This MSX system has only 8 KB and one cartridge slot, the minimum required by the MSX standard. It is the first MSX computer conceived by Casio and was marketed as an initiation machine.
Thankfully an expansion unit (KB-7) was available and added two cartridge slots and more memory (8 + 8 = 16 KB) to the PV-7.
There was a small drawing program in ROM. The chicklet keyboard is very poor and to small to do anything with it. There are big arrow keys on the right hand side of the keyboard arranged in circle. The whole pad is called "Joypad 1" and emulates a joystick inserted in port #1. The two big blue keys "TR1" and "TR2" on the left hand side of the keyboard are the two fire buttons! Notice that there are also "classic" arrow keys at the top of the keyboard...
The PV-7 was followed by the PV-16 which had 16 KB RAM, as the 8 KB of the PV-7 were not enough to run most of the MSX software.
We need more info about this pong ! If you designed, used, or have more info about this system,
please send us pictures or anything you might find useful.