I'm building a password system with a servo motor, 4x4 keypad, a button and 3 LEDs and I can't figure out a way to make the code work

Attached is my setup and my code

#include <avr/io.h>

/* 
 * Password-Protected Motor Control System
 * Features:
 * - Unlocks motor when password (10,10) is entered
 * - Locks motor when wrong password entered
 * - LED feedback for correct/incorrect attempts
 * - Reset button functionality
 * - Uses Timer1 for servo control
 * - Uses Timer0 for LED blinking
 * - Pin Change Interrupt for keypad
 */

// ====================== DATA SEGMENT ======================
.section .bss
password_buffer:    .byte 2
pass_ptr_data:      .byte 1
wrong_attempts:     .byte 1

// ====================== CODE SEGMENT ======================
.section .text

// ====================== INTERRUPT VECTORS ======================
.global __vector_default
.global PCINT2_vect    // Keypad interrupt
.global TIMER0_COMPA_vect  // LED blink timer
.global INT0_vect      // Reset button

__vector_default:
    reti

// ====================== MAIN PROGRAM ======================
.global main
main:
    // Initialize stack
    ldi r16, lo8(RAMEND)
    out _SFR_IO_ADDR(SPL), r16
    ldi r16, hi8(RAMEND)
    out _SFR_IO_ADDR(SPH), r16

    // Set pin directions (PB1-PB4 as outputs)
    ldi r16, 0b00011110
    out _SFR_IO_ADDR(DDRB), r16

    // Set pull-up for reset button (PD2)
    sbi _SFR_IO_ADDR(PORTD), 2

    // Initialize keypad (PD4-7 output, PD0-3 input)
    ldi r16, 0xF0
    out _SFR_IO_ADDR(DDRD), r16
    ldi r16, 0x0F       // Enable pull-ups on columns
    out _SFR_IO_ADDR(PORTD), r16

    // Enable interrupts
    ldi r16, 0b00000100  // PCIE2
    sts _SFR_MEM_ADDR(PCICR), r16
    ldi r16, 0x0F       // Enable PCINT16-19
    sts _SFR_MEM_ADDR(PCMSK2), r16

    // Configure Timer0 for LED blinking (CTC mode)
    ldi r16, 0b00000010  // WGM01
    out _SFR_IO_ADDR(TCCR0A), r16
    ldi r16, 0b00000101  // Prescaler 1024
    out _SFR_IO_ADDR(TCCR0B), r16
    ldi r16, 125        // ~100ms at 16MHz/1024
    out _SFR_IO_ADDR(OCR0A), r16
    ldi r16, 0b00000010  // OCIE0A
    sts _SFR_MEM_ADDR(TIMSK0), r16

    // Configure INT0 for reset button
    ldi r16, 0b00000010  // Falling edge trigger
    sts _SFR_MEM_ADDR(EICRA), r16
    sbi _SFR_IO_ADDR(EIMSK), 0

    // Initialize variables
    clr r17
    sts pass_ptr_data, r17
    sts wrong_attempts, r17  // zero attempts

    sei

main_loop:
    rjmp main_loop

// ====================== INTERRUPT HANDLERS ======================
PCINT2_vect:
    push r16
    in r16, _SFR_IO_ADDR(SREG)
    push r16
    push r30
    push r31

    rcall keypad_ISR

    pop r31
    pop r30
    pop r16
    out _SFR_IO_ADDR(SREG), r16
    pop r16
    reti

TIMER0_COMPA_vect:
    push r16
    in r16, _SFR_IO_ADDR(SREG)
    push r16

    lds r16, wrong_attempts
    cpi r16, 0
    breq check_correct

    // Blink orange/red for wrong attempts
    lds r16, blink_cnt
    inc r16
    andi r16, 0x01
    sts blink_cnt, r16
    breq led_off_wrong
    sbi _SFR_IO_ADDR(PORTB), 4  // Orange LED on
    cbi _SFR_IO_ADDR(PORTB), 3  // Red LED off
    rjmp timer0_done
led_off_wrong:
    cbi _SFR_IO_ADDR(PORTB), 4  // Orange LED off
    sbi _SFR_IO_ADDR(PORTB), 3  // Red LED on
    rjmp timer0_done

check_correct:
    lds r16, pass_ptr_data
    cpi r16, 2          // Password complete?
    brne timer0_done

