Ja, habe ich.

Ich hab mir ein kleines Testprogramm geschrieben ...

Danke für Deine Hilfe, ich werde das heute Abend ausprobieren...

Wenn sich bis dahin noch nichts ergeben hat, kann ichs heute Abend ja mal mit meinen Modulen testen.

@MaFu: ich wollte nur fragen ob du das schon ausprobiert hast ... ?

Use an XOR function. (eg. 74LS86).

It works great for me, thanks!

Hi Everybody,

can I use the EthernetShield and the TLC5940 in one Project?
If yes which library will be the best for the TLC5940.


Thanks for help!

Why do you need an array with all the combinations?  You can tell which pins are high by looking at which bits of your byte are set (i.e. are 1).

if (_data & 1)
  // P0 is set

That is what I was looking for.
I do not know C and that's why I could not do that.
Tell me please how should I understand that: (_data & 1) // OK I already know....

And now, other way. I have 8 variables:

p1 = 1;
p2 = 1;
p3 = 0;
p4 = 0;
.
.
How to tell PCF8574 taht these pins (1,2,3,4) should be like 1,1,0,0....?

Thanks!

Hi,

I am reading the state of PCF8574 pins like this:

Code:

byte expanderRead() {
  byte _data;
  Wire.requestFrom(expander, 1);
  if(Wire.available()) {
    _data = Wire.receive();
  }
  
  return _data;
}

When:
P0 is HIGH I get 1
P1 is HIGH I get 2
P2 is HIGH I get 4
P3 is HIGH I get 8
.
.
.
P1 and P2 are HIGH I get 3

When only one pin is HIGH there is no problem - only 8 combinations.
When more pins are HIGH there is a problem - 256 combinations.
I need to create an array with all combinations!

Is there a simple method to read which pins are HIGH?

Thanks for help!

On the page you linked
Register 6 is the configuration for 8 I/O pins, register 7 for the 8 olthers pins.
So, you are sending the number 6 to the chip to tell it that you want to access the register number 6 (REGISTER_CONFIG = 6).

Now I understand...
but have one more question..

I've found a datasheet: http://www.datasheetcatalog.org/datasheet/philips/PCA9555_3.pdf
"... This register is an input-only port. It reflects the incoming logic levels
of the pins,..." (site 6)

if I understand I can not set all 16 pins as output or input?
Is there a I/O I2C chip where I can set all 16 pins how I want?

Thanks for help!

Hi,

I've found a great tutorial on:
http://www.neufeld.newton.ks.us/electronics/?p=241

but I have some questions:
(my questions as comments)

Code:

#define DIP_ADDRESS (0x4 << 3 | 0x0) // how should I understand that << and |
Wire.send(0xff & dir);  //  the same question with &
Wire.send(dir >> 8);    //  the same question with >>
//What make that three lines?

and one more question here:

Code:

#define REGISTER_CONFIG (6) // has REGISTER_CONFIG a value 6?
Wire.send(REGISTER_CONFIG); // why am I sending 6?

Thanks for Your help!

Thanks for the advice, mellis. Now there is a reference to this library at Arduino Playground, too.

Could You please show us the schema (circuit) how to connect all together?

After that look in the playground for some example I2C code and adapt that to this device.  As an example, here's a link to code for a digital compass using I2C.  This shows the basics of initialization, writing and reading.

Thanks, I am sure it will help me.

I've used a couple of these I2C LCD Controllers.  They are full featured and relatively inexpensive*.  Basically it's just a PIC with a customer firmware that emulates a LCD controller.

It looks nice, could you please show me a piece of code you are using with.
Do you use some library with it?

want to connect to my Arduino an alphanumeric LCD display via I2C Bus.

Why?  :-/

With I2C I need only two wires!
I want to buy 16x2 LCD display (without I2C) and some chip (I2C controller).
So it is cheaper.
But I need Know-how.

Hi,

I am new with Arduino and electronic too.
I want to connect to my Arduino an alphanumeric LCD display via I2C Bus.

Do you have any schema (circuit) how should I connect it, which controller (driver) should I use.
I was thinking about PCF7584 but I do not know...

So if you could help me...
Some examples of code, how to send words to lcd would be great too.

Thanks for your help!

HI,

i've tried to communicate between arduino and php. I used the php_serial class and it works great (linux server) with a simple instructions.

My goal is to control two or more output pins and read the input pins using php.
And now how i want to do this:

I send a string to arduino:'1;0;0;1' to set pin1:HIGH, pin2:LOW, pin3LOW, pin4:HIGH.
As response send arduino to php a string '1;1;0' what means pin5 is HIGH, pin6 is HIGH and pin7 is LOW.

 Do you think it is a good idea?
In php i will use the explode function to get an array from the string.
In Arduino i have to do the same, but c has no explode function, do you have any idea how to do this?

Thanks for help!

Did you install Wampserver?

Yes I did, unfortunately did not help.

Now I will use some other computer... I will let you know...