(hh < 24.0){
lcd.print(0, 1, "Night ");
}
}
int ledToggle(const char* command){ // Assign command str as const char
if(command="on") {
digitalWrite(led3,HIGH);
Log.info("HTML led3 on");
return 1;
}
else if(command="off") {
digitalWrite(led3,LOW);
Log.info("HTML led3 off");
return 0;
}
else if(command="read") {
Log.info("HTML led state");
return digitalRead(led3);
}
else {
return -1;
}
}
Device 2 Code
#define BLYNK_DEBUG
#define BLYNK_PRINT Serial
#define DEBUG_PRINT(...) { Particle.publish( "DEBUG", String::format(__VA_ARGS__) ); } void setup() { } void loop() { DEBUG_PRINT("HELLO"); delay(1000); }
#include <Adafruit_BMP280.h>
#include <blynk.h>
SerialLogHandler logHandler(LOG_LEVEL_ERROR, {{"app", LOG_LEVEL_INFO}});
Adafruit_BMP280 bmp; // I2C
BlynkTimer timer;
const int led1 = D2; // Ambience light
const int button = D4; // Fingerprint scanner
const char auth[] = "";
// HTML Temp + Press Gage Data
double t_temp;
double t_press;
void myAmbienceHandler(const char *event, const char *data);
// Update fingerprint status every 5s
Timer timer1(1000, fingerprint_scanner);
Timer timer2(5000, pub_Temp);
Timer timer3(20000, pub_Press);
bool tempNeedUpdate = false;
bool pressNeedUpdate = false;
void tempdata(){
tempNeedUpdate = true;
}
void pressdata(){
pressNeedUpdate = true;
}
void pub_Temp(){
char temp_data[16];
t_temp = bmp.readTemperature();
snprintf(temp_data, sizeof(temp_data), "%.2f", t_temp);
Particle.publish("D8_temperature", temp_data, PRIVATE);
}
void pub_Press(){
char press_data[16];
t_press = bmp.readPressure();
snprintf(press_data, sizeof(press_data), "%.2f", t_press);
Particle.publish("D8_pressure", press_data, PRIVATE);
}
// cannot be called from a Software Timer!
void mustDo() {
if (Particle.connected()) {
Blynk.run();
timer.run();
if (tempNeedUpdate) {
char temp_data[16];
t_temp = bmp.readTemperature();
snprintf(temp_data, sizeof(temp_data), "%.2f", t_temp);
Particle.publish("D8_temperature", temp_data, PRIVATE);
tempNeedUpdate = false;
}
if (pressNeedUpdate) {
char press_data[16];
t_press = bmp.readPressure();
snprintf(press_data, sizeof(press_data), "%.2f", t_press);
Particle.publish("D8_pressure", press_data, PRIVATE);
pressNeedUpdate = false;
}
}
Particle.process();
}
void functions(){
tempdata();
pressdata();
}
// Get data from subscribed topic ambience_C8, on / off led according to ambience status
void myAmbienceHandler(const char *event, const char *data){
//Log.trace("%s: <%s>", event, data);
if(!strcmp(data, "Dark")){
digitalWrite(D2, HIGH);
Log.info("Led turns on");
}
else if(!strcmp(data, "Bright") || !strcmp(data, "Dim")){
digitalWrite(D2, LOW);
Log.info("Led stays off");
}
}
void pubDoorState(bool state) { // bool state flag 1/0 button
Particle.publish("D8_door_status", state ? "door locked" : "DOOR UNLOCKED!");
}
void fingerprint_scanner() {
pubDoorState(digitalRead(button));
}
BLYNK_WRITE(V4) {
pubDoorState(param.asInt());
}
void softDelay(uint32_t timeout) {
for (uint32_t ms = millis(); millis() - ms < timeout; mustDo());
}
void setup() {
pinMode(led1, OUTPUT);
pinMode(button, INPUT_PULLUP);
// HTML Temp and pressure gauge reading
Particle.variable("temp", t_temp);
Particle.variable("press", t_press);
// iot_D8 Device MQTT subscribe to Ambience_C8
Particle.subscribe("ambience_C8", myAmbienceHandler, MY_DEVICES);
Blynk.begin(auth);
//timer1.start();
//timer2.start();
//timer3.start();
// Update temp and press every 5 seconds
timer.setInterval(5000, functions);
Log.info("Serial is Running");
if (!bmp.begin()){
Log.warn("Can't find the sensor BMP280");
}
}
void loop(){
mustDo();
//Blynk.run();
fingerprint_scanner();
softDelay(1000);
}
You won't see the Log.trace() output of your subscription handler because you didn't do that
To make it absolutely clear what that meant, you need this
SerialLogHandler logHandler(LOG_LEVEL_ERROR, {{ "app", LOG_LEVEL_ALL }});
I won't address this any further since I already provided some code that - by your own admission - does not suffer from that.
