1pub const GpioRegister = packed struct(u8) {
 2    GPIO0: bool,
 3    GPIO1: bool,
 4    GPIO2: bool,
 5    GPIO3: bool,
 6    reserved: u4 = 0,
 7};
 8
 9const gpio: *volatile GpioRegister = @ptrFromInt(0x0123);
10
11pub fn writeToGpio(new_states: GpioRegister) void {
12    // Example of what not to do:
13    // BAD! gpio.GPIO0 = true; BAD!
14
15    // Instead, do this:
16    gpio.* = new_states;
17}
18
19// syntax