PingPong is an early boot sector virus from March 1988.
PingPong is introduced to a system when it is booted from an infected floppy disk. When the disk is booted, the virus becomes memory resident. The original boot sector is moved to a free location on the disk, which is marked as a bad sector. While the virus is resident, it will infect any floppy disk accessed for reading or writing.
30 minutes after the virus activates, it displays a ball (a period) that bounces off the edges of the screen or off of certain characters. This virus does nothing destructive except to annoy the user with the ball.
The variant known as Typo is similar to the original in most respects, except that it causes errors in any document going out to the printer.
Pingpong was the most common boot sector virus until Stoned.
The virus had the same problem with the POP CS instruction as Alameda, it could only infect on 8080 and 8086 machines.
Totally Geek, PingPong Assembly Code.
F-Secure Antivirus, F-Secure Virus Descriptions : Ping-Pong.
Joe Wells. IBM Research, Timeline. 1996.08.30