One button to have two values.

Hi everyone. Im very much new to this forum and would really appreciate to have help all around.

Im doing a project with C language to control a radio using a remote control. I generally have 5 buttons on the remote of which 1 of the buttons need to have a single press (mute function) and a long press (turn ON/OFF) as well.

The problem that I am currently facing is that although I've tried to do several ways, such as for loops, while loops, if else etc.. but non works.

It seems that it always goes into the else if loop instead of if and/or else, even though the counter is set at the correct number.

---

Code:

---

void construct(void)
{
#if 1   
        //assuming all variables are properly declared in unsigned char
    {   
        if ((key > 205) && (key < 235))                //button 1
        {
            count++;
            if ((count > 1) && (count <= 51))        //short press
            {
                d1 = 0xXX;                       
                d2 = 0xYY;
            }
            else if ((count > 51) && (count <=255))    //long press
            {
                d1 = 0xXX;                       
                d2 = 0xYY;
            }
            else
            {
            }
        }
        else if ((key > 155) && (key < 173))        //button 2
        {
            d1 = 0xXX;                       
            d2 = 0xYY;       
        }
        else if ((key > 80) && (key < 141))            //button 3
        {
            d1 = 0xXX;                       
            d2 = 0xYY;                           
        }
        else if ((key > 47) && (key < 78))            //button 4
        {
            d1 = 0xXX;                       
            d2 = 0xYY;                               
        }
        else if ((key >= 0) && (key < 15))            //button 5
        {
            d1 = 0xXX;                       
            d2 = 0xYY;                           
        }
        else
        {   
        }
    }
       
#endif
}

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[ATTACH]12369


Could anyone please help and see if there is anything that I missed?

gumasumnida.:o

You need key-down and key-up events if you want to distinguish short-press from long-press.

Where are you getting key presses from?

Which OS/Compiler are you using?

Is this being run on your desktop development machine, or some kind of dev board?

Hi Salem,

key presses are obtained from ADC conversion (the key value ranges are the converted values). Im using Microchip pic 10F222 running on MPLAB IDE v8.87.

So what value is stored in key when the key is up?

How is construct() called? Is it in a loop in your main(), or is it called directly as a result of a completed ADC conversion event?

Finite-state machine - Wikipedia, the free encyclopedia
Basically, you have two events, key-press and key-release
You also have two states key-up and key-down
So state=key-up and event=key-press takes you to state key-down.

In state key-down, you increment your counter (at some rate).

On the key-release event, you look at the key and the counter, and decide what it all means.

Quote:

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Originally Posted by kim15

It seems that it always goes into the else if loop instead of if and/or else, even though the counter is set at the correct number.

---

Just from the code you provided, it's probably impossible to give an accurate answer. For example, where are you initializing count? Do you ever reset count back to 0?

Run the code using a debugger and set a breakpoint right after the "count++" line. Then observe if your supposition is correct.

Quote:

---

Basically, you have two events, key-press and key-release
You also have two states key-up and key-down
So state=key-up and event=key-press takes you to state key-down.

---

How exactly do u do a key state events?

Thanks

Quote:

---

Originally Posted by kim15

How exactly do u do a key state events?

Thanks

---

The easiest way of doing this is with a switch statement

Code:

---

switch (state)
{
  case 0:
    if (button_pressed)
    {
      count += (count < 100);
      if (count == 100)
      {
        count = 0;
        state = 1;
      }
      else if (count > 100)
      {
        count = 0;
      }
    }
    else
    {
      count = 0;
    }

    break;

  case 1:
    if (!button_pressed)
    {
      count += (count < 100);
      if (count == 100)
      {
        count = 0;
        state = 0;
      }
    }
    else
    {
      count = 0;
    }

    break;
   
}

---

Also noticed that I do not take the reading straight away -> I wait for 100 positive readings in a row before I change state.

Thanks Click_Here! It was really helpful.

I managed the key state events as above. However, I seem to notice that my key state never enters case 1 for high (mine is low trigger) even pressing the key multiple times. Is there a reason why?

