OBJNAM WAIT.SBR ; Last modified 30-Dec-85
; Subroutine to WAIT for specified number of seconds (can use fractions)
; by Irv Bromberg, Medic/OS Consultants, Toronto, CANADA
RADIX 10
VEDIT=11
VMINOR=1
VMAJOR=5
VSUB=0

IF EQ,1

Calling syntax: XCALL WAIT {,Delay}

where Delay is a floating point or string parameter containing a decimal
delay value in seconds (fractional parts may be used). This version of
WAIT.SBR waits for OIP to finish before starting the delay. If Delay=0
or no parameters are passed subroutine simply returns after waiting for
OIP to clear. If the operator hits ^C the sleeping is aborted at the end
of the current 100th of a second.

Advantages over Alpha Micro's SLEEP.SBR:

Control-C can abort the sleep period. Waits for output-in-progress to
the user's terminal to finish before starting the sleep.  Does the OIP
wait even if no parameters are passed or the delay=0, can be used to
make sure output has flushed before continuing (for example if next step
will modify user's terminal status word).  Changes JOBPRG(JCB) to [WAIT]
when the system is in "test" mode (using SET TEST command) while
waiting, so SYSTAT or STAT can display what the job is doing (restores
JOBPRG after delay complete).

ENDC

SEARCH SYS
SEARCH SYSSYM
SEARCH TRM

Impure=A0
JCB=A1
Value=A2
ArgBas=A3
Worksp=A4
TCB=A5
Atemp=A6
Source=A6

Ticks=D1

; SY$TST=256	; remove semi-colon before this equate if assembling on
		; system with AMOS/L version prior to 1.3

SCALE=128	; offset to SCALE factor in BASIC Impure Workspace

	PHDR	-1,0,PH$REE!PH$REU 

	MOV	JOBCUR,JCB		; index user's Job Control Block
	MOV	JOBTRM(JCB),TCB		; index user's Terminal Control Block
	PUSH	JOBPRG(JCB)		; save current JOBPRG
	MOV	SYSTEM,D7		; is system in "test" mode?
	AND	#SY$TST,D7		; if so then change JOBPRG=[WAIT]
	BEQ	WaitOIP			; note this has no effect under AMOS/L
	MOV	#<[WAI]_16+[T  ]>,JOBPRG(JCB) ; versions prior to 1.3 unless
					; the user has a program to set SY$TST

WaitOIP:TSTB	T.STS(TCB)		; wait for OIP to clear before delay
	BPL	GetVal
	SLEEP	#500			; 50ms wait each time around loop
	BR	WaitOIP

GetVal:	TSTW	@ArgBas			; wait only for OIP to clear if no
	BEQ	Done			; parameter is passed
	TST	8(ArgBas)		; check parameter size
	BEQ	Done			; NULL parameter, wait only for OIP
	CMPW	2(ArgBas),#4		; is it floating parameter?
	BNE	Done			; no, wait only for OIP

GetFlt:	SUB	#6,SP			; get some workspace
	MOV	SP,Worksp
	MOV	4(ArgBas),Source	; get desired seconds to sleep
	MOVB	(Source)+,(Worksp)+
	MOVB	(Source)+,(Worksp)+
	MOVB	(Source)+,(Worksp)+
	MOVB	(Source)+,(Worksp)+
	MOVB	(Source)+,(Worksp)+
	MOVB	(Source)+,(Worksp)+
	MOV	SP,Worksp		; restore pointer
	MOV	Scale(Impure),D7	; scale factor in use?
	NEG	D7			; if so we have to unscale the value
	ADD	#2,D7			; but multiply to 100ths of second
	BEQ	10$			; could be zero if SCALE 2 if effect
	FPWR	@Worksp,D7
10$:	FFTOL	@Worksp,Ticks		; convert to longword
	ADD	#6,SP			; return the workspace
	TST	Ticks
	BEQ	Done			; quit if 0 delay requested
Loop:	SLEEP	#96			; sleep 1/100s (-4 for overhead)
	TSTB	JOBSTS(JCB)		; ^C pending?
	BMI	Done			; yes, abort
	DEC	Ticks			; countdown
	BNE	Loop			; more if not zero yet

Done:	POP	JOBPRG(JCB)
	RTN

	END

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