You also haven't pull through with this
This should have helped to locate the code section where the crash comes from. Without that info it would be chasing the wind to guess where it comes from.
Thanks ScruffR! I can see the trace info now!
0000020638 [app] INFO: Door Handler executed: door locked
0000020940 [app] TRACE: D8_temperature: <31.25>
void myTempHandler(const char *event, const char *data){
Log.trace("%s: <%s>", event, data);
char msg[20];
double val = atof(data);
Log.info("Temperature Handler executed, %.2f°C", data);
snprintf(msg, sizeof(msg), "%.2f°C %s", val, (val > 32.50) ? "Warm" : "Cool");
lcd2.print(0,0, msg);
}
When i run the code, I this output, does this mean that the line 136 where the if statement lies, is the issue that causes stack overflow? It’s been two weeks straight working on my first photon particle project with very basic c++ that i picked up in class. I will be back in 10hours to try debug again… “sigh”
0000192231 [app] TRACE: D8_door_status: <door locked>
0000192231 [app] INFO: Door Handler executed: door locked
0000193452 [app] TRACE: D8_door_status: <door locked>
0000193452 [app] INFO: Door Handler executed: door locked
0000194245 [app] TRACE: D8_door_status: <door locked>
0000194245 [app] INFO: Door Handler executed: door locked
**0000/194769 [app] INFO: Ambience Status - Dark**
** 136**
**0000195250 [app] TRACE: D8_door_status: <door locked>**
0000195250 [app] INFO: Door Handler executed: door locked
0000196255 [app] TRACE: D8_door_status: <door locked>
0000196255 [app] INFO: Door Handler executed: door locked
0000197263 [app] TRACE: D8_door_status: <door locked>
0000197264 [app] INFO: Door Handler executed: door locked
0000197767 [app] INFO: Ambience Status - Dark
136
0000198454 [app] TRACE: D8_door_status: <door locked>
0000198454 [app] INFO: Door Handler executed: door locked
133void pub_ambience_status(){
134 char msg[10] = "";
135
**136 if (ldr_status <= 100){**
137 strncpy(msg, "Dark", sizeof(msg));
138 Particle.publish("C8_ambience", msg, PRIVATE);
139 lcd.print(9,0, "Dark ");
140 Log.info("Ambience Status - %s", msg);
141 Serial.printlnf("%4d", __LINE__); delay(10);
142
143 }
else if (ldr_status >= 300){
strncpy(msg, "Bright", sizeof(msg));
Particle.publish("C8_ambience", msg, PRIVATE);
lcd.print(9,0, "Bright");
Log.info("Ambience Status - %s", msg);
Serial.printlnf("%4d", __LINE__); delay(10);
}
else{
strncpy(msg, "Dim", sizeof(msg));
Particle.publish("C8_ambience", msg, PRIVATE);
lcd.print(9,0, "Dim ");
Log.info("Ambience Status - %s", msg);
Serial.printlnf("%4d", __LINE__); delay(10);
}
}
Not a surprise there since you cannot compare string data to a number literal in a meaningful way like that.
Why on earth would you do that? Numeric values are best compared as numbers not as text.
No.
As I said earlier
Adding only one of these "beacon" lines will not help much. You need to add multiple such lines wherever you imagine the crash may happen and then wait for the crash to hit. The last line printed before the crash was obviously still executed but the next was not reached so the problem must lay between.
The narrower the gap between two of these lines the more precise your error detection will be.
BTW, I also told you about the need for a reference line due to the offset between the logged line number and the line number in your editor.
Hi ScruffR! Here is my output, I’ve added crash detection to every function
example
void function(){
Serial.printlnf("%4d func start", __LINE__); delay(10);
Serial.printlnf("%4d func end", __LINE__); delay(10);
}
106 reference <-- LINE, setup start
...
...
...
32 Must Do func start
51 Must Do func end
32 Must Do func start
51 Must Do func end
32 Must Do func start
83 Door Handler func start
0000054253 [app] TRACE: D8_door_status: <door locked>
0000054253 [app] INFO: Door Handler executed: door locked
83 Door Handler func start
0000054264 [app] TRACE: D8_door_status: <DOOR UNLOCKED!>
0000054264 [app] INFO: Door Handler executed: DOOR UNLOCKED!
0000054265 [app] INFO: Your door was UNLOCKED on Tue 26 Jan at 10:05AM.
Please ig
83 Door Handler func start
this is my analysis with auto crash detection on start and end of function
can i say that the issue with code is along my 3 handlers because they start but do not close? I’m kind of lost, I think it would be easier for me to understand if there was an example!
