CMDRV.401;3=CMDRV.401;2
-11,,/;DBC003/
	.IDENT	/V4.3/	;25-MAY-78
-52,52

; D.B.CURTIS MODIFIED TO ADD OPTION TO ADJUST THE NUMBER OF WORDS TRANSFERED
; IN A COP WHEN THE REQUESTED NUMBER WOULD EXTEND PAST THE END OF THE BUFFER

-127,128
;	BIT 3= CRATE OVERRUN
;	BIT 4= T02 CAMAC TIMEOUT
-236

IE.OVR=IE.SPC		;THIS ERROR OCCURES IF AN ATTEMPT IS MADE TO ACCESS
			;OUTSIDE THE DATA BUFFER
-248

WCOFOK=40	;WORDCOUNT OVERFLOW OK IS USED TO INDICATE THAT THE COP
		;SHOULD BE MODIFIED IF IT ATTEMPTS TO ACCESS PAST THE END
		;OF THE DATA BUFFER
-1072
	CLR	U.BYTR(R5)	;INITALIZE THE NUMBER OF BYTES IN THE TRNSFER
-1086,1088
	MOV	U.DBBR(R5),-(SP) ;SAVE NUMBER OF BYTES IN BUFFER
44$:	SUB	R0,U.DBBR(R5)	;SUBTRACT OFF ALLOCATED BYTES                   ;DBC4.0
	BPL	47$		;IF POS, ALL OK

	BIT	#WCOFOK,U.FLAG(R5) ;CHECK IF OVERFLOW OK
	BEQ	52$		;IF EQ NO JUST ERROR OUT

	ADD	U.DBBR(R5),R0	;ADJUST BYTE COUNT TO STOP AT END OF DATA BUF
	ASR	R0		;CONVERT TO BYTES
	BIT	#MD24,6(R2)	;CHECK IF 24 BIT MODE OPERATION AND IF IT IS,
	BEQ	45$		;
	ASR	R0		;NEED TO MODIFY WORD COUNT AGAIN
45$:	NEG	R0		;CONVERT TO NEGATIVE BEFORE SAVING IN COP
	BIC	#^C7777,R0	;CLEAN OFF CONTROLL BITS OF ADJUSTED WC
	BIC	#^C170000,4(R2)	;AND RESET WORD COUNT IN COP
	BIS	R0,4(R2)	;AND SET INTO THE COP
	MOV	(SP)+,U.DBBR(R5) ;AND RESET THE NUMBER OF FREE BYTES
	BR	40$		;AND TRY AGIAN

47$:	MOV	R0,U.BYTR(R5)	;SAVE NUMBER OF BYTES ALLOWED IN TRANSFER       ;DBC4.0
	ADD	#2,SP		;ADJUST STACK
-1096,1099
	BR	53$                                                             ;DBC4.0

52$:	ADD	#2,SP		;ADJUST STACK
50$:	MOV	#IE.OVR,R0	;SHOW ATTEMPT TO GO OUTSIDE BUFFER
53$:	SEC
/