alternate outputs every 30mins?

I have a vehicle with 2 fuel pumps plumbed in parallel that I would like to alternate every 30mins...runs pump 1 for 30 mins then switches off pump 1 and switches on pump 2 for 30mins. Looks like it would be easy to implement using a timer but it looks like they top out at 60seconds. Is there another way to make this work in the current software? thanks