Update (Further testing):
pub ambience + press,temp,door
test1 - 4min runtime, stack overflow
test2 - ??
test3 - ??
pub ambience + sub press, temp = ??runtime, no overflow
pub ambience + sub press, door = ??runtime, no overflow
pub ambience + sub press = ??runtime, no overflow
pub ambience + sub temp = ??runtime, no overflow
pub ambience + sub door = ??runtime, no overflow
sub press, temp(5mins, status=online, no overflow)
sub press, door
sub press,temp,door (test1,2,3 lasted 2mins, status=offline)
51 Must Do func end
32 Must Do func start
150 function start
153 function end
158 Pub Status func start
0000276027 [app] INFO: Ambience Status - Dark
182 Pub Status func end
51 Must Do func end
195 Void loop end
186 Void loop start
32 Must Do func start
51 Must Do func end
...
...
...
153 function end
158 Pub Status func start
0000279020 [app] INFO: Ambience Status - Dark
182 Pub Status func end
51 Must Do func end
...
...
...
51 Must Do func end
209 Greeting func start
226 Greeting func end
32 Must Do func start
51 Must Do func end
...
...
...
51 Must Do func end
32 Must Do func start
83 Door Handler func start
0000283475 [app] TRACE: D8_door_status: <door locked>
0000283475 [app] INFO: Door Handler executed: door locked
97 Door Handler func end
51 Must Do func end
32 Must Do func start
51 Must Do func end
...
...
...
32 Must Do func start
51 Must Do func end
32 Must Do func start
51 Must Do func end
32 Must Do func start
57 Temp Handler func start
0000284811 [app] TRACE: D8_temperature: <30.36>
0000284811 [app] INFO: Temperature Handler executed, 30.36°C
70 Press Handler func start
0000284822 [app] TRACE: D8_pressure: <101118.45>
0000284822 [app] INFO: Pressure Handler executed, 101118.45Pa
83 Door Handler func start
I said
That means you take 106 which the reference line prints and the look in your editor at which line number you find that reference line and then calculate the difference between these two numbers (printed_line_number minus editor_line_number = offset, should be positive).
Once you have the offset you subtract that from your printe_crash_line_number (e.g. 83) to know at which line number you need to look in your editor.
To make things a bit neater it would be advisable to have setup() and loop() be the first functions and all your own functions follow these. That way you'd also be sure, that the offset will be calculated correctly for the entire project.
Particularly mashing setup() and loop() between your own functions and then also have other functions between setup() and loop() is not only poor but bad coding style.
BTW, you can make things easier for you.
Instead of writhing a special text for each function like
void someFn() {
Serial.println("%4d someFn start", __LINE__);
...
Serial.println("%4d someFn end", __LINE__);
}
just write
void someFn() {
Serial.println(">(%4d) %s", __LINE__, __FUNCTION__);
...
Serial.println("<(%4d) %s", __LINE__, __FUNCTION__);
}
If you have multiple return statements, you need a "<" line infront of all of them.
Hi ScruffR! I think I understand now! So my code editor line 26 is where i put the Serial.print(), while the reference line number printed was 26. So the difference between this offset is.. 0?
Code editor
25 void setup(){
26 Serial.printlnf("%4d <-- reference line", __LINE__);
27 pinMode(led3, OUTPUT);
26 <-- reference line
47 setup end
52 void loop start
178 display start
181 display end
...
...
201 greet end
124 temp hand start
134 press hand start
144 door hand start
This assertion seems reasonable.
If you want to drill down further you can add some more print lines between all the code lines in that region.
Working on it right now!
I forgot to include an “else” after the “if” statement! I just tested it and my code works!! its been running for 10minutes and it has just crashed again! Now the crash goes here, reading code again to check for errors right now…
162 door hand else start
124 temp hand start
134 press hand start
BEFORE
lcd3.print(0,0, "DOOR UNLOCKED!");
}
lcd3.print(0,0, "door locked ");
}
AFTER
}
else{
Serial.printlnf("%4d door hand else start", __LINE__); delay(10);
lcd3.print(0,0, "door locked ");
Serial.printlnf("%4d door hand else end LOCEKD", __LINE__); delay(10);
}
Serial.printlnf("%4d door hand after if else{} <here>", __LINE__); delay(10);
Serial.printlnf("%4d door hand end", __LINE__); delay(10);
}
134 press hand start
144 door hand start
159 door hand after if{} <here>
When you have the line numbers you don’t need to modify the text of the message for each line. That makes debugging unnecessarily cumbersome.
Hmm… seems like I should have used float val = atof(data) instead of double val = atof(data). It takes around 10minutes for stack overflow to occur!
Hi ScruffR! Okay thanks I’ll keep that in mind! Quick question, if i having float val = atof(data) = 32.00000
and comparing like this (val > 32.50) gives error, Do i use (val > 32.5 instead)
void softDelay(uint32_t timeout) {
for (uint32_t ms = millis(); millis() - ms < timeout; DoLoop());
}
I’ll be back tomorrow to debug again!