XML Number counter

Hi Guys

I have the following XML file which is feeding data into another software that I am using:

<?xml version='1.0' encoding='ISO-8859-1' ?><till_id>1</till_id><order_id>3</order_id>

The software is using the <till_id> and <order_id> strings.

However I need something on the other end.
Is there a simple Batch file, or an html button that I can create that simply does the following:
If I run file number 1, it will show till_id 1, and increase the order_id by 1
if I run file number 2, it will show till_id 2, and increase the order_id by 2
etc for 6 tills.

Any ideas?
I thought of running a BAT file, but I prefer some HTML scripting as that might work quicker.

thanks!