.MCALL	.MODULE
.MODULE IPEEK,VERSION=06,COMMENT=<IPEEK,IPOKE>,IDENT=NO,LIB=YES

; Copyright (c) 1998 by Mentec, Inc., Nashua, NH.
; All rights reserved
;
; This software is furnished under a license for use only on a
; single computer system and  may  be  copied  only  with  the
; inclusion of the above copyright notice.  This software,  or
; any other copies thereof, may not be provided  or  otherwise
; made available to any other person except for  use  on  such
; system and to one who agrees to these license  terms.  Title
; to  and  ownership of the software shall at all times remain
; in Mentec, Inc.
;
; The information in this document is subject to change without
; notice and should not be construed as a commitment by Digital
; Equipment Corporation, or Mentec, Inc.
;
; Digital and Mentec  assume  no  responsibility for the use or
; reliability of its software on equipment which is not supplied
; by Digital  or Mentec,  and listed  in the  Software  Product
; Description.
	.SBTTL	Post Release Edit History

;+
;
; (05/01) 20-Oct-93 Megan Gentry
;		Fixed bug in IPEEK which returned the address rather
;		than the contents of the specified address.
; 06	13-Jan-1998	TDS	Bump version to 06 for 5.7 release
;-

	.SBTTL	Module Declarations

	.NLIST
	.ENABL	LC
	.DSABL	GBL
	.NLIST	CND
	.LIST
; ++
; FACILITY:
;
;    RT-11 System Subroutine Library
;
; CALLABLE ENTRIES:
;
;	IPEEK, IPOKE
;
; ENVIRONMENT:
;
;    These routines can be used by any job running in a single-job
;    or multi-job environment.  It uses "TRAP" to provide  error
;    processing.
;
; INCLUDE FILES:
;

	; SYSMAC.SML		; RT-11 system macro library.

;
; EXTERNAL REFERENCES:
;

	.GLOBL	$NXVAL		; Entry point to next address routine.
	.GLOBL	$SYSLB		; Include system library work area.
	.WEAK	$MSARG		; Trap code for missing argument
	.SBTTL	IPEEK - Fortran-callable Routine

; ++
; FUNCTIONAL DESCRIPTION:
;
;    The IPEEK function returns the  contents  of  a  word  located  at a
;    specified 16-bit address in the current job's address space.
;
; CALLING SEQUENCE:
;
;    i = IPEEK( iaddr )
;
; INPUT PARAMETERS:
;
;    R5	     -	address of IPEEK's argument block
;
;    0(R5)   -	argument count of IPEEK call
;    2(R5)   -	address of word to return contents of
;
; RETURNED FUNCTION VALUE:
;
;	i   -    contents of word specified by passed address
;
; --
	.SBTTL	IPOKE - Fortran-callable subroutine

; ++
; FUNCTIONAL DESCRIPTION:
;
;    The IPOKE routine  stores a passed 16-bit  value into a word located
;    at a specified 16-bit address in the current job's address space.
;
; CALLING SEQUENCE:
;
;    CALL IPOKE( iaddr, ivalue )
;
; INPUT PARAMETERS:
;
;    R5	     -	address of IPOKE's argument block
;
;    0(R5)   -	argument count of IPOKE call
;    2(R5)   -	address of word to modify
;    4(R5)   -	address of value to store in word specified by 'iaddr'
; --

	.SBTTL	IPEEK - Fortran-callable subroutine

	.PSECT	SYS$I

IPEEK::	MOV	(R5)+,R4	; R4(low byte) <-- argument count
	CALL	$NXVAL		; get 'iaddr'
	BCS	ERR		; It wasn't supplied...
	MOV	@R0,R0		; Get contents of specified address
	RETURN

POKE::
IPOKE::
	MOV	(R5)+,R4	; R4(low byte) <- argument count.

	CALL	$NXVAL		; Get -> 'iaddr' argument;
	BCS	ERR		; If CS, error - 'iaddr' wasn't  supplied
	MOV	R0,R3		; R3 <- address of word to modify.

	CALL	$NXVAL		; Get 'ivalue' argument
	BCS	ERR		; If CS, error - 'ivalue' wasn't  supplied;
	MOV	R0,@R3		; Store value in specified word.
	RETURN			; Return to caller.

ERR:	TRAP	$MSARG		; Handle any missing arguments in call;
	RETURN

	.END