Thanks in advance

Do you have a pull up resister on the port, or have you enabled the weak pull ups?

Do you have an output LED which you could use for debugging? - i.e. Turn output on when entering the 'if' statement. I'd check to see if the port is set up by temporarily putting something like this in the code

Code:

---

for(;;)
{
  if(input_latch == 0)
  {
    LED_output_pin == 1;
  }
  else
  {
    LED_output_pin == 0;   
  }
}

---

It will loop there forever, changing the output the same as the button -> If this doesn't work, you have a set-up problem

Have you correctly set-up the tristate register for input (TRISGPIO)?

What GPIO are you using? For digital mode on the 10F222 for each pin, you need to make sure other peripherals are not turned on -
GP0 - ANS0 needs to be cleared
GP1 - ANS1 needs to be cleared
GP2 - FOSC4 and T0CS need to be cleared
GP3 - MCLRE needs to be cleared

What actual compiler are you using? C18/HI-TECH/CCS/...

Initially my input is configured as analog (obtained from the analog key) then is converted into digitial via ADC. Im not sure entirely what you mean by clear the pins.

My input pin is : GP0
Output pin (digital): GP1
My GP2 isnt connected (not using, I assume it should be 0 at this point?)
On my GP3, i use it as my pull-up resistor with 100k ohm.

For the TRISGPIO, yes, I have set it up correctly, because before the hacking, the remote is successfully working..


Appreciate all the help. Thanks in advance.

I reread your post an saw that you are dealing with an analogue input - I am imagining something like this Save Pic Pins with a 1 pin analog hex keypad but simpler.

OK, so...

Have you tested the analogue input with a variable resister input? You can still use an LED for debugging...

What signal conditioning are you doing on the input? (Have you got an RC circuit, or are you taking the average input, ect...) - You shouldn't trust the first value you get from your analogue input. Don't forget about rise time considerations with the input signal.

Have you considered using something like the MCP23X08? http://ww1.microchip.com/downloads/e...tes/00972a.pdf

I might comment on the states that you might have as well...

state 0
- If input detected, state = 1

state 1
- Input is detected. If input stays in this range for, say, 1000 readings, output = key1, state = 6
If input voltage is larger than the voltage range for key1, state = 2
If input voltage is smaller than this voltage range for key1, state = 0

state 2
- If input stays in this range for, say, 1000 readings, output = key2, state = 6
If input voltage is larger than the voltage range for key2, state = 3
If input voltage is smaller than this voltage range for key2, state = 1

state 3
- If input stays in this range for, say, 1000 readings, output = key3, state = 6
If input voltage is larger than the voltage range for key3, state = 4
If input voltage is smaller than this voltage range for key3, state = 2

state 4
- If input stays in this range for, say, 1000 readings, output = key4, state = 6
If input voltage is larger than the voltage range for key4, state = 5
If input voltage is smaller than this voltage range for key4, state = 3

state 5
- If input stays in this range for, say, 1000 readings, output = key5, state = 6
If input voltage is smaller than this voltage range for key3, state =

state 6
- Print output key
State = 7

state 7
- If input voltage 0 again, state = 0

Quote:

---

Originally Posted by Click_here

Have you tested the analogue input with a variable resister input? You can still use an LED for debugging...

What signal conditioning are you doing on the input? (Have you got an RC circuit, or are you taking the average input, ect...) - You shouldn't trust the first value you get from your analogue input. Don't forget about rise time considerations with the input signal.

Have you considered using something like the MCP23X08? http://ww1.microchip.com/downloads/e...tes/00972a.pdf

---

Hey, thanks for the quick response.

Im not so sure where I am to start, so I'll just start from beginning. So... The remote has 5 different buttons that have different values for the resistors. after converting it, i get the ranges for the key (that is obtained from ADC). I gave about 10 percent tolerance for each key pressed. After reading and determining which key was pressed, it will then start to send out the data 8bit by 8bit.

