; poll-wait for controller ready.
	jz	geter1		; loop until ready.

	mov	bx,offset errbuf	; bx = error buffer adr.
	mov	cx,nerbyts		; cx = number of error bytes.
geterl:
	in	al,data		; al = error code byte.
	mov	[bx],al		; put into buffer.
	inc	bx		; bump buffer pointer.
	loop	geterl		; dec cx, loop till zero.
	ret

	; bios stack area.
tmpsp	rw	1
	rw	40		; 20 levels.
tmp_tos	rw	0		; top of stack.

	; Teletek HD/CTC Initialization Data.
initdat	db	0		; interrupt vector.
	db	00000000b	; opti release the reset signal.
	call	fdelay			; delay at least 40 microseconds.

	; verify that controller request signal is off.
	mov	bx,0
move3:	in	al,status		; get status byte.
	test	al,request		; check request signal.
	jz	move4			; until request signal turned off.
	dec	bx
	jnz	move3			; or until waited long enough.

	; if request signal never turned off.
	mov	bx,offset msg1		; print "Load Aborted'
	call	prtmsg
	mov	bx,offset msg3		; print "HD/CTC Board Does Not Resp."
	call	prtmsg
	jmp	mwierves".
	call	prtmsg
	jmp	mwierr			; abort.

	; if no errors.
move9:	out	intrupt,al		; interrupt controller.
	mov	dmastat,0ffh		; set done status.
	clc				; clear error flag.
	ret				; return from mwreset.

	; do the operation specified by mwop.
mwrdwr:
	mov	dmastat,0		; set busy status.
	call	cmndphas		; do command phase.
	mov	al,1			; i/o direction = in.
	cmp	mwop,dmaread		; is it a read operation?
	je	mwtran			; hop if so.
	mov	al,0			; else i/o direction = out.
mwtran:	call	dataphas		; tmov	bl,0
	mov	es,bx		; put into extra segment.
	cmp	al,0		; is it a write?
	je	mwrite		; hop if so.

	; transfer 512 bytes from controller to memory.
mwread:	in	al,data		; al = a data byte.
	mov	es:[di],al	; put byte into buffer.
	inc	di		; bump buffer pointer.
	jnz	mwread2		; hop if no overflow.
	mov	bx,es		; increment segment by 64k.
	add	bx,1000h
	mov	es,bx
mwread2:
	loop	mwread		; dec cx, loop until zero.
	jmps	mwexit		; exit routine.

	; transfer 512 bytes from memory to controller.
m