I have a table within a form using a repetition of the below code so that there are 5 columns each with 20 rows named 1-20 down the first column 21-40 down the 2nd column etc.  The user needs to enter choices 1-100 in the cells.  How do I make the TAB or soft enter key take the user to the NEXT cell down rather than the next cell across? I want the user to enter data in cell 1 then hit tab or soft enter and go to cell 2 etc, down the first column then up to the first cell in the second column etc.  

Also, does anyone have any advice on how to make a cell entry required?  I have a submit button at the bottom of the form and would like to display an error message to the user if certain fields are not filled in.

Thanks for any help you can give me.  I am an HTML novice, obviously.



  
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CHECK out >this reference< and bookmark it.  You'll probably USE it a lot.  The attribute you're looking for is "tabindex".