system
November 11, 2013, 8:46am
1
Hi all
I'm working on a LED altimeter to be used on a multirotor; Everything works perfectly, but I have a problem with the standard Hitachi 2x16 display used the project: after a few seconds from start it shows messy characters . Here you can find some more informations:
In the setup part of the sketch i "prepare" the display; in the loop section i continuosly update text showing content of some variables
I have power leds driven by a 540 MOSFET, never hot never even warm
The program starts normally, led blinks, variables are shown, but after 15-20 seconds strange characters start to be shown, and soon all the display becomes a mess
If i put the "digitalWrite(PinLed, Led)" command in the program leds blinks and problem happen; if I change the line as a comment with // no problems at all, even for half an hour
Arduino ONE is powered by an USB3.0 port of my pc; Leds have a 12v dedicated battery
If I keep the "digitalWrite(PinLed, Led)" command in the sketch, but i disconnect the 12v Led battery the problem persist
At the beginning I had display and other components on the same breadboard and the problem started after 3-4 seconds; now i moved the display on another separate board and the problem takes around 12-15 seconds to start
Some images:
The messy display
The good one (first 12-15 running seconds)
Two breadboards (and messy display)
Does anyone have some ideas to deal with? Thank you very much and ciao.
system
November 11, 2013, 1:39pm
3
Here it is:
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
String Ver = "0.239";
int TotalFlash = 0;
int CtrFlash = 1;
long FlashON = 0;
long FlashOFF = 0;
long Pause = 1500;
int Led = LOW;
long TimeTarget = 0;
long CurrentTime = 0;
int ButtonDelay = 500;
int Altitude=0;
int PrevAltitude=0;
int AltitudeRangeInf=0;
int AltitudeRangeSup=0;
int StartAltitude=0;
int SensorValue=0;
int SampleInterval=2500;
long NextSample=0;
int PercError=5;
int InFlightFlag = 0;
String Status = "PF"; // Status PF=preflight, UP=ascending, DN=descending, LV=leveled, TG=alti target, LN=Landing, LD=Landed, OF=Off
int TargetAlti = 50;
int VariAlti = 10;
int PinLed = 6;
int PinPiu = 8;
int PinMeno = 7;
int PressPiu = 0;
int PressMeno = 0;
void setup() {
TimeTarget = Pause;
pinMode(PinLed, OUTPUT);
pinMode(PinPiu, INPUT);
pinMode(PinMeno, INPUT);
lcd.begin(16, 2);
lcd.print("AltiLight v"+Ver);
delay(2500);
lcd.clear();
SensorValue = analogRead(A0);
Altitude=150-SensorValue/10;
lcd.setCursor(0, 0);
lcd.print("Altitude init");
lcd.setCursor(0, 1);
lcd.print("Quota OSL:");
lcd.setCursor(10, 1);
lcd.print(Altitude);
delay(2500);
PrevAltitude = 0;
StartAltitude=Altitude;
NextSample=SampleInterval;
Altitude=0;
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("St: Alti:");
lcd.setCursor(0, 1);
lcd.print("Trg: S:");
lcd.setCursor(3, 0);
lcd.print(Status);
lcd.setCursor(11, 0);
lcd.print(Altitude);
lcd.setCursor(4, 1);
lcd.print(TargetAlti);
Serial.begin(9600);
}
void loop() {
PressPiu=digitalRead(PinPiu);
PressMeno=digitalRead(PinMeno);