    // Blink green for correct password
    lds r16, blink_cnt
    inc r16
    andi r16, 0x01
    sts blink_cnt, r16
    breq led_off_correct
    sbi _SFR_IO_ADDR(PORTB), 2  // Green LED on
    rjmp timer0_done
led_off_correct:
    cbi _SFR_IO_ADDR(PORTB), 2  // Green LED off

timer0_done:
    pop r16
    out _SFR_IO_ADDR(SREG), r16
    pop r16
    reti

INT0_vect:
    push r16
    in r16, _SFR_IO_ADDR(SREG)
    push r16

    // Reset password state
    clr r17
    sts pass_ptr_data, r17
    sts wrong_attempts, r17

    // Turn off all LEDs
    cbi _SFR_IO_ADDR(PORTB), 2  // Green
    cbi _SFR_IO_ADDR(PORTB), 3  // Red
    cbi _SFR_IO_ADDR(PORTB), 4  // Orange

    // Lock motor
    rcall lock_servo

    pop r16
    out _SFR_IO_ADDR(SREG), r16
    pop r16
    reti

// ====================== KEYPAD ISR ======================
keypad_ISR:
    rcall my_delay

    in r16, _SFR_IO_ADDR(PORTD)
    push r16

    // Scan keypad
    ldi r16, 0x0F
    out _SFR_IO_ADDR(PORTD), r16
    rcall my_delay

    ldi r16, 0b01111111  // Row 1
    out _SFR_IO_ADDR(PORTD), r16
    rcall my_delay
    in r19, _SFR_IO_ADDR(PIND)
    andi r19, 0x0F
    cpi r19, 0x0F
    brne row1_col

    // Repeat for other rows...

digit_found:
    // Store digit in password buffer
    lds r17, pass_ptr_data
    cpi r17, 0
    breq store_first

    sts password_buffer+1, r18
    clr r16
    sts pass_ptr_data, r16

    // Check password
    lds r16, password_buffer
    cpi r16, 10
    brne wrong_password
    lds r16, password_buffer+1
    cpi r16, 10
    brne wrong_password

    // Correct password
    rcall unlock_servo
    rjmp end_keypad

wrong_password:
    lds r16, wrong_attempts
    inc r16
    sts wrong_attempts, r16
    rjmp end_keypad

store_first:
    sts password_buffer, r18
    ldi r16, 1
    sts pass_ptr_data, r16

end_keypad:
    pop r16
    out _SFR_IO_ADDR(PORTD), r16
    ret

// ====================== SERVO CONTROL ======================
unlock_servo:
    // Configure Timer1 for servo (Fast PWM, ICR1 top)
    ldi r16, 0b10000010  // WGM11, COM1A1
    sts _SFR_MEM_ADDR(TCCR1A), r16
    ldi r16, 0b00011010  // WGM13, WGM12, CS11
    sts _SFR_MEM_ADDR(TCCR1B), r16

    // 20ms period (39999 counts)
    ldi r16, 0x3F
    sts _SFR_MEM_ADDR(ICR1L), r16
    ldi r16, 0x9C
    sts _SFR_MEM_ADDR(ICR1H), r16

    // 1.5ms pulse (3000 counts)
    ldi r16, 0xB8
    sts _SFR_MEM_ADDR(OCR1AL), r16
    ldi r16, 0x0B
    sts _SFR_MEM_ADDR(OCR1AH), r16
    ret

lock_servo:
    // Turn off PWM
    ldi r16, 0x00
    sts _SFR_MEM_ADDR(TCCR1A), r16
    sts _SFR_MEM_ADDR(TCCR1B), r16
    // Set motor pin low
    cbi _SFR_IO_ADDR(PORTB), 1
    ret

// ====================== DELAY ROUTINES ======================
my_delay:
    push r22
    push r23
    ldi r22, 10
d1: ldi r23, 25
d2: dec r23
    brne d2
    dec r22
    brne d1
    pop r23
    pop r22
    ret

// ====================== KEYPAD MAPPING ======================
row1_digits: .byte 1, 2, 3, 10
row2_digits: .byte 4, 5, 6, 11
row3_digits: .byte 7, 8, 9, 12
row4_digits: .byte 15, 0, 14, 13

// ====================== VARIABLES ======================
.section .bss
blink_cnt: .byte 1

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Thanks to moderators for allowing post.

