Macro boot 

macro_rules! boot {
    ($peripherals:ident, $rng:ident, $entropy_source:ident, $sw_int1:ident) => { ... };
}

The ssh-stamp boot sequence, which does heap allocation, esp_hal::init, configures the entropy source, flash storage and the esp-rtos scheduler.

The Peripherals struct cannot be returned once fields have been moved out of it, so the caller names the bindings and the macro introduces them into scope, e.g:

ssh_stamp_esp32::boot!(peripherals, rng, entropy_source, sw_int1);