Recent Posts

Pages: [1] 2 3 ... 10

Thank you for your suggestions, I learn best by examples that are accompanied by insightful explanations. 

I searched the forum for details regarding Adding Hysteresis and none of it is sinking in...if you could show me how I could modify my code I will have a concrete example for future reference : )
General Electronics / Re: Arduino voltage drop
Last post by Paul__B - Today at 01:31 am

Not the best of pictures.

I think that "instructables" article has confused you somewhat.  It does contain some blunders but is modestly useful.  You can connect a relay module which contains a control transistor and possibly an opto-coupler, to an Arduino pin; you  cannot connect just the relay itself.

If you are going to attach modules - such as relays - to the Arduino, you need a 5 V power supply.  Powering from the USB port will work up to  a point, but you simply cannot use the on-board regulator to power any extra devices such as relay modules, it is unsuitable.

A common way to power something is to use a 5 V USB "phone charger" connected to the USB port.  This can supply up to 500 mA for the system.  This is limited not by the phone charger, but by the polyswitch protection device on the Arduino UNO.  If you need more current, you find a 5 V fully regulated power supply and connect it to all the devices requiring 5 V - including the Arduino itself via its 5 V pin.  Note, the Arduino is not supplying power, it is using it.
Deutsch / Re: Variable beim parsen nicht...
Last post by combie - Today at 01:27 am
Das kann doch nicht sein, in der seriellen Ausgabe ist ja das gleiche Problem, und die scrollt ja durch?!
Nagut ...
Dennoch buddelst du auf der falschen Baustelle. (?!?!?)

Code: [Select]

void setup()

  char number[] = "1572.0524017467";

void loop()

Programming Questions / Re: While loop
Last post by Due_unto - Today at 01:27 am
 while (bool z=true){  // assigns true to bool z, same as while(1), probably not what you intended
 while (bool z==true){ // compares bool z to true, probably what you really wanted

Has or can anyone try this circuit? Its not working for me. The LED doesnt light up when I plug the power in. I checked the LED and it works fine. I switched to other 2n2222 transistors and other 3906 and another electrolytic 22uF cap thinking I might have burnt out my original ones while testing but stil nothing.

I got it from here:

Im unsure about the connection of the cap and LED. Wondering if my leads are connected in the right order.
General Electronics / Project02 Spaceship Interface
Last post by DreamZ - Today at 01:19 am
int switchState = 0;

void setup() {



void loop() {
switchState = digitalRead(2);

if (switchState = LOW){
 digitalWrite(3,HIGH); //green

  delay(250); // ms

  digitalWrite(5,LOW );


Can anyone tell me why my circuit doesn't work? It just blinks the 2 red light.
Programming Questions / While loop
Last post by Nikosant03 - Today at 01:18 am
Hi everyone,

Can someone tell me why in this piece of code I cannot exit the while loop?

Code: [Select]
void loop(){
 char key = keypad.getKey();
 while (bool z=true){
key = keypad.getKey();
  if(key=='1' || key=='2' || key=='3' || key=='4'){


LEDs and Multiplexing / Re: Four Reed Switches Input f...
Last post by Wawa - Today at 01:18 am
int switch1=1;

Pin1 is the TX pin of an Uno, and is already used by the USB<>Serial chip.

If you run out of digital pins, then use the analogue pins.
A0-A5 are just digital pins with the added functionality of analogue-in.

int switch1 = A0;
int switch1 = 14; // ok on an Uno
or, better (less memory use)
const byte switch1 = A0; // value is never changed
Project Guidance / Re: raspberry pi
Last post by Grumpy_Mike - Today at 01:16 am
is the version of the arduino ide on the raspberry pi still usable as it is an older version
Project Guidance / Re: raspberry pi
Last post by Railroader - Today at 01:13 am
Why not use the latest corresponding version from Arduino?
Pages: [1] 2 3 ... 10