;AT  Modem communication program written by Doug Cox, January 1990 (using A86)
PREGETSTATUS:
  CALL CLSCRN
GETSTATUS:
  MOV DX,03FD		;LINE STATUS REGISTER
  IN AL,DX
  AND AL,1
  JZ >L1		;IF NOTHING FROM MODEM
  MOV DX,03F8           ;RECEIVE/TRANSMIT DATA REGISTER
  IN AL,DX              ;RECEIVE IT
  MOV AH,0E             ;FUNCTION TO WRITE CHAR ON SCREEN
  INT 010
  JMP SHORT GETSTATUS
L1:
  MOV AH,1              ;FUNCTION TO GET KEYBOARD STATUS
  INT 016
  JZ GETSTATUS		;IF NO KEYBOARD INPUT
  MOV AH,0		;FUNCTION TO GET KEYBOARD CHAR
  INT 016
  CMP AX,02E00		;ALT-C
  JE PREGETSTATUS
  CMP AX,02D00		;ALT-X
  JE EXIT
  CMP AL,01B            ;ESC KEY
  JE EXIT
  MOV DX,03F8		;RECEIVE/TRANSMIT DATA REGISTER
  OUT DX,AL		;SEND IT
  JMP SHORT GETSTATUS

EXIT:
CLSCRN:
  MOV AX,0700		;FUNCTION TO CLEAR SCREEN BY SCROLLING IT
  MOV BH,7		;ATTRIBUTE
  SUB CX,CX
  MOV DX,0184F
  INT 010
  MOV AH,2		;FUNCTION TO MOVE CURSOR
  SUB BX,BX
  SUB DX,DX
  INT 010
  RET