; code: language=z80-asm tabSize=8

; SIMULATE_ERROR = $80
; SIMULATE_ERROR = $3C

.include "inc/z80.mac"
.include "inc/spt.mac"

; Notes on global register allocation:
;
; This ROM doesn't work like typical Z80 code, which assumes the presence of a stack.
; There may in fact be no working memory in the machine for holding the stack.
;
; An overall goal for this version of the code is to run in the absence of any working
; ram at all.  There is no stack and no RAM variables.  The only storage of variables
; is in registers, so the registers must be carefully preserved.
;
; Without a stack, that means either saving them to other registers and restoring before 
; jumping to other code (remembering there can be no CALLs when there is no stack) 
; or avoiding their use altogether.  These are extremely confining restrictions.
;
; Assembly purists will shudder at the extensive use of macros, but for sanity it
; cannot be avoided.
;
; Globally, the contents of these registers must be preserved
;	e = bit errors in the region of memory currently being tested
;	ix = current location in VRAM for printing messages
;	iy = current table entry for test parameters
;

VBASE  equ 03000h
VSIZE  equ 0ffeh
VLINE  equ 80


		.org 0000h				; z80 boot code starts at location 0
reset:
		di					; mask INT
		im	1

diagnostics:
	xor a

	out (0c0h),a		;0046 clear io, floppy control
	out (0c4h),a		;0048 clear io,Program map A base
	out (0c5h),a		;004a clear io,Program map B base
	out (0c6h),a		;004c clear io,DMA map A base
	out (0c7h),a		;004e clear io,DMA map B base
	out (0d4h),a		;0050 clear io,Hi-res color
	out (0d8h),a		;0052 clear io,Hi-res start
	ld hl,set_regs_start
	jp set_monroe_regs
init_continue:

	jp setupclearscreen
screen_clear_continue:
	ld a,080h			;
	out (0d4h),a		; Setup Screen
	ld a,005h			;
	out (0a3h),a		; DART B command
	ld a,068h			;
	out (0a3h),a		; DART B command
	ld a,0f0h			; ?????
	out (0c8h),a		; Map and system control
	;select screen memory
	ld a,004h			; Select display memory
	out (0c8h),a		; Output to screen Map and system control

test_vram:
		SPTHREAD_BEGIN				; set up to begin running threaded code
		SPT_SKIP_NMIVEC
		dw spt_playmusic, tones_welcome

		dw spt_select_test, tp_vram
		dw memtestmarch				; test the VRAM
		dw spt_check_7bit_vram
		; dw spt_sim_error, $40
		dw spt_jp_nc, .vram_ok

		; we have bad vram
		dw spt_prepare_display
		dw spt_chartest
	.vram_bad_loop:
		;dw spt_play_testresult			; play the tones for bit errorssetupcrt
		;dw spt_pause, $0000
		dw spt_jp,.vram_bad_loop

	.vram_7bit:
		dw spt_con_print, msg_ok7bit
		; dw spt_play_testresult			; play the tones for bit errors
		;dw spt_jp,.vram_goodtones

	.vram_ok:
		dw spt_prepare_display
		MAC_SPT_CON_GOTO 2,0
		dw spt_announcetest2 			; print results of VRAM tst
		; dw print_biterrs
		dw spt_jp_e_7bit_vram, .vram_7bit
		dw spt_con_print, msg_ok8bit

	.vram_goodtones:
		;dw spt_playmusic, tones_vramgood	; play the VRAM good tones

	.vram_continue:
		MAC_SPT_CON_GOTO 1,0
		dw spt_check_size

		dw spt_jp_256_fail, .skip256

		dw spt_con_print, msg_256k
		dw spt_select_test, tp_16k_256			; load the first test
		dw spt_jp, .start
	.skip256:
		dw spt_con_print, msg_128k
		dw spt_select_test, tp_16k			; load the first test
		dw spt_jp, .start


	.start:	dw spt_con_goto
				MAC_SPT_CON_OFFSET 3,0

	.loop:	dw spt_announcetest 			; announce what test we are about to run

		dw memtestmarch2				; test the current bank
		dw spt_jp_nc, .ok
		
		dw spt_con_print, msg_biterrs		; we have errors: print the bit string
		dw print_biterrs
		;dw spt_play_testresult			; play the tones for bit errors
		dw spt_jp, .cont
	
	.ok:	dw spt_con_print, msg_testok		; bank is good: print the OK message
		;dw spt_play_testresult			; play the tones

	.cont:
		dw spt_tp_next, .start
		dw spt_jp, .loop


;; -------------------------------------------------------------------------------------------------
;; end of main program.

