MicroPython • MP3-Player with Pico and DFPlayer Mini

Code:

import timefrom machine import Pinfrom dfplayermini import DFPlayerMiniimport random # For random song selectionplayer1 = DFPlayerMini(1, 4, 5)button1 = Pin(3, Pin.IN, Pin.PULL_UP)button2 = Pin(0, Pin.IN, Pin.PULL_UP)aux_detect = Pin(8, Pin.IN, Pin.PULL_UP)relay = Pin(9, Pin.OUT)S0 = Pin(6, Pin.OUT)S1 = Pin(7, Pin.OUT)S2 = Pin(10, Pin.OUT)x = 0y = 0relay_timer = 0 # Timer for BT changeoverrelay.value(0)switched = False # For AUX cable detectioncurrent_channel = 0# Mode variable (0 = sequence, 1 = shuffle)mode = 0current_song = 0 # Current song (for sequence mode)# Function for switching the multiplexer channeldef switch_channel(channel):    S0.value((channel >> 0) & 1)    S1.value((channel >> 1) & 1)    S2.value((channel >> 2) & 1)   switch_channel(0)read_value = player1.set_volume(15)read_value = player1.stop()# Check the buttonsdef check_buttons():    ““”Checks whether one of the buttons is pressed“””    if button1.value() == 0 or button2.value() == 0:        return True    return False   # Function for random playbackdef play_random():    ““”Plays a random song from the SD card“””    song = random.randint(1, 5) # Adjust the number of songs    print(f “Playing random song: {song}”)    player1.play(song)# Function for switching between sequence and shuffledef switch_mode():    global mode, current_song    if mode == 0: # Switch from sequence to shuffle        print(“Switching to shuffle mode”)        current_song = 0 # Reset the sequence number        play_random()        mode = 1    else: # Switch from shuffle to sequence        print(“Switching to sequence mode”)        mode = 0       # Function for playing the next song in sequence modedef play_next_in_sequence():    ““”Plays the next song in sequence“””    global current_song    current_song += 1    print(f “Playing next song in sequence: {current_song}”)    player1.play(current_song)   # Main loopwhile True:   # Check the AUX input    if aux_detect.value() == 0 and not switched:  # Check only if the cable is plugged in and has not yet been switched        print(“AUX cable plugged in”)        switch_channel(1) # Change channel        y = 1        switched = True # Set the variable to True to prevent the channel from being switched again        relay.value(0)        time.sleep(0.1)if aux_detect.value() == 1 and switched:  # Check whether the cable has been removed        switched = False # Allow switching again if the cable is removed        time.sleep(0.1)   # Check button 2 (AUX, BT, SD control)    if button2.value() == 0:        while button2.value() == 0:            pass        time.sleep(0.1)        if y == 0:            print(“AUX”)            switch_channel(1)            y = 1            time.sleep(0.2)        elif y == 1:            print(“BT”)            switch_channel(2)            relay.value(1) # Switch on relay            relay_timer = time.ticks_ms() # Reset timer when switching to BT            y = 2            time.sleep(0.2)        elif y == 2:            print(“SD”)            relay_timer = time.ticks_ms() # Reset timer when switching to BT            switch_channel(0)            time.sleep(1) # Wait 1 second before the song starts (wait for button press)            if check_buttons():  # Check whether a button has been pressed                print(“Action interrupted by button press”)            else:                read_value = player1.set_volume(15)                player1.play_next()            y = 0            time.sleep(0.2)                           # Monitor the timer to switch off the relay when 5 minutes have passed    if y != 2 and relay.value() == 1: # If the status is “SD” and the relay is on        if time.ticks_diff(time.ticks_ms(), relay_timer) > 3000: # 3 seconds for test purposes            print(“Deactivating relay due to inactivity.”)            relay.value(0) # Deactivate relay when 3 seconds have elapsed            time.sleep(0.1)                    # Check button 1 (play/pause and random mode)    if button1.value() == 0 and y == 0:        time.sleep(0.1) # Debounce        button1_time = time.ticks_ms()        click_count = 1 # Number of clicks       # Check for long press (> 1 second)        while button1.value() == 0:            if time.ticks_diff(time.ticks_ms(), button1_time) > 1000:                switch_mode() # Switch between modes                time.sleep(0.1)                break # No more multiple clicks possible                            # If no long press: Check for multiple clicks        else:            double_click_time = time.ticks_ms()            while time.ticks_diff(time.ticks_ms(), double_click_time) < 400:                if button1.value() == 0: # Second click recognized                    click_count += 1                    time.sleep(0.1) # Debounce again                    while button1.value() == 0:                        pass # Wait until released                    time.sleep(0.1) # Short debouncing after release                    if click_count == 2:                        double_click_time = time.ticks_ms() # Wait for third click                        continue                    if click_count == 3:                        print(“prev”) # triple click → “prev”                        time.sleep(0.1)                        break            else: # If there is no third click within the waiting time                if click_count == 2:                    print(“next”) # double-click → “next”                    if mode == 0:                        play_next_in_sequence()                    elif mode == 1:                        play_random() # Play random song in shuffle mode                                       elif click_count == 1:                    if x == 0:                        print(„play“)                        player1.start()                    else:                        print(„pause“)                        player1.pause()                    x = 1 if x == 0 else 0                           time.sleep(0.2) # Last Debouncing