Tried it out, and the remote works fine. It does what it basically supposed to do with the values for each d1 and d2. Then a situation comes where I need to make one of the buttons (button one) to have 2 types of presses; short press and long press, which has 2 different set of values for d1 and d2.

Now, I have tried using if else. Sometimes it works, sometimes it doesnt. But that isnt the point; the point is that in order for me to access the long press, i first must access to the short press. Which is inconvenient since I dont want the button to be sending the data d1 and d2 for the short press while intending for the long press.

Then when Salem suggested to use key state, and by using the method that you gave (switch case) I wrote the code just a little different. That is by using the states for the key states to determine the short and long press.

key_state == 0 means it is short press (not pressing after several count) and key_state == 1 means long press (still pressing after several count)

But the output seems to only detect the key_state == 0 and never the key_state == 1. Even when I had first initialized the value to be 1 instead of the norm 0.

I've included the key state events that you suggested. Did I miss something else?

Please advise.

Thanks

Looking at the states I gave before, what you could do is is key0 has been pressed, don't send output right away -> Go to a new state that increments a variable while button is pushed down. When the button's release is detected, see how many cycles have occurred -> If the number of cycles is larger than 'n', output = key0a, otherwise, output = key0b. state = 7 to print. I would then switch the release/print order like this:

state 0
- If input detected, state = 1


state 1
- Input is detected. If input stays in this range for, say, 1000 readings, state = 8
If input voltage is larger than the voltage range for key1, state = 2
If input voltage is smaller than this voltage range for key1, state = 0


state 2
- If input stays in this range for, say, 1000 readings, output = key2, state = 6
If input voltage is larger than the voltage range for key2, state = 3
If input voltage is smaller than this voltage range for key2, state = 1


state 3
- If input stays in this range for, say, 1000 readings, output = key3, state = 6
If input voltage is larger than the voltage range for key3, state = 4
If input voltage is smaller than this voltage range for key3, state = 2


state 4
- If input stays in this range for, say, 1000 readings, output = key4, state = 6
If input voltage is larger than the voltage range for key4, state = 5
If input voltage is smaller than this voltage range for key4, state = 3


state 5
- If input stays in this range for, say, 1000 readings, output = key5, state = 6
If input voltage is smaller than this voltage range for key3, state = 4


state 6
- If input voltage 0 again, state = 0
State = 8


state 7
if voltage not 0, increment a variable.
if voltage is 0 -> if variable > 1000000, output = key0a, else output = key0b, state = 8

state 8
- Print output key
- state = 0

Quote:

---

Originally Posted by Click_here

What signal conditioning are you doing on the input? (Have you got an RC circuit, or are you taking the average input, ect...) - You shouldn't trust the first value you get from your analogue input. Don't forget about rise time considerations with the input signal.

---

You can trust analog input as long as the ADC polling rate is slow enough. The ADC will poll the analog signal, and average it for a short time before setting the output register. So there isn't necessarily a need for digital averaging.

Quote:

---

Originally Posted by King Mir

You can trust analog input as long as the ADC polling rate is slow enough. The ADC will poll the analog signal, and average it for a short time before setting the output register. So there isn't necessarily a need for digital averaging.

---

Can you tell me where you have got this information about the PIC10F222?

I've never heard or read about any automatic averaging done with this device.

Quote:

---

Originally Posted by kim15

Hey, thanks for the quick response.

Im not so sure where I am to start, so I'll just start from beginning. So... The remote has 5 different buttons that have different values for the resistors. after converting it, i get the ranges for the key (that is obtained from ADC). I gave about 10 percent tolerance for each key pressed. After reading and determining which key was pressed, it will then start to send out the data 8bit by 8bit.

Tried it out, and the remote works fine. It does what it basically supposed to do with the values for each d1 and d2. Then a situation comes where I need to make one of the buttons (button one) to have 2 types of presses; short press and long press, which has 2 different set of values for d1 and d2.

