This page has been deprecated. The most up-to-date version of AmberTools is 13, and it is fully compatible with Amber 12. If you have AmberTools 12, you can upgrade in-place to AmberTools 13 using the command:
cd $AMBERHOME ./update_amber --upgrade
If you get a message that complains about a message like:
bash: ./update_amber: No such file or directory
then make sure you run
until it reports that AmberTools 12 is fully up-to-date.
Once you have AmberTools 13, please see Installing Amber12 and AmberTools 13 for instructions.