Judging by https://github.com/gbdev/pandocs/blob/master/src/Power_Up_Sequence.md and a cursory search of other files, the cgbE and stadium 2 boot ROMs do not appear to be documented in this reference sheet.
Judging by https://github.com/gbdev/pandocs/blob/master/src/Power_Up_Sequence.md and a cursory search of other files, the cgbE and stadium 2 boot ROMs do not appear to be documented in this reference sheet.