Now, I have tried using if else. Sometimes it works, sometimes it doesnt. But that isnt the point; the point is that in order for me to access the long press, i first must access to the short press. Which is inconvenient since I dont want the button to be sending the data d1 and d2 for the short press while intending for the long press.

Then when Salem suggested to use key state, and by using the method that you gave (switch case) I wrote the code just a little different. That is by using the states for the key states to determine the short and long press.

key_state == 0 means it is short press (not pressing after several count) and key_state == 1 means long press (still pressing after several count)

But the output seems to only detect the key_state == 0 and never the key_state == 1. Even when I had first initialized the value to be 1 instead of the norm 0.

I've included the key state events that you suggested. Did I miss something else?

Please advise.

Thanks

---

That won't work, you need at least one more bit of state or data. You need to be able to distinguish between when the button was just pressed, and when the button is pressed then let go.

I would do something like this:

Code:

---

old_data= data;
data = get_button();
if(old_data == LONG_OR_SHORT_BUTTON){
  if(old_data == data)
    send_long_option()
  else
    send_short_option()
}
switch(data){
  other buttons

}

---

Now you do need to make sure with the above that if the person switches between LONG_OR_SHORT_BUTTON to another button, something appropriate happens.

Also the above code assumes that get data is a blocking call on the ADC, and that the ADC has a slow enough polling time. If it doesn't you can do digital averaging to make it work as if it was.

Quote:

---

Originally Posted by Click_here

Can you tell me where you have got this information about the PIC10F222?

I've never heard or read about any automatic averaging done with this device.

---

EDIT: You're right, this chip has a fixed clock. There is necessarily automatic averaging in the ADC, but you can't vary the polling period.

The acquisition time is to compensate for impedance that slows down charging the "charge hold capacitor", as described in section 7.9 of the data sheet - Not for filtering. The inaccuracies will come from noises on the line - Read here for more info on the noises you need to watch out for http://ww1.microchip.com/downloads/e...tes/00823a.pdf

Where are you getting the automatic averaging from?

I've modified the program a little. I have one additional function (key_states() that calls for the states for each keys pressed). Both of construct() and key_states() functions are called in main().

Code:

---

main(void)
{
    system_init();
    while(1)
    {
        if ((key > 205) && (key < 235))
        {
            pressed = 1;
        }
        else
        {
            pressed = 0;
        }
        key_states ();
        construct();               
    }                                   
}



void construct(void)
{
    {   
        if ((key > 205) && (key < 235))   
        {
            if (key_state == 0)
            {
                if (!long_press)
                {
                    /* short - Mute function */
                }
                else
                {
                    /* Long - On/Off function */
                    long_press = 0;
                }
            }
        }   
        else if ((key > 155) && (key < 173))       
        {
            /* button 2 */
        }
        else if ((key > 80) && (key < 141))           
        {
            /* button 3 */
        }
        else if ((key > 47) && (key < 78))   
        {
            /* button 4*/
        }
        else if ((key >= 0) && (key < 15))   
        {
            /* button5 */
        }
        else
        {   
            /* null*/
        }
    }
       
#endif
}


void key_states ()
{
    switch (key_state)
        {
            case 0:
            {
                /* initial state */
                if (pressed)
                {
                    count=1;
                    key_state = 1;
                }
                break;
            }


            case 1:
            {
                if (pressed)
                {
                    count++;
                    if (count > 10)
                    {
                        /* long */
                        long_press = 1;
                        count = 0;
                        key_state = 0;
                    }
                }
                else
                {
                    if (count < 5)
                    {
                        /* short */
                        long_press = 0;
                    }
                    else
                    {
                    }
                    count = 0;
                    key_state = 0;
                }
                break;
            }
            default:;
        }
}

---

In this recent code, I still get the same error! It just doesnt get into the long press for button 1 (which is marked as ON/OFF function in construct() function)

Could you please help to look into it? I have run simulation on this, where I hard code key = 220 (that replicates the ADC result) to see if the functions are functioning well or not. Through the simulation, it seems to be alright. But once tested, it doesnt seem to be so.

:(:(:(:(:(