;PREFIX FILE FOR DRDRV - DR-11K LOADABLE DRIVER
	.MCALL	FILIO$,IOERR$,HWDDF$,PKTDF$,DEVDF$
	FILIO$		;DEFINE I/O FUNCTION CODES
	IOERR$		;DEFINE I/O ERROR CODES
	HWDDF$		;DEFINE HARDWARE REGISTERS
	PKTDF$		;DEFINE I/O PACKET OFFSETS
	DEVDF$		;DEFINE DEVICE TABLE OFFSETS


LD$DR=1		;*** NECESSARY FOR LOADABLE DRIVERS

ATBLIM=200	;*** ABSOLUTE MAXIMUM ATB BUFFER SIZE
		;    (BUFFER SIZE SHARES ATBSTS WITH FLAG BITS....SEE BELOW)
SIZMSK=177400	;*** BITS TO MASK OFF ATB BUFFER SIZE
		;    (MUST BE COMPLEMENT OF HIGH ORDER ZEROES OF ATBLIM)

DEFMAX=16.	;DEFAULT MAXIMUM....INITIAL MAXATB VALUE IN UCB

RQSIZ=I.PRM+4	; I/O PACKET OFFSET TO TRANSFER REQUEST SIZE
INTIN=100	; DR11-K CSR INPUT INTERRUPT ENABLE BIT

NDR11S=1	;*** NUMBER OF DR11-Ks THAT THIS DRIVER HANDLES
DR0VEC=360	;INTERRUPT VECTOR OF DR0:
DR0CSR=167770	;CSR ADDRESS OF DR0:

; UCB OFFSET SYNONYMS

ATBSTS=U.CW2	; ATB STATUS WORD   (SEE BIT DEFINITIONS BELOW)
ATBPTR=U.CW3	; ATB POOL BUFFER PTR   (ATB RING BUFFER FORMAT:)
		;				-------------------
		;				DQ - DEQUEUE PTR
		;				 Q - QUEUE PTR
		;		ATBPTR->	START OF RING BUFFER
		;		Q-> DQ->	  ..........
		;				END OF RING BUFFER
		;				------------------
MAXATB=U.CW4	; MAXIMUM ATB BUFFER SIZE (in bytes), EXCLUDING PTRS (4 bytes)
		;* THIS IS ACCESSIBLE BY:  SET /BUF=DR0:128.
		;* IF MAXATB > ATBLIM, THEN ATBLIM IS THE UPPER LIMIT ANYWAY


; ATBSTS STATUS BITS
; ** LOW BYTE OF ATBSTS IS CURRENT ATB BUFFER SIZE (MINUS 4) IN BYTES
; ** (that is why ATBLIM is 255. -- some coding changes could expand this, but
; **  if 255. isn't enough, probably nothing is)

INFORK=100000	; LOCKS OUT QUEUEING OF ATB FORK ROUTINE FROM INTERRUPT LEVEL
CLRATB=40000	; FLAGS ATB FORK ROUTINE TO FLUSH ATB BUFFER
ATBOVR=20000	; FLAGS ATB BUFFER OVERFLOW


; I/O SUB-FUNCTION BITS:

DR.NTM=4	; I/O WITH NO TIMEOUT
DR.RIB=2	; DON'T PURGE INPUT BUFFER BEFORE READ
DR.ATB=1	; ENABLE INPUT BUFFER ON ATTACH