...is this your first day on the internet?

Less than a day for me, but in the measure of you earthlings this is more than a century 

Seriously: I looked at amazon and in local toy stores. I'm not sure, if a server can move the load; and I have to convince my "secretary of finances" - these are quite expensive (especially for a first project).

...
OTOH, I keep thinking I could do it all with 2 wide-beam sonars [40-deg each], and mount
them so as to have a small degree of overlap on the center edge of the beams. That way, 
only one sonar would pick up an object moving in from the periphery, and would trigger
the servo to move them until both picked up the moving object simultaneously. Then, as
the object moved around, it would move out of one of the beams, and cause the servo
to move to track it.
...

I think this could be easier and more exact. Thanks!

And thanks for the two links.

best regards
Andreas

Hi *,

for a (perhaps silly  ) project I need some advice for the selection of distance sensors. I'll try to explain:

This should be a sort of a head (my first idea was a skull of a dinosaur, but this is difficult to find), which is mounted onto a server to follow people (colleagues  ]) - and perhaps light some LEDs in the eyes, if they approach. So I thought of three distance sensors: one in the viewing direction, the two left and right with an angle of (perhaps) 30° or 45°. So if one of the outer sensors receives a smaller distance, the servo turns the head until the middle sensor has this distance (or nearly this distance). All this stuff shall sit on my desk. The possible distances are between 50 cm and 2 m (or 150 cm - I'm not quite sure). So, what is the better choice: IR distance sensors (e.g. Sharp GP2-0215) or ultra sonic (e.g. SRF 05)?

And for another project: how can I detect motion throw a window? I think ultra sonic sensors will not work. Does IR work?

best regards
Andreas

cannot convert 'String' to 'const char*' for argument '1' to 'int strcmp(const char*, const char*)'

OK, OK: die Klasse String ist nicht das gleiche wie ein C-Zeichenkette (die i.W. ein Pointer auf char ist  ) Dann bleibt nur eine Methode aus der Klasse String - und da hat Dir Mario ja schon einen Pointer gegeben.

Andreas

Du vergleichst hier keine Zeichenketten, sondern Zeiger auf die Speicherstellen, in denen die Zeichenketten gespeichert sind (ja: das ist C  ).
strcmp ist hier Dein Freund:

Code:

if (strcmp (inputString, "P1") == 0) ...

usw.

viele Grüße
Andreas

@Techone: many thanks for the links; a lot to read for a beginner like me!

Andreas

...
Then when all is tested I pop out the programmed 328p chip and build it into the permanent project adding what few support components the 328p needs to operate with, crystal some caps, a pull-up resistor, etc.
...

Hi,

do you have more information what are the needed components? (Or links?) And how do I start with a fresh 328p on the arduino?

best regards
Andreas

Thanks to all and a special thank to Nick for the link!

best regards
Andreas

Oder auch (gerade im Cookbook gelesen):

Code:

String data [] = parameter.split ('&');

viele Grüße
Andreas

Vielleicht kannst Du mit strtok oder strtok_r was anfangen. Und dafür am Anfang des Sketches nicht

Code:

#include <string.h>

vergessen!!

viele Grüße
Andreas

First: Thanks to all for the answers.

What other sketch? A sketch you upload stays there until you upload a different one. Even after you power it off.

I had a sketch, which handled a servo and an ultra sound device (let's call it "ultra sound radar"  ). After disconnecting these devices and connecting RGB LEDs for the next test, I connected the Arduino to the computer to upload the RGB sketch, but during the time between USB connection and uploading the new sketch the "radar sketch" was running for a short time (an a LED started glowing). This was the reason for my question. It seems that I have to be careful.

That is why I always down load the basic sketch before connecting and hardware to the arduino as you never know what was there the last time.

OK - will do my very best to follow this advice.

best regards
Andreas

Hi Grumpy_Mike,

thanks for the answers!

you can't damage the chip by programming it wrong.

Well you can if you have an output feeding into an arduino input and you program that pin to be an output. If then the external output and the arduino one are different levels you can damage the arduino pin.

With "other level" do you mean other voltage? So if I have only 5V everywhere can that be OK?

best regards
Andreas

Hi majenko,

thanks for the quick answer - this takes some anxiety from me. I thought more this:


 

I'm curious when I will connect a LED to 9V for the first time 

best regards
Andreas

Hi *,

did I introduced myself? My name is Andreas, I live in Germany and earn my life as application administrator. Some months ago I found my passion for robots and then mikrocontrollers. But the environment with ISP and so is (still) a little bit complicated for me  . So I searched for an alternative and stumbled over Arduino. After gambling around with LEDs, RGB LEDs, sensors and servo I stumbled over following:
I had a sketch for a sort of ultra sound radar (SRF05 and servo). Then I demounted this and built up two RGB LEDs to test them; after writing the new sketch I connected the Arduino to upload it, but the other sketch started running.

So my question is: can I damage the arduino or the connected hardware by using a "wrong" sketch for the hardware?

best regards
Andreas

Moin da_user,

1. probier doch mal einen völlig anderen Font (rein testhalber). Es kann sein, dass Windows den "Monospace" auf "Courier New" mappt. ("Monospace" ist eher eine Klasse von Fonts.)

2. Beachte doch mal ganz genau, wie Du Strg-Shift-M drückst  . Strg-M gibt den Zeilenvorschub, und das anschließende Shift öffnet dann die Konsole.

viele Grüße
Andreas

i would do this with the built in reset button.

Perhaps: use the EEPROM. In the setup routine read the value from EEPROM (if it exists), increment it and store it back. In this way you can count the "boot events".

The reset button is connected to the reset pin on the µC, so you cannot use it as a "normal" button.

best regards
Andreas