Revert "Revert 9e69504..05d7d89"

This reverts commit f94d64e9c60bc6621c099537d921a77d53abcf1c.
Revert "Update esp"

This reverts commit 05d7d898739ff039d01d4985c3dc01e772fb418d.
Revert "Merge pull request #1 from spymodem/master"

This reverts commit 0d073d439e8b6d973cfa6ac3272dfbfedec108b6, reversing
changes made to 9e69504f762c8eb150dfa9d8ee9ebd907309c5ca.