A catalog client Script that is triggered on second keydown, is this possible?

[Lon Landry4]

Basically, I am trying to move the cursor to next field; once first field is populated.

Then, I want to move to third field when second field populated, and so on.

I can achieve this with an onLoad script for the first field but not subsequent fields.

The first script works fine for detecting the first keydown.

But, second script below does not.

Can keydown be used in an onChange Client script?
(or does the system wait until user clicks out of the field)

Can a second keydown be detected?
(then I could use an onLoad script...)

Any ideas out there?

Thanks for your time,
Lon

Example #1 

function onLoad() {

 //Get control of field to identify keyup event, then pause for 1/10 of a second  

    var control = g_form.getControl('first_asset_tag');

control.onkeyup = nextField;

window.setTimeout(nextField,100); 

//Move cursor to next field

function nextField(){ 

g_form.getControl('first_serial_number').focus();

}

} 

Example 2

function onChange(control, oldValue, newValue, isLoading) {

   if (isLoading || newValue == '') {

      return;

   }

//Get control of field to identify keyup event, then pause for 1/10 of a second  

    var control1 = g_form.getControl('first_serial_number');

control1.onkeyup = nextField1;

window.setTimeout(nextField1,100); 

function nextField1(){

//Move cursor to next field

g_form.getControl('first_mac_address').focus();

}

}