(
    ; This example shows the use of critical sections.

    ; Set short timeslice (50us) to make the effect more pronounced
    (rt-opt RT_TIMESLICE 50)

    (spawn _ unsafe 'A' 'Z')
    (spawn _ unsafe 'a' 'z')
    (spawn _ safe '0' '9') ; Notice that the sequence 0-9 is always printed in its entirety - because it is in a critical section
    (msleep 200)
    (halt)

    (proc unsafe start end
        ; This can be interrupted any time
        (:x)
        (yield)
        (ld r0 start)
        (:l)
            (ld @cout r0)
            (cmp r0 end)
            (j.eq :x)
            (inc r0)
            (j :l)
    )

    (proc safe start end
        (:again)
        (ld r0 start)
        ; The sequence will always be complete
        (crit
            (ld @cout ' ') ; space to make it easier to read
            (:l)
                (ld @cout r0)
                (cmp r0 end)
                (j.eq :x)
                (inc r0)
                (j :l)
            (:x)
            (ld @cout ' ') ; space to make it easier to read
        )
        (yield)
        (j :again)
    )
)