ADS1115 analog gain signal module - how to run it with espruino?

I'm not sure what to suggest. This is just like setTimeout.

Maybe you want to read 4 values every second and write them to the console, you could do:

function everySecond() {
 ads.getADC(0, function(val0) {
  ads.getADC(1, function(val1) {
   ads.getADC(2, function(val2) {
    ads.getADC(3, function(val3) {
     console.log(val0,val1,val2,val3);
    });
   });
  });
 });
}

setInterval(everySecond, 1000);

Basically you call the function and it returns almost immediately. However it calls the function you supply at some point later on.