Nintendo GAME BOY Programming Manual page 248

Game Boy Programming Manual
Game Boy
Printer status normal
↓
Start communication
↓
Cable disconnects during data transfer
↓
Printer status = FFh
↓
Confirm reset of printer connection
↓
Check connection after 100 msec
Printer
Printer normal
↓
Wait to receive data
↓
Data reception
↓
Preamble detection failure
↓
Set status to FFh
↓
80 msec delay
↓
Printer initialization
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