*****************************************************************
*								* 
*    MORROW 68K SYSTEM boot EPROM REV 0.			* 
*								*
*    initial coding:  5/15/84 -bjg-				*
*      								* 
*****************************************************************



ioaddr	=	$ff0000			* compupro i/o address space


***********************************
*  Compupro interfacer IV equates *
***********************************

sio	=	ioaddr+$10		* interfacer base address
siostat	=	sio+$1			* uart status
siodat  =	sio			* uart data 
select	=	sio+$7			* group select port
console =	7			* interface left port

**********************
*   mult i/o equates *
**********************

base	=	ioaddr+$48		* standard base address
grpctl	=	base+$7			* select port
dll	=	base			* divisor latch lsb
dlm	=	base+$1			* divisor latch msb
ier	=	base+$1			* interrupt enable register
lcr	=	base+$3			* line control register
mcr	=	base+$4			* modem control register
lsr	=	base+$5			* line status register 
rbr	=	base			* receive buffer register
thr	=	base			* trasnmitter holding register

dlab	=	$80			* divisor latch access bit
thre	=	$20			* transmitter hold reg empty status
dr	=	$1			* received data ready status

********************
* SIO4/DMA equates *
********************

* sio port assignments

sbase	=	ioaddr+$20 		* SIO4 base I/O address

dmaddrl =	sbase			* low byte dma address
dmaddrh	=	sbase+$1		* high byte dma address
dmaddre =	sbase+$2		* extended byte of dma address
recntrl =	sbase+$3		* receiver control port
lcount	=	sbase+$4		* low byte of dma  count	
hcount  =       sbase+$5		* high byte of dma count
enable  =	sbase+$6		* start / stop enable
dmacntl =	sbase+$7		* dma control and status
sdata	=	sbase+$8		* uart data port
sstatus =	sbase+$9		* uart status port
smode	=	sbase+$a		* uart mode register
scommnd =	sbase+$b		* uart command register	
fifost  =	sbase+$c		* fifo status
fifoda	=	sbase+$d		* fifo data
dmaglbl = 	sbase+$e		* global dma status
sselect =	sbase+$f		* tty select port

* sio constants

control =	$27		        * normal async mode
ttya	=	0			* select byte for ttya
ttyb	=	1			* select byte for tttb
ttyc	=	2			* select byte for tttc
ttyd	=	3			* select byte for tttd
divisor =	$d			*  9600 baud divisor
					*  1200 baud divisor = $8
					* 19200 baud divisor = $e

* sio flags and masks

done	=	$40			* DMA idle when port 27 = 40
sro	=	$1			* transmit buffer empty when high
sr1	=	$2			* receive buffer full when high
sr6	=	$40			* carrier detected when low
sr7	=	$80			* data set ready when low
kick	=	1			* value to kick controller



***************************
*  miscellaneous equates  *
***************************

alf	=	$a			* ascii line feed
acr	=	$d			* ascii carriage return
asp	=	$20			* ascii space
acs	=	$1a			* ascii clear for ADM31
qpat	=	$AA55			* initial ram test pattern
spat	=	$00ff	 		* marching pattern
stop	=	$F0000			* end of 2 Meg ramtest area
page	=	1024			* 2K X 8 ram chips
image	=	0
uerr	=	$4fe

*************************
*	B E G I N	*
*************************

			
* set baud rates for all four SIO4 ports
* 9600 baud, async, no parity, 8 data and 2 stop bits

sbaud:	move.b	#ttya,d2		* select uart 0
sbaud1:	move.b	d2,sselect		* select the tty
	move.b 	scommnd,d0		* set up for uart mode reg. 1	
	move.b  smode,d1		* read mode register 1 point to 2      
	move.b	smode,d0		* read mode register 2 point to 1
	move.b	smode,d1		* read mode register 1 setup for 2
	andi.b  #$f0,d0			* strip baud rate off
	ori.b	#divisor,d0		* lower 4 bits = 9600 baud
	move.b  d0,smode		* write register 2
	move.b  #control,scommnd	* set it for normal async rs232
	addq.b	#1,d2			* next one
	cmpi.b	#4,d2
	bne	sbaud1


* 	PRINT SIGNON

init1:	move.l	#signon,a1		* say hello
	move.l	#ramtest,a6		* set up return through a6
	bra	string


* check for good ram before using stack

ramtest: 
	move.l	#0,a0			* beginning of ram
	move.w	#qpat,d0		* ramtest pattern
ramtst1:
	move.w	d0,(a0)			* write it
	cmp	d0,(a0)			* check it
	bne	ramerr
	swap.b	d0			* complement
	move.w	d0,(a0)			* write it
	cmp	d0,(a0)			* read it
	bne	ramerr
	addq.l	#1,a0			* increment ram address
	bra	ramtst1

ramerr:
	cmpi.l	#0,a0			* check for no memory 
	bne	ramer2
	move.l	#ramer1,a6
	move.l	#rerr1,a1		* no ram message
	bra	string
ramer1: halt

ramer2:	move.l	a0,a7			* set up stack
	bsr	paddr			* print address				
	move.l	$rerr2,a1		* 																
	move.l	#main,a6		* return to main	
	bra	string


main:	jmp	main