Macro ruspiro_register::define_register

macro_rules! define_register {
    ($name:ident : ReadWrite<$t:ty> @ $addr:expr) => { ... };
    ($name:ident : ReadWrite<$t:ty> @ $addr:expr => [ $($field:ident OFFSET($offset:expr) $(BITS($bits:expr))?),* ]) => { ... };
    ($name:ident : ReadOnly<$t:ty> @ $addr:expr) => { ... };
    ($name:ident : ReadOnly<$t:ty> @ $addr:expr => [ $($field:ident OFFSET($offset:expr) $(BITS($bits:expr))?),* ]) => { ... };
    ($name:ident : WriteOnly<$t:ty> @ $addr:expr) => { ... };
    ($name:ident : WriteOnly<$t:ty> @ $addr:expr => [ $($field:ident OFFSET($offset:expr) $(BITS($bits:expr))?),* ]) => { ... };
}

Macro to define a single register with a specific defined access mode.
The access mode could one of: ReadOnly, WriteOnly, ReadWrite.
The register size/width could be one of: u8, u16, u32, u64

Examples

define_register!( GPFSEL0: ReadWrite<u32> @ 0x3F20_0000 );
 
let _ = GPFSEL0::Register.get();

const GPIO_BASE:u32 = 0x3F00_0000;
 
define_register!( GPFSEL1: ReadWrite<u32> @ GPIO_BASE + 0x04 );
 
let _ = GPFSEL1::Register.get();

To pass a more specific definition of the fields the register represents they could be added in the [] of the definition like so:

define_register!( GPFSEL2: ReadWrite<u32> @ 0x3F20_0000 => [
    FSEL20 OFFSET(0) BITS(3),
    FSEL21 OFFSET(3) BITS(3),
    FSEL22 OFFSET(6) BITS(3)
] );
 
GPFSEL2::Register.modify(GPFSEL2::FSEL21, 0b001);