Line Follower Robot Wireless Remote

Firmware // 38 kHz IR carrier timing

void Timer2_ISR(void) interrupt 5
{
    TF2H = 0;

    if (ir_tx_enable) {
        IR_LED = !IR_LED;      // Toggle output to generate 38 kHz carrier
    } else {
        IR_LED = 0;            // Force LED off between NEC protocol bursts
    }
}

Schematic & Layout

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IR link: Generated the 38 kHz NEC carrier from a hardware timer rather than a software delay loop, so the carrier period stays inside the receiver's decode window.
Emergency stop: Put the stop on an interrupt so it runs ahead of the main control loop instead of waiting on it.
Feedback: Drove a buzzer and a vibration motor from MCU GPIO through active-low PNP stages, so the operator gets a response without looking at the remote.
Menus: Wrote the LCD menu as a state machine so each screen has one place that handles its inputs.