procedure INIT; forward; function ISTARR:boolean ; forward; function ISTBRR:boolean; forward; function ISTAOR:boolean ; forward; function ISTBOR:boolean ; forward; function ISTAFE:boolean ; forward; function ISTBFE:boolean; forward; function ISTATR:boolean ; forward; function ISTBTR :boolean; forward; function RCVABT:CHAR ; forward; function RCVBBT:CHAR ; forward; procedure SNDABT (BT:CHAR); forward; procedure SNDBBT (BT:CHAR); forward; procedure FINIT; forward;