status.
	test	al,error	; look at error bits.
	mov	al,0
	jz	stat2		; hop if no errors.

	call	geterr		; get error bytes from controller.
	mov	al,errbuf	; al = first byte.
	test	al,1		; if fatal errors.
	mov	al,1		;	then set error flag.
	jnz	stat1		;	else
	xor	al,al		;		reset error flag.
stat1:
stat2:
	out	intrupt,al	; interrupt the controller.
	ret

	; geterr - get error code bits.

geterr:
	out	intrupt,al	; interrupt the controller.

geter1:	in	al,status	; al = status.
	test	al,ready	 cmd buffer.

rwsect:	mov	al,rtcnt		;get number of retries.
	mov	byte ptr ercnt,al
retry:	call	mwrdwr			; read or write a sector.
	mov	al,0
	jc	l_3			; hop if error.
	ret				;back to mp/m.
l_3:
	dec	ercnt			; decrement error count.
	jnz	retry
	stc				; set error flag.
	ret
;
; reset the controller and setup the default parameters.
;
mwreset:
	mov	dmastat,0		; set busy flag.
	out	reset,al		;send reset pulse to controller.
	out	clear,al		; clear any pending ctlr interrupt.
	in	al,status		; initialization data.
movel:	lodsb				; al = byte of init data.
	out	data,al			; send init data to controller.
	loop	movel			; decrement cx, loop if not zero.
	out	intrupt,al		; interrupt controller.

	call	twait			; wait for controller request.

	; check for controller error.
	in	al,status		; if controller error,
	test	al,error
	jz	move9			; then
	mov	bx,offset msg1		; print "load aborted".
	call	prtmsg
	call	geterr			; get error bytes from controller.
	mov	bx,offset msg5		; print "check dril = status.
	test	al,error	; any errors?
	jz	data1		; hop if not.
	pop	ax		; correct stack.
	ret			; abort data phase.

data1:	out	intrupt,al	; interrupt the controller.
data2:	in	al,status	; al = status.
	test	al,ready	; is it ready?
	jz	data2		;