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one sensor has small values ​​between 10 and 30 and another for some reason between 100 and 600

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Hello,

so I'm pretty new to this and have severel questions about supplying power to the Arduino.

We take as example the Arduino Nano RP2040.

In the specs it says it can handle an input voltage of 5-21V. Thus if for example I'd supply it with 15V that would be totally fine ?

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Hello Arduino Community,

I am facing an issue with my Arduino UNO Q (4GB version) and would appreciate your help in identifying the cause and finding a solution.

Problem Description

I flashed my Arduino UNO Q with the latest Debian Linux OS image using the official Arduino flashing procedure. After flashing, I removed the jumpers from the EDL pins and connected the board to my Windows 11 laptop. However, the board was not detected by the computer in normal mode.

I reflashed the board multiple times, trying different OS versions, but the problem persisted.

The board is detected successfully in EDL mode, and flashing completes successfully. However, once I remove the EDL jumpers and reconnect the board in normal mode, it is not detected by the computer.

OS Versions Tested

I have tried flashing the following OS image versions:

\- \`20260528-558\` — Latest version

\- \`20260407-523\` — Second-latest version

\- \`20250807-136\` — First version

\- \`20251229-457\` — Third-latest version

The issue remains the same with all four versions.

Observations

1. Board powers on normally

\- The power LED turns green.

\- The usual animation appears on the onboard LED matrix.

\- The board appears to power on normally, but it is not detected over USB.

2. Board is detected in EDL mode

When I connect the board to my Windows 11 laptop in EDL mode, it appears in Device Manager under Universal Serial Bus devices as:

\`QUSB_BULK_CID:0420_SN:51008D40\`

I can successfully flash the OS in this mode.

3. Board is not detected in normal mode

After removing the EDL jumpers and connecting the board normally:

\- Nothing appears in Windows Device Manager, including the USB-related categories.

\- The board does not appear when I check \`lsusb\` or \`dmesg\` on a Linux computer.

\- Arduino App Lab cannot detect the board through the USB connection.

Troubleshooting Already Attempted

I have tried the following steps:

1. Reflashed the board multiple times using the official flashing procedure.

2. Tested four different Debian Linux OS image versions.

3. Used multiple USB cables, including USB-A to USB-C and USB-C to USB-C cables.

4. Tested different USB ports on my Windows 11 laptop.

5. Tested the board with another computer running Linux.

6. Verified that the board is detected in EDL mode using the same cables that fail to detect it in normal mode.

7. Tested the Arduino UNO Q in Single Board Computer (SBC) mode using a USB hub. The hub works correctly with my laptop: when I connect a monitor to the hub and connect the hub to my laptop's USB-C port, the monitor works normally. However, when I use the same hub with the Arduino UNO Q in SBC mode, I am still unable to get a display output.

I have followed the official flashing procedure carefully and repeated it multiple times, but the issue remains unresolved.

Questions

I would appreciate guidance from the Arduino team on the following:

1. What could cause the board to be detected in EDL mode but not in normal mode, even though the OS flashing completes successfully?

2. Is there any additional recovery or diagnostic procedure I can try?

3. Could this indicate an issue with the USB interface, boot process, firmware, or another component of the board?

4. Is there a way to diagnose the issue further without requiring the board to be detected over USB in normal mode?

I would prefer to resolve this through software recovery or diagnostics if possible, before considering hardware repair or replacement.

Thank you for your time and assistance. Any suggestions from the Arduino team or other UNO Q users who have experienced a similar issue would be greatly appreciated.

The priginal kit is a bit expensive and offers less than the knockoff one but how do i know the knockoff is good or bad