[рони]

yaparoff,
window.timerId = window.setInterval(tick(time), 1000);

window.timerId = window.setInterval(function() {
 time = tick(time)
}, 1000);

function tick(timerTime) {
    timerTime = timerTime - 1;
        //???
    showTime(timerTime);
    return timerTime;
}