if(PressPiu == HIGH) {
TargetAlti = TargetAlti + VariAlti;
if (TargetAlti>250) {
TargetAlti = 250;
}
lcd.setCursor(4, 1);
lcd.print(TargetAlti);
delay(ButtonDelay);
}
if(PressMeno == HIGH) {
TargetAlti = TargetAlti - VariAlti;
if (TargetAlti<0) {
TargetAlti = 0;
}
lcd.setCursor(4, 1);
lcd.print(TargetAlti);
if(TargetAlti == 90) {
lcd.setCursor(6, 1);
lcd.print(" ");
}
delay(ButtonDelay);
}
if(Status=="PF") {
TotalFlash = 1;
FlashON = 100;
FlashOFF = 100;
}
if(Status=="UP") {
TotalFlash = 3;
FlashON = 100;
FlashOFF = 250;
}
if(Status=="DN") {
TotalFlash = 5;
FlashON = 100;
FlashOFF = 250;
}
if(Status=="LV") {
TotalFlash = 5;
FlashON = 500;
FlashOFF = 500;
}
if(Status=="TG") {
TotalFlash = 15;
FlashON = 50;
FlashOFF = 100;
}
if(Status=="LN") {
TotalFlash = 3;
FlashON = 1500;
FlashOFF = 200;
}
if(Status=="LD") {
TotalFlash = 50;
FlashON = 25;
FlashOFF = 50;
}
if(Status=="OF") {
TotalFlash = 0;
FlashON = 25;
FlashOFF = 50;
}
unsigned long CurrentTime = millis();
if (CurrentTime>=TimeTarget) {
if (Led == LOW) {
Led = HIGH;
TimeTarget=TimeTarget+FlashON;
CtrFlash++;
}
else {
Led = LOW;
if (CtrFlash<=TotalFlash) {
TimeTarget=TimeTarget+FlashOFF;
}
else {
TimeTarget=TimeTarget+Pause;
CtrFlash=1;
if (Status=="LD") {
Status="OF";
}
}
}
if (Status != "OF") {
digitalWrite(PinLed, Led);
}
else {
digitalWrite(PinLed, LOW);
}
}
if (CurrentTime>=NextSample) {
SensorValue = analogRead(A0);
Serial.println(Altitude);
Serial.println(Status);
Serial.println(InFlightFlag);
Altitude=102-SensorValue/10;
lcd.setCursor(11, 0);
lcd.print(Altitude);
if (Altitude<100) {
lcd.setCursor(13, 0);
lcd.print(" ");
}
if (Altitude<10) {
lcd.setCursor(12, 0);
lcd.print(" ");
}
if (Altitude>25) {
InFlightFlag=1;
}
AltitudeRangeInf=PrevAltitude-PrevAltitude*PercError/100;
AltitudeRangeSup=PrevAltitude+PrevAltitude*PercError/100;
if (Altitude<AltitudeRangeInf) {
Status="DN";
}
if (Altitude>AltitudeRangeSup) {
Status="UP";
}
if (Altitude>1&&AltitudeRangeInf<=Altitude && Altitude<=AltitudeRangeSup) {
Status="LV";
}
if (AltitudeRangeInf<=TargetAlti && TargetAlti<=AltitudeRangeSup) {
Status="TG";
}
if (InFlightFlag==1 && 1<=Altitude && Altitude<=5) {
Status="LN";
}
if (InFlightFlag==1 && Altitude<1 && Status != "OF") {
Status="LD";
}
if (InFlightFlag==0 && Altitude<1) {
Status="PF";
}
lcd.setCursor(3, 0);
lcd.print(Status);
NextSample=NextSample+SampleInterval;
PrevAltitude = Altitude;
}
lcd.setCursor(10, 1);
lcd.print(millis()/1000);
}
Paul_B
November 11, 2013, 10:10pm
4
Behaviour changes with the physical layout?
Put a 100 nF capacitor on the breadboard directly between pins 1 and 2 of your LCD.
system
November 11, 2013, 11:04pm
5
Paul__B:
Put a 100 nF capacitor on the breadboard directly between pins 1 and 2 of your LCD.
you mean, joining pins 1 & 2? Which should be + - on the display?
MarkT
November 13, 2013, 10:53pm
6
No, it goes between, a capacitor doesn't join signals, its an open circuit (at DC).
Hope that's clearer.
system
November 14, 2013, 8:44pm
7
Thank you very much Paul__B & MarkT
great suggestion, thank you very much
Bingo!
Ciao