Your coin said:
IMPCAFSTAEUTADRAN TONINVSAYGPIUS" (80%)
Best guess might be:
IMP CAES T AEL TRIB ANTONINVS AVG PIVS
From the link below:
A typical legend on a Antoninus Pius:
IMP T AEL CAES HADR ANTONINVS
AVG PIVS PM TRP COS DES II
IMP - IMPERATOR: The title that English adopted to mean 'Emperor' meant 'leader of the army' to the Romans. The award was generally taken on becoming Emperor and renewed whenever a particularly important victory was celebrated. In some cases, these subsequent awards, denoted by a numeral following IMP, allow dating of coins to a very short period. Other Emperors made little use of the title and only assumed the initial award. Our example of Domitian shows IMP XXII; each of the other coins uses the initial IMP without numeral.
CAES, CAE, C - CAESAR: The family name of the first Emperors recalled their being related to Julius Caesar. Even after there was no 'blood' relationship, the term was applied to the Imperial family. When used alone or with an abbreviation for 'Noble' (NC, NOB C, NOB CAES etc), Caesar denoted a junior person, usually a son or the heir apparent.
AVG - AVGVSTVS: Augustus was the title that actually meant 'Emperor'. The first Emperor made the title ('Revered') almost a personal name and it was assumed on ascension by each successive ruler. Until the late Empire, Emperors were both Caesar and Augustus but toward the end the title Caesar was dropped or reserved for the junior members of the imperial family. When there were two emperors, the plural is sometimes shown as AVGG. More rarely (see Numerian below) AVGGG indicated there were three rulers.
TRP, TRIB POT, P - TRIBVNICIA POTESTAS: An important Republican office was Tribune of the People (plebs) with the power to veto acts of the Senate. The office was first taken on ascension and renewed annually. At first the renewals dated to 10 December (the traditional date) but some rulers used the anniversary of their ascension or 1 January so it is necessary to know which system was in use before dating each reign. Many coins are seen dated with a split year (e.g. 11/12 AD) which means the TRP numeral placed the coin from 10 Dec 11 to 9 Dec 12. From the time of Septimius Severus, 1 January was used regularly. When TRP with numeral is used, it is the best dating device found on Roman coins. TRP with no numeral was the form for the first year; TRP I was not used. Occasionally TRP was used without a numeral even though the coin was struck after the first regnal year. Note the as of Tiberius used to illustrate SC used a long form spelling of TRP. As time went on the shorter abbreviations became standard.