Any way to specify grid size with splitter?

I’m going to be integrating data from some other sources with split OSM data and it would be convenient to have the splitter tile my area of interest into 30 minute or 15 minute grids. I assume there’s a way to tweak the areas.list file to cause this to happen, but I don’t know how to convert from degrees to the units the splitter uses.

Ask, and ye shall receive:
http://www.cferrero.net/maps/downloads/lat-long_to_garmin_converter.xls

Enter the lat and long in the yellow boxes, the green boxes will contain the appropriate Garmin coordinates.

There’s a bit more explanation of the areas.list and Garmin coordinates here: http://www.cferrero.net/maps/splitter_advanced.html

Thanks, csdf. This looks like just what I needed.