DEFINITION MODULE rs;
TYPE pt = (None,Even,Odd,Mark,Space);
     wl = SHORTCARD[5..8];

PROCEDURE Init( Baud       : CARDINAL;
                WordLength : wl;
                Parity     : pt;
                OneStopBit : BOOLEAN;
                HandShake  : BOOLEAN);

PROCEDURE RxCount():CARDINAL;
(* Return Number of recived bytes in buffer *)

PROCEDURE TxCount():CARDINAL;
(* Return Number bytes still to be send *)

PROCEDURE TxFree ():CARDINAL;
(* Return Number of bytes free in buffer *)

PROCEDURE Break  (   Time : CARDINAL );
(* Send a break for the duration on Time milliseconds *)

PROCEDURE BreakTest():BOOLEAN;
(* Test for break *)

PROCEDURE Receive(VAR Buf : ARRAY OF BYTE; Len : CARDINAL );
(* Read from input buffer *)

PROCEDURE Send   (    Buf : ARRAY OF BYTE; Len : CARDINAL );
(* Write to Output Buffer *)

PROCEDURE Install( Port : CARDINAL);
(* Install Interrupt handler.                             *)
(* Must be done before any access to the above procedures *)

PROCEDURE Install2( Port,Intr : CARDINAL);
(* Alternative to Install, allowing interrupt to be specified *)

END rs.