Updates and new folder structure

2026-02-04 21:28:47 +10:00
parent 8495cf296a
commit 78c5c9ae82
12 changed files with 5 additions and 5 deletions
@@ -0,0 +1,156 @@
+;This is a disk boot routine for the 1771/1791 type disk
+;controllers.  It would normally reside on track 0,
+;sector 1, to be loaded by the "B" command of the
+;monitor at address 200H.  By changing the equates
+;below, it may be configured to load any size of
+;program at any address.  The program is assumed to
+;occupy consecutive sectors starting at track 0, sector
+;2, and will begin exection at its load address (which
+;must be a 16-byte boundary) with the Instruction
+;Pointer set to zero.
+
+; Variations are available for the Cromemco 4FDC with
+; large disks, the 4FDC with small disks, the Tarbell
+; single-density controller, and the Tarbell double-
+; density controller. Select one.
+
+CROMEMCOSMALL:	EQU	0
+CROMEMCOLARGE:	EQU	1
+TARBELLSINGLE:	EQU	0
+TARBELLDOUBLE:	EQU	0
+
+LOAD:	EQU	400H	;Address to load program
+SEG:	EQU	40H	;LOAD/10H
+SECTOR:	EQU	51	;No. of 128-byte sectors to load
+BOOTER:	EQU	200H	;"B" command puts booter here
+
+;**************************************************************
+
+CROMEMCO:	EQU	CROMEMCOLARGE+CROMEMCOSMALL
+TARBELL:	EQU	TARBELLSINGLE+TARBELLDOUBLE
+
+WD1771:	EQU	CROMEMCO+TARBELLSINGLE
+WD1791:	EQU	TARBELLDOUBLE
+
+SMALL:	EQU	CROMEMCOSMALL
+LARGE:	EQU	CROMEMCOLARGE+TARBELL
+
+	IF	SMALL
+MAXSECT:EQU	18
+	ENDIF
+
+	IF	LARGE
+MAXSECT:EQU	26
+	ENDIF
+
+	IF	TARBELL
+DISK:	EQU	78H
+	ENDIF
+
+	IF	CROMEMCO
+DISK:	EQU	30H
+	ENDIF
+
+	IF	WD1771
+READCOM:EQU	88H
+	ENDIF
+
+	IF	WD1791
+READCOM:EQU	80H
+	ENDIF
+
+	IF	CROMEMCOLARGE
+WAITBYTE:EQU	0B1H
+	ENDIF
+
+	IF	CROMEMCOSMALL
+WAITBYTE:EQU	0A1H
+	ENDIF
+
+	ORG	BOOTER
+	PUT	100H
+
+	XOR	AX,AX
+	MOV	DS,AX
+	MOV	ES,AX
+	MOV	SS,AX
+	UP
+	MOV	DI,LOAD
+	MOV	DX,SECTOR
+	MOV	BL,2
+SECT:
+	MOV	AL,BL
+	OUTB	DISK+2
+	MOV	CX,128
+
+	IF	TARBELL
+	INB	DISK		;Get head load status
+	ENDIF
+
+	IF	CROMEMCO
+	INB	DISK+4		;Get head load status
+	ENDIF
+
+	TEST	AL,20H
+	MOV	AL,READCOM
+	JNZ	OUTCOM
+	MOV	AL,READCOM+4
+OUTCOM:
+	OUTB	DISK
+
+	IF	CROMEMCO
+	MOV	AL,WAITBYTE
+	OUT	DISK+4		;Turn on hardware wait
+	ENDIF
+
+READ:
+	INB	DISK+4
+
+	IF	TARBELL
+	ROL	AL
+	JNC	DONE
+	ENDIF
+
+	IF	CROMEMCO
+	ROR	AL
+	JC	DONE
+	ENDIF
+
+	INB	DISK+3
+	STOB
+	LOOP	READ
+GETSTAT:
+	INB	DISK+4
+
+	IF	TARBELL
+	ROL	AL
+	JC	GETSTAT
+	ENDIF
+
+	IF	CROMEMCO
+	ROR	AL
+	JNC	GETSTAT
+	ENDIF
+
+DONE:
+	IN	DISK
+	AND	AL,9CH
+	JNZ	SECT
+	DEC	DX
+	JZ	BOOT
+	INC	BL
+	CMP	BL,MAXSECT+1
+	JNZ	SECT
+	XOR	BL,BL
+	INC	DX
+	MOV	AL,58H		;Step in with update
+	OUTB	DISK
+	JP	GETSTAT
+
+BOOT:
+	MOV	AX,SEG
+	MOV	SS,AX
+	MOV	ES,AX
+	MOV	DS,AX
+	JMP	0,SEG
+