Today I looked into FFVII Text system. (both japanese and english).
They are the same.
There are two part of text system: kernel and field.
Kernel system allow you:
Set changable variable (only in message that appear in battle on top):
EA (used on red window), EB (Items), EC (Gil), ED (Monster), EE (Skill), EF (Monster Letter), F0 (Element (or magic)), F1 (not used).
They has 2 parameters, but I didn't see the were used... only FFFF everywhere
F8 - define text window color for battle module (second parameter not used anywhere. I think it planned to be color index but it was not compleatly implemented. In any case if F8 are in text - there will be red window, like limits)
F9 - use simple compression.
FA - extended characters.
FC - extended characters.
FD - extended characters. (not implemented in battle module, don't know why)
FE - extended characters. (not implemented in battle module, don't know why)
FF - end of text.
Next I look into Field message system.