Coupon: have different discount for some products in discounted category

I have a coupon that gives some customers 20% discount on a specific category. But some specific products must not give 20% but 10% discount. These products resides all in the same category.
I have tried to do this with different coupons under a parent coupon, but cannot get it to work. Is it possible to accomplish this?

Hello,

Ok, from what I understand you set up a category to receive 20% discount entering a specific coupon code. What you waht you want is to exclude some of thhe products in that category and give them a 10% discount instead?

Cant really be done in the current setup. What I would suggest is to create 2 categories, a 20-discount and a 10-discount and add the products to the appropriate category. Then you can use a parent coupon to combine the coupon discounts into 1 coupon code.