OBJNAM BASE.FXO ; Created 22-Nov-84, Last modified 3-Mar-85
; by Irv Bromberg, Medic/OS Consultants
; 78 Wildginger Way, Toronto, Ontario, CANADA   M3H 5X1
VEDIT=15.
VMINOR=2
VMAJOR=4
VSUB=0

IF EQ,1

AlphaFIX overlay equivalent to monitor-level BASE.LIT command

Syntax: BASE O  for octal
        BASE D  for decimal
	BASE H  for hexadecimal

When base is changed V-bit will be set to cause AlphaFIX to redisplay screen.

For decimal mode to work the OCVT patch must have been activated during
system bootup by placing the OCTPCH command near the beginning of the
AMOSL.INI file (prior to any SYSTEM commands).

ENDC

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

Impure	=A0
JCB	=A1
Buffer	=A2
Mode	=D0
Number	=D1
CrtCmd	=D1

Base	=1240	; offset in IMPURE.FIX where current number base stored
J.DEC=^O10000
Cmd=^H0FF00

	MOVW	#Cmd!9.,CrtCmd		; clear to end of line
	TCRT

	MOV	JOBCUR,JCB		; save existing OCT/DEC/HEX mode bits
	MOVW	JOBTYP(JCB),Mode	; get current mode
	BYP
	TRM
	BEQ	Syntax
	CMPB	@Buffer,#'O
	BNE	TryDec
	ANDW	#^C<J.DEC!J.HEX>,JOBTYP(JCB)
	MOVB	#8.,Base(Impure)
	JMP	Done
TryDec:	CMPB	@Buffer,#'D
	BNE	TryHex
	; check if OCVT patch active, error if it has not been installed
	PUSHW	JOBTYP(JCB)
	ORW	#<J.DEC!J.HEX>,JOBTYP(JCB) ; set DEC mode
	PUSHW				; get some workspace
	MOV	SP,Buffer
	MOV	#11.,Number		; output the number 11 - if DEC patch
	OCVT	0,OT$MEM		; not active result will be "B"
	POPW	Number
	POPW	JOBTYP(JCB)		; restore original OCT/DEC/HEX mode
	CMPW	Number,#<'1_8.+'1>	; did we get "11" ?
	BEQ	OK			; yes, all OK
	TYPECR	<?OCVT patch has not been installed>
	LCC	#PS.Z			; do not redisplay screen
	RTN
OK:	MOVB	#10.,Base(Impure)
	ORW	#<J.HEX!J.DEC>,JOBTYP(JCB)
	BR	Done
TryHex:	CMPB	@Buffer,#'H
	BEQ	SetHex
Syntax:	TYPESP	<?Illegal BASE code:  O=Octal  D=Decimal  H=Hexadecimal>
	RTN
SetHex:	ANDW	#^C<J.DEC>,JOBTYP(JCB)
	ORW	#J.HEX,JOBTYP(JCB)
	MOVB	#16.,Base(Impure)
Done:	CMPW	Mode,JOBTYP(JCB)	; has base been changed?
	BNE	ReDisp			; yes, redisplay screen
	TYPE	<BASE unchanged>
	LCC	#PS.Z	; do not redisplay screen
	RTN
ReDisp:	LCC	#PS.V	; yes, return V-bit set so screen redisplayed
	RTN
	END

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