DEFINITION MODULE SerialIO;

	(********************************************************)
	(*							*)
	(*	     Serial I/O through the COM ports		*)
	(*							*)
	(*  Programmer:		P. Moylan			*)
	(*  Last edited:	10 March 1995			*)
	(*  Status:		Working				*)
	(*							*)
	(********************************************************)

TYPE
    SerialChannelNumber = [1..4];
    WordLength = SHORTCARD [5..8];
    Parity = (NoParity, OddParity, EvenParity, Always0, Always1);
    StopBits = SHORTCARD [1..2];

(************************************************************************)

PROCEDURE InitSerialChannel (chan: SerialChannelNumber;  baud: CARDINAL;
				wordlength: WordLength;
				parity: Parity; stopbits: StopBits);

    (* Performs initialisation on channel "chan".			*)

PROCEDURE ModemControl (chan: SerialChannelNumber;  code: BYTE);

    (* Sends the specified code to the Modem Control Register.  The	*)
    (* code bits are: bit0=DTR, bit1=RTS, bit2=Out1, bit3=Out2,		*)
    (* bit4=Loopback.  (The other 3 bits should be zero.)		*)
    (* You don't normally need to call this procedure.			*)

PROCEDURE MouseReset (chan: SerialChannelNumber);

    (* Special break sequence needed for resetting a serial mouse.	*)

PROCEDURE ReadSerial (chan: SerialChannelNumber;  VAR (*OUT*) value: BYTE);

    (* Reads one byte from a serial channel.	*)

PROCEDURE WriteSerial (chan: SerialChannelNumber;  value: BYTE);

    (* Sends one byte to an output channel.	*)

END SerialIO.