The two patches here adds a full-fledged ATB meter and a system where one can skip turns by pressing the X Button. This patch is meant for an unheadered and unpatched Revision 1 ROM of the Japanese version of FF4. It does not work on FF2us, Easy Type, or the J2e translation.
Source code for the ATB bar patch: http://x11.s11.xrea.com/dist/ff4/ff4_atb.asm
Source code for the skip turns patch: http://x11.s11.xrea.com/dist/ff4/ff4_atb_switch.asm
Database match: Final Fantasy IV (Japan) (Rev 1)
Database: No-Intro: Super Nintendo Entertainment System (v. 20210222-050638)
File/ROM SHA-1: EAC14578B3465FFCE874119005F9B244E8565A79
File/ROM CRC32: CAA15E97