We get fake long pressed buttons when conect device to PI.

[shuricksumy]

Hi,
on my PI I very often get fake long pressed buttons. It happens when I connect devices, like usb flash drive. I analyzed issue. To my mind, the main reason is electromagnetic interference. The signal causes GPIO.add_event_detect and after that very quickly set GPIO.input(channel) == 1. The self.down_time_previous has previos value (from last call of function) - as result we get long press button. I changed code (ex: volume down button):

longpress_time = 1
longpress_time2 = 5

def vol_down(self, channel):
if GPIO.input(channel) == 1:
if self.down_time_vol_down + longpress_time > time.time():
self.frontend.input({'key': 'volume_down', 'long': False})
elif self.down_time_vol_down + longpress_time2 > time.time():
self.frontend.input({'key': 'volume_down', 'long': True})
else:
self.down_time_vol_down = time.time()

Now I don't get fake long pressed buttons. Please, check it and fix.

[ghost]

Please next time use this for commenting code as in python indentation is essential:

Your code

This is how I am interpreting your code (Tell me if I am interpreting wrong):

longpress_time = 1
longpress_time2 = 5

def vol_down(self, channel):
    if GPIO.input(channel) == 1:
        if self.down_time_vol_down + longpress_time > time.time():
            self.frontend.input({'key': 'volume_down', 'long': False})
        elif self.down_time_vol_down + longpress_time2 > time.time():
            self.frontend.input({'key': 'volume_down', 'long': True})
    else:
        self.down_time_vol_down = time.time()

I am not able to reproduce the error as I am using a powered USB hub. Without the hub the pi reboots when I insert a USB.

So to be sure if I understood this correctly. The problem is that when you plug a USB, GPIO value changes so fast that GPIO.input(channel) is never 0 and down_time is not updated. So as the down time is a old value longpress is triggered.

To fix that your idea is that it should be a max time (5 seconds in your example) for a button press and that we should ignore that press as it will probably be a false positive.

Another fix I think of could be to check if the time has been updated:

def vol_down(self, channel):
    if GPIO.input(channel) == 1:
        if self.down_time_vol_down >= 0:
            if self.down_time_vol_down + longpress_time > time.time():
                self.frontend.input({'key': 'volume_down', 'long': False})
            else:
                self.frontend.input({'key': 'volume_down', 'long': True})
        self.down_time_vol_down = -1
    else:
        self.down_time_vol_down = time.time()

Please try this code and reply if it fixes or not.

Thanks for your help in making mopidy-ttspio better!

[shuricksumy]

Hi,
you interpreted correctly my code. I checked your code. It worked good. But when we start mopidy the variables are declared with value = 0. And we get fake pressed buttons only one time. So we should use next:

    self.down_time_previous = -1
    self.down_time_next = -1
    self.down_time_main = -1
    self.down_time_vol_up = -1
    self.down_time_vol_down = -1

Thanks for your help too.

[ghost]

Thanks for the feedback!

The fix will be included in next release