// FIXME add attributes to allocate these at fixed addresses
uint32_t target = 0;
uint32_t current = 0;
bool halt_requested = false;

// PUL/DIR version (ENA optional)
int main()
{
    set PUL and ENA high;
    wait 300 ms;
    while( ! halt_requested ) {
        int32_t delta = target - current;
        if( delta == 0 )
            continue;
        if( delta < 0 ) {
            --current;
            if( DIR is low ) {
                set DIR high;
                wait 2 us;
            }
        } else {
            ++current;
            if( DIR is high ) {
                set DIR low;
                wait 2 us;
            }
        }
        set PUL low;
        wait 1 us;
        set PUL high;
        wait 1 us;
    }
    set ENA low;
    __halt();
}

// CW/CCW version (ENA optional)
int main()
{
    set CW, CCW and ENA high;
    wait 300 ms;
    while( ! halt_requested ) {
        int32_t delta = target - current;
        if( delta == 0 )
            continue;
        if( delta < 0 ) {
            --current;
            set CCW low;
        } else {
            ++current;
            set CW low;
        }
        wait 1 us;
        set CW and CCW high;
        wait 1 us;
    }
    set ENA low;
    __halt();
}