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[on:]

Hey Arduinousers,

We have an old can machine which uses a NRI G13.6000 (flat cable ribbon serial) as a coin acceptor. Now I need to trick the machines relays board to think that a payment has been made.

The NRI has several output channels, but the one I need (channel 8) sends out a pulse to the board. I need to emulate that Pulse with the push of a button.

This is the description of the output channel of the NRI:

NPN 100ms 10mA active low w/ 47K pull-up to +5V

Is there anyone who knows how to pull this off?

Moderator edit: Smiley removed

[Reply #1 on:]

Do you want to learn to do it or do you want us to do it?

[Reply #2 on:]

Well even though it would be easier if someone did it, for me it would be better to learn it.

I've come up with this code:

Code:

void setup()

{

  pinMode(10, OUTPUT);   // PWM output right

}



void loop()

{

   analogWrite(10, 56);  // 56=111Hz ??


}

[Reply #3 on:]

// 56=111Hz

I don't really understand that.
PWM frequency is around 490Hz.
There's no need to set the pinMode for an analogWrite

[Reply #4 on:]

Yes and PWN is set between 0 and 255 right?

Zo 111Hz would be 56 value?

[Reply #5 on:]

No, PWM frequency is fixed, you vary the duty cycle (mark:space ratio) with the parameter to analogWrite

[Reply #6 on:]

Yep, but haven't I done that by giving analogWrite 56?

[Reply #7 on:]

You have varied the duty cycle, but the frequency remains the same, namely 490 Hz.

I don't see the significance of this 111Hz from what you've said so far.

Edit.
In case you don't understand the difference, consider a signal with one millisecond high, and nine milliseconds low. The frequency is 100Hz, and the duty cycle is 10%.
A signal with nine milliseconds high and one millisecond low has the same frequency, but a 90% duty cycle.

[Reply #8 on:]

I've read the output from the coin acceptor.

It's 100Hz normally and when you insert a coin it drops to 90Hz for a few milliseconds.

So I need to emulate this behaviour, from what I've read, PWM output should be the way to go.

[Reply #9 on:]

What I've done to get the values:

I've used pulseIn to read the pulse the coin acceptor generates:

Code:

void setup() {
  // initialize serial communication at 9600 bits per second:
  Serial.begin(9600);
  pinMode(pin, INPUT);
}



void loop()
{
  duration = pulseIn(pin, HIGH);
   Serial.println(duration);
   delay(50);
}

It gives a long list of

9960
9899
9927
9932
9966
9892

And when I enter a euro (coin acceptor) it gives:

9928
10098
10124
9831

[Reply #10 on:]

No, PWM is not the answer.
The PWM frequency is fixed unless you want to fiddle with registers.
Using micros () may be much simpler.
Have a look at blink without delay.

[Reply #11 on:]

So, normally I would have an interval of 9 milliseconds and on the push of a button it should need 10 milliseconds?

[Reply #12 on:]

No, 9 milliseconds would be closer to 111Hz.
11 milliseconds would be roughly to 90Hz.

The relationship is a reciprocal.

[Reply #13 on:]

My pulseIn program gave the following values:

around 10124 microseconds when euro has been inserted
around 9831 microsecond continuous so constant without euro.

So these are the values I have to use is 9.8 constant and then 10.12 when I insert a coin / push the button?

[Reply #14 on:]

As a side question, would it be possible to catch this on one pin (using pulsein) and then too just forward it to another pin with pulseout?