I've had my MX 500 for a couple of years now and just was reading about discrete codes.I always just used the on off ones but would like to put the proper discretes in now.So from my reading I assume I need to get a cheap remote with a JP1 which can conect to a comp then get the MX 500 to learn them.I was all ready to order the 8011 kit and I got thinking of an old remote I have ,so I dug it up and it's a "A/V Producer 8"
URC-8080B02.So I take the battery holder off and there's a 6 pin thing called JP1,will this old remote do the trick I need? thanks alot

That remote should be plenty for using JP1 to create discrete codes for your MX 500.

The level of support in the JP1 group for some of the newer remotes is a little better. But that difference is more important if you want to use the JP1 remote as your final remote. It shouldn't matter for using the JP1 remote to teach another remote.