The FM 77 AV was an impressive system in 1985. It's a good example of what was developped in Japan and we never heard of in the rest of the world.
The system has great audio and video features, hence the AV for "Audio and Video". It can display 640 x 200 pixels in two colors, or 320 x 200 in 4096 colors ! There is even a multipage mode where you can define two 460 x 200 screens with 8 colors each, or six 640 x 200 monochrome screens !
There are a lot of graphical symbols already stored in memory (each symbol / letter is composed by 8 x 8 pixels) : 69 alphanumeric symbols, 63 kakatana signs, 63 hiragana signs and 62 graphic symbols. Moreover, the system is capable of displaying 3418 chinese and asiatic characters with a 16 x 16 character matrix (text resolution is thus of 40 x 12).
Last but not least, the FM 77 AV offers superimposition features...
On the sound side, it offers three FM voices and three more PSG voices. Other cool features include infra-red keyboard and built-in real time clock.
There were two models : the AV-1 which has one 3.5" disk-drive (double density) built-in and the AV-2 which is equiped with two of these drives.