Just spotted a ROM dump of an Argentinian TK90X-A (according to this post
, the Brazilian one is a TK90X-B and has more internal differences than just the ROM), which can be downloaded here: https://www.dropbox.com/sh/vqoi6b4kaijy0id/AACIp5U8TA895f8Na0JoILYxa
Real hardware footage, here: http://www.youtube.com/watch?v=YlGKMOmk9Wg
Sources: this tweet
and this post
Things that she mentions:
-The computer is not necessarily faulty even if it shows some corrupted attributes on startup (other TK90Xs she had did similar stuff).
-That model has black keys, which makes it from 1985-1986 (later models were released with grey keys).
-This ROM displays a "Ejecutado 0:1" message instead of "OK 0:1" as in other dumped versions.
-She dumped this ROM via software using a "SAVE" command, recording the audio, converting to TZX and then trimming the data.
-The "Portuguese" ROM in the download link is a one-byte modification that she made herself. Not sure how MAME handles this kind of variations (would it just change that specific byte from the "Machine Configuration" menu instead of using a modded ROM? Also, a Brazilian version with that ROM revision might not actually exist..).
EDIT: Oh, just remembered that the Amstrad CPC may be a similar case, with the different manufacturer names.