File DISKY328

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*20
// SUBROUTINE DISKY328.
/DRIVES DF32 & RK08 IN READ & WRITE MODES.
	 
/CALLS:  DRDE         DWRI (AS FOR TAPE)
/        QN\BN        QN\BN
	 
/WRITE ROUTINE.
	DWRI=JMP .
	LDA
	3		/SAVE BETA 3
	STC SAVE3
	SET 3
	0
	JMP SETUP	/SET DISK WORDS
	PDP
	PMODE
	6605		/DMAW
	CLA
	TAD RK8ADR
	AND C177
	6733
	JMP LEAVE
C177,	177
	 
/READ ROUTINE.
	LMODE
	DRDE=JMP .
	LDA
	3		/SAVE BETA 3
	STC SAVE3
	SET 3
	0
	JMP SETUP	/SET DISK WORDS
	PDP
	PMODE
	6603		/DMAR
	CLA
	TAD RK8ADR
	AND C177
	6735
	 
/COMMON LEAVE ROUTINE.
LEAVE,	6622		/DFSC, DF32 DUN?
	JMP .+2		/NO, CHK RK8
	JMP DUN32	/YES
	6745		/RK8 DUN?
	JMP .-4
	 
/CHECK JUST RK8 FOR ERROR. CANNOT CHECK
/BOTH & RK8 MORE PRONE TO ERROR.
	6747		/RK8 ERROR?
	JMP .+4		/NO
	JMP ERR		/YES
	 
DUN32,	6611            /DCEA, CLR DF32
	6601		/DCMA
	 
	6742		/CLR RK8
	 
/NOW LEAVE.
	LINC
	LMODE
	XSK I 3		/SET RETURN JUMP
	LDA
	3
	STC LV
	SET I 3
SAVE3,	0		/RESTORE BETA3
LLDF,	0		/RESTORE DF
LV,	0		/EXIT
	 
/REPEAT IN CASE OF DISK ERROR.
ERR,	6611		/DCEA,CLR DF32
	6601		/DCMA
	6742		/CLR RK8
	LINC
	LMODE
	JMP SETUP+3
	 
/ROUTINE TO SET UP DISK WORDS FOR DWRI OR DRDE.
SETUP,	LDA
	0
	STC SETUPX
/GET CURRENT DF, SET EA & EXIT.
	CLR
	IOB
	6214		/RDF
	STA
	LLDF
	ROR I 4		/BITS 0&1 OF CA
	STC TEM		/FOR CA, CLR AC
	ROR I 11	/LINK TO AC8, EA EXT MEM
	STA
	TEM+1		/FOR EA, EMA
	IOB
	6732		/RK8 EXT MEM
	LDA
	LLDF
	ROR 1
	BSE I
	LDF
	STC LLDF
/GET QN & SETUP CA & WA.
	LDF 5
	LDA 3
	 
	BCL I		/INSURE BN 0-177
	600
	STA 3
	STA I
RK8ADR,	0
	 
	BCL I
	4777
	ROR 1
	ADD TEM
	LDF 3
	 
	AZE		/IF=0, SET=-0
	JMP .+4
	CLR
	COM
	SKP
	 
	ADD KM1
	STA
	7751		/CUR ADR (CA) -1
	IOB
	6755
	LDA I
	7400		/-400, 2S COM
	STA
	7750		/NUM REG TO TRNSFR, WC
	IOB
	6753
	 
/SETUP EMA & DMA FROM BN.
	LDF 5
	LDA 3
	ROR 4
	BCL I
	0377
	STC TEM+2
	LDA 3
	ROL 2
	BCL I
	7077
	ADD TEM+1
	IOB
	6615		/DEAL
	LDA
	TEM+2
SETUPX,	0		/LEAVE
TEM,	0
	0
	0
/END SUBROUTINE DISKY328.



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