This is a classic MSX 1 computer. There were 2 versions : the PHC-28L with 64 KB RAM and the PHC-28S with only 32 KB RAM. There is also a third model labeled PHC-28P with 64 KB, but difference with PHC628L is not known yet (help welcomed). There also seemed to be a 16 KB only model...
They had small success in France. It seems that the japanese had a different colored case (cream white).
We need more info about this computer ! If you designed, used, or have more info about this system,
please send us pictures or anything you might find useful.