const cmsis = @cImport({
    @cDefine("TM4C123GH6PM", "");
    @cInclude("TM4C123GH6PM.h");
});

const GPIO_PORTF_CLK_EN: u32 = 0x20;  // Bit 5 (Port F)
const GPIO_PORTF_PIN1_EN: u32 = 0x02; // Bit 1

const LED_ON1: u32 = 0x02;

export fn _start() noreturn {
    cmsis.SYSCTL.*.RCGCGPIO |= GPIO_PORTF_CLK_EN;
    _ = cmsis.SYSCTL.*.RCGCGPIO;

    cmsis.GPIOF.*.DEN |= GPIO_PORTF_PIN1_EN;
    cmsis.GPIOF.*.DIR |= GPIO_PORTF_PIN1_EN;

    const DELAY_VALUE = 4000000;
    while (true) {
        cmsis.GPIOF.*.DATA = LED_ON1; // LED On
        Delay(DELAY_VALUE);
        cmsis.GPIOF.*.DATA = 0; // LED On
        Delay(DELAY_VALUE);
    }
}

fn Delay(delay: usize) void{
    for(0..delay) |_| {
        asm volatile ("nop");
    }
}