*20
/DISK HANDLER
/CALL
/READ=3, WRITE=5
/XCORE
/CORE
/XDISK
/DISK
/-N. WORDS 2S COMP
/
DODSK,	FETCH		/3 READ, 5 WRITE
	BSE I
	6600
	STC D32COM	/DMAR, DMAW
	ADD D32COM
	ROL 11
	BCL I
	3777
	STC RK8COM	/DLAG
	 
	FETCH		/X CORE
	BCL I
	7770
	ROL 3
	STA I
CEXT,	0		/EX MEM BITS
	 
	FETCH		/CORE ADR
	STA I
CORLOC,	0
	PDP
	PMODE
	CLA CMA		/AC=-1
	TAD CORLOC
	LINC
	LMODE
	LDF 3
	STA
	3751		/WC
	 
	FETCH		/X DISK
	ADD RK8COM
	STC RK8COM
	 
	FETCH		/DISK ADR
	STC DADR
	CLR
	ADD DADR
	BCL I
	7000
	SCR 4
	ROL 6
	ADD CEXT
	STC DDEAL
	QAC
	ROL 1
	STC D32ADR
	 
	FETCH		/-WC, 2S COMP
	LDF 3
	STA
	3750		/WC
	SCR 10		/DIV BY 256
	STC DBLKS
	 
/CHECK TO SEE WHICH DISK IS UP. DF32 IS
/DEFAULT.
	PDP
	PMODE
	CLA CMA		/AC=7777
	DRST		/8E STATUS
	RTL		/BIT 2 TO 0
	 JMP DF32	/NO 8E, ASSUME 32
	 
/8E EXISTS, BUT IS IT ON.
	RTL		/BIT 4 TO 0
	SMA
	 JMP RK8E	/8E IS ON
	 
/DF32 RUNNER.
DF32,	CLA
	TAD DDEAL
	DEAL
	CLA
	TAD D32ADR
D32COM,	0		/DMAR OR DMAW
	DFSC		/DUN?
	 JMP .-1
	DFSE		/ERRORS?
	 JMP DF32	/YES, RETRY
	 
/OK, LEAVE.
LVDSK,	DCEA
	DCMA
	LINC
	LMODE
	JMP GOUSER
	 
	PMODE
/RK8E RUNNER.
RK8E,	DCLR		/CLEAR STATUS
	DRST		/WAIT TIL CLR
	SZA CLA
	 JMP .-2
	 
	TAD CORLOC
	DLCA
NXTBLK,	TAD CEXT
	TAD RK8COM
	DLDC		/COM GER
	TAD DADR
	DLAG		/LOAD DSKADR & GO
	DSKP		/DUN?
	 JMP .-1
	DRST		/STATUS TO AC
	CLL RAL		/CLR SUCCESS BIT
	SNA
	 JMP MR8E	/OK, NEXT BLK
	 
/8E ERROR ROUTINE. FIRST CHECK FOR SEEK 
/FAILED OR CYLINDER ADDRESS ERROR. RECAL
/FOR THESE.
BAD8E,	AND K1002	/NOTE AC RAL
	SNA CLA
	 JMP RK8E	/OTHER, RETRY
/RECAL & RETRY.
	DCLR		/CLR STATUS
	STL RTL		/AC=2
	DCLR		/RECAL
	DSKP		/WAIT DUN
	 JMP .-1
	JMP RK8E	/RETRY
	 
/ROUTINE TO SUBSEQUENT 8E BLKS.
MR8E,	ISZ DADR	/BUMP DISK ADDR
	ISZ DBLKS	/? DUN
	SKP
	JMP LVDSK	/LEAVE, DUN
	TAD K1000	/MAKE WRITE ALL
	JMP NXTBLK
	 
/CONSTANTS & STOREAGE LOCATIONS.
DADR,	0
DBLKS,	0
K1000,	1000
K1002,	1002
DDEAL,	0
D32ADR,	0
RK8COM,	0
	 
	LMODE