Category : Pascal Source Code
Archive   : PIBT41S2.ZIP
Filename : PIBASYNC.PAS

UNIT PibAsync;

(*----------------------------------------------------------------------*)
(* PIBASYNC.PAS --- Asynchronous I/O for Turbo Pascal *)
(*----------------------------------------------------------------------*)
(* *)
(* Author: (c) 1985, 1986, 1987 by Philip R. Burns *)
(* *)
(* Version: 1.0 (January, 1985) *)
(* 2.0 (June, 1985) *)
(* 2.1 (July, 1985) *)
(* 3.0 (October, 1985) *)
(* 3.1 (October, 1985) *)
(* 3.2 (November, 1985) *)
(* 4.0 (October, 1986) *)
(* 4.1 (December, 1986) *)
(* 4.2 (January, 1987) *)
(* 4.3 (March, 1987) *)
(* 4.4 (July, 1987) *)
(* 4.5 (November, 1987) *)
(* 4.6 (January, 1988) *)
(* 4.7 (February, 1988) *)
(* *)
(* Systems: For MSDOS/PC DOS on IBM PCs and close compatibles only. *)
(* *)
(* History: Some of these routines are based upon ones written by: *)
(* *)
(* Alan Bishop *)
(* C. J. Dunford *)
(* Michael Quinlan *)
(* Gene Harris *)
(* *)
(* I have cleaned up these other authors' code, fixed some *)
(* bugs, and added many new features. *)
(* *)
(* In particular, starting with v4.0 of PibTerm, both input *)
(* and output to the serial port is buffered and interrupt- *)
(* driven. Also, XON/XOFF support has been moved to the *)
(* serial port interrupt handler, which results in fewer *)
(* overrun problems. *)
(* *)
(* Suggestions for improvements or corrections are welcome. *)
(* *)
(* If you use this code in your own programs, please be nice *)
(* and give proper credit. *)
(* *)
(*----------------------------------------------------------------------*)
(* *)
(* Routines: *)
(* *)
(* BIOS_RS232_Init --- Use BIOS to initialize port *)
(* Async_Isr --- Com port interrupt service routine *)
(* Async_Init --- Performs initialization. *)
(* Async_Clear_Errors --- Clear pending serial port errors *)
(* Async_Reset_Port --- Resets UART parameters for port *)
(* Async_Open --- Sets up COM port *)
(* Async_Close --- Closes down COM port *)
(* Async_Carrier_Detect --- Checks for modem carrier detect *)
(* Async_Carrier_Drop --- Checks for modem carrier drop *)
(* Async_Buffer_Check --- Checks if character in COM buffer *)
(* Async_Term_Ready --- Toggles terminal ready status *)
(* Async_Find_Delay --- Find busy wait count for 1ms delay *)
(* Async_Receive --- Reads character from COM buffer *)
(* Async_Receive_With_Timeout *)
(* --- Receives char. with timeout check *)
(* Async_Ring_Detect --- If ringing detected *)
(* Async_Send --- Transmits char over COM port *)
(* Async_Send_String --- Sends string over COM port *)
(* Async_Send_String_With_Delays *)
(* --- Sends string with timed delays *)
(* Async_Send_Break --- Sends break (attention) signal *)
(* Async_Percentage_Used --- Returns percentage com buffer used *)
(* Async_Purge_Buffer --- Purges receive buffer *)
(* Async_Release_Buffers --- Free memory for serial port queues *)
(* Async_Setup_Port --- Define port base, IRQ, RS232 addr *)
(* Async_Stuff --- Insert char into receive buffer *)
(* Async_Flush_Output_Buffer *)
(* --- Flush serial port output buffer *)
(* Async_Drain_Output_Buffer *)
(* --- Wait for serial output to drain *)
(* Async_Port_Address_Given *)
(* --- Check if port address installed *)
(* Async_Send_Now --- Send character without buffering *)
(* Async_Wait_For_Quiet --- Wait for port to quiesce *)
(* *)
(*----------------------------------------------------------------------*)
(* *)
(* PIBASYNC.PAS was split into PIBASYN1.PAS and PIBASYN2.PAS at *)
(* version 3.2 of PibTerm, and into PIBASYN1, PIBASYN2, and *)
(* PIBASYN3 for v4.0 of PibTerm. The UNIT structure was added *)
(* for use with Turbo Pascal v4.0. *)
(* *)
(*----------------------------------------------------------------------*)

INTERFACE

USES
Dos, Crt, GlobType, PibTimer, PibMTask;

PROCEDURE BIOS_RS232_Init( ComPort : INTEGER; ComParm : WORD );
PROCEDURE Async_Close( Drop_DTR: BOOLEAN );
PROCEDURE Async_Clear_Errors;
PROCEDURE Async_Reset_Port( ComPort : INTEGER;
BaudRate : WORD;
Parity : CHAR;
WordSize : INTEGER;
StopBits : INTEGER );
FUNCTION Async_Open( ComPort : INTEGER;
BaudRate : WORD;
Parity : CHAR;
WordSize : INTEGER;
StopBits : INTEGER ) : BOOLEAN;
PROCEDURE Async_Send( C : Char );
FUNCTION Async_Receive( VAR C : Char ) : BOOLEAN;
PROCEDURE Async_Receive_With_Timeout( Secs : INTEGER; VAR C : INTEGER );
PROCEDURE Async_Stuff( Ch: CHAR );
PROCEDURE Async_Find_Delay( VAR One_MS_Delay : INTEGER );
PROCEDURE Async_Init( Async_Buffer_Max : INTEGER;
Async_OBuffer_Max : INTEGER;
Async_High_Lev1 : INTEGER;
Async_High_Lev2 : INTEGER;
Async_Low_Lev : INTEGER );
FUNCTION Async_Carrier_Detect : BOOLEAN;
FUNCTION Async_Carrier_Drop : BOOLEAN;
PROCEDURE Async_Term_Ready( Ready_Status : BOOLEAN );
FUNCTION Async_Buffer_Check : BOOLEAN;
FUNCTION Async_Line_Error( VAR Error_Flags: BYTE ) : BOOLEAN;
FUNCTION Async_Ring_Detect : BOOLEAN;
PROCEDURE Async_Send_Break;
PROCEDURE Async_Send_String( S : AnyStr );
PROCEDURE Async_Send_String_With_Delays( S : AnyStr;
Char_Delay : INTEGER;
EOS_Delay : INTEGER );
FUNCTION Async_Percentage_Used : REAL;
PROCEDURE Async_Purge_Buffer;
FUNCTION Async_Peek( Nchars : INTEGER ) : CHAR;
PROCEDURE Async_Setup_Port( ComPort : INTEGER;
Base_Address : INTEGER;
IRQ_Line : INTEGER;
Int_Numb : INTEGER );
PROCEDURE Async_Release_Buffers;
PROCEDURE Async_Flush_Output_Buffer;
PROCEDURE Async_Drain_Output_Buffer( Max_Wait_Time : INTEGER );
FUNCTION Async_Port_Address_Given( Com_Port : INTEGER ) : BOOLEAN;
PROCEDURE Async_Send_Now( C : Char );
FUNCTION Async_Wait_For_Quiet( Max_Wait : LONGINT;
Wait_Time: LONGINT ) : BOOLEAN;

IMPLEMENTATION
(* Ensure multitasking defined *)
{$DEFINE MTASK}

(*$I PIBASYN1.MOD *)
(*$I PIBASYN2.MOD *)
(*$I PIBASYN3.MOD *)

BEGIN (* PibAsync *)
(* Default communications parameters *)
Async_Do_CTS := FALSE;
Async_Do_DSR := FALSE;
Async_Hard_Wired_On := FALSE;
Async_Break_Length := 500;
Async_Do_XonXoff := TRUE;
Async_OV_XonXoff := TRUE;
Async_Buffer_Length := 4096;
Async_OBuffer_Length := 1132;
(* Port addresses of each com port *)

Default_Com_Base[1] := COM1_Base;
Default_Com_Base[2] := COM2_Base;
Default_Com_Base[3] := COM3_Base;
Default_Com_Base[4] := COM4_Base;

(* IRQ line for each port *)

Default_Com_Irq [1] := COM1_Irq;
Default_Com_Irq [2] := COM2_Irq;
Default_Com_Irq [3] := COM3_Irq;
Default_Com_Irq [4] := COM4_Irq;

(* Pick up address of send-a-character *)
(* routine, which is used by INLINE *)
(* code. *)

Async_Send_Addr := ADDR( Async_Send );

END (* PibAsync *).