spt_prepare_display:
		SPTHREAD_ENTER
		dw con_clear
		dw spt_con_print, msg_banner		; print the banner
		dw spt_print_charset
		dw spt_exit
spt_check_size:
		; Check if 256k memory or 128k
		ld hl,0c000h	; Point to test address
		ld a,0a0h		; Memory bank
		ld b,$FF		; B = FF
		out (0c5h),a	;
		ld (hl),b		;	
		inc a			; A = A1
		out (0c5h),a	;
		ld (hl),b		;
		dec a			; A = A0
		add b			; B = 00

		out (0c5h),a	; Select memory bank 9
		ld (hl),b		;
		dec b			; B = FF
		inc a			; A = A1
		out (0c5h),a	; Select memory bank 1
		ld (hl),b		;
		dec a			; A = A0
		out (0c5h),a	; Select memory bank 9
		ld b,(hl)		; If 256kb B should be 0

		ret
spt_check_vram_contents:
		pop	bc
		ld	a,b
		ld	d,c

; confirm that all of VRAM contains the value in register A
check_vram_contents:
		ld	hl,VBASE
		ld	bc,VSIZE
	.fillloop:
		ld	(HL),a
		cpi
		jp	pe,.fillloop

		ld	hl,VBASE
		ld	bc,VSIZE
		ld	a,d
	.readloop:
		cpi
		jr	nz,.bad
		jp	pe,.readloop

		or	a	; clear carry flag
		ret
	.bad:	scf
		ret

spt_check_7bit_vram:
		ret	nc				; if carry flag is not set, do nothing
		ld	a,01000000b
		cp	e
		jr	z,.scantests
		scf					; something other than bit 6 is bad, so this is not 7bit VRAM
		ret
	.scantests:
		SPTHREAD_ENTER
		dw spt_check_vram_contents, $0040
		dw spt_jp_c, .exit
		dw spt_check_vram_contents, $FFBF
		dw spt_jp_c, .exit
		dw spt_check_vram_contents, $AAAA
		dw spt_jp_c, .exit
		dw spt_check_vram_contents, $5555
		dw spt_jp_c, .exit
	.exit:	dw spt_exit				; if carry flag is set, this is not good 7-bit VRAM


spt_sim_error:
		pop	de
		scf
		ret


; test if the error is $FF (all bits bad)
spt_jp_256_fail:
		pop	hl				; get the address for jumping if match
		inc b
		ret	nz				; return without jump if there is NOT a match
		ld	sp,hl				; else jump to the requested location
		ret

; test if the e register matches 7-bit vram and jump to spt address if match
spt_jp_e_7bit_vram:
		pop	hl				; get the address for jumping if match
		ld	a,01000000b			; ignore bit 6
		cp	e				; see if there are other errors
		ret	nz				; return without jump if there is NOT a match
		ld	sp,hl				; else jump to the requested location
		ret

; test if the e register matches 7-bit vram and jump to spt address if match
spt_jp_e_zero:
		pop	hl				; get the address for jumping if match
		ld	a,0				; test clean
		cp	e				; see if there are other errors
		ret	nz				; return without jump if there is NOT a match
		ld	sp,hl				; else jump to the requested location
		ret

; load the label string address from the current test parameter table entry into hl
spt_ld_hl_tp_label:
		ld	l,(iy+4)
		ld	h,(iy+5)
		ret

; load the label string address from the current test parameter table entry into hl
spt_ld_hl_tp_tones:
		ld	l,(iy+6)
		ld	h,(iy+7)
		ret

spt_ld_new_line:
		ld	a,(iy+9)
		ld ixh,a
		ld	a,(iy+8)
		ld ixl,a
		ret
; move to the next test parameter table entry
spt_tp_next:	pop	hl				; get the address to jump to if we are starting over
		ld 	bc,tp_size			; find the next entry
		add 	iy,bc
		ld	a,(iy+0)			; is the length zero?
		add	a,(iy+1)
		ret	nz				; no, use it
		ld	c,(iy+2)			; yes, get the address of the first entry
		ld	b,(iy+3)
		ld	iy,0
		add	iy,bc
		; sub	a				; clear zero flag when restarting
		ld	sp,hl				; jump to the next location
		ret

spt_announcetest:
		; pop	hl				; get the message to be printed
		SPTHREAD_ENTER
		dw spt_ld_new_line

		;dw con_NL

		dw spt_ld_hl_tp_label
		dw con_print				; picks up message from hl
		dw spt_con_print, msg_testing
		dw spt_con_index, -18
		dw spt_exit

spt_announcetest2:
		; pop	hl				; get the message to be printed
		SPTHREAD_ENTER

		dw spt_ld_hl_tp_label
		dw con_print				; picks up message from hl
		dw spt_con_print, msg_testing
		dw spt_con_index, -18
		dw spt_exit
spt_play_testresult:
		SPTHREAD_SAVE				; save the stack pointer

		SPTHREAD_BEGIN
		dw spt_ld_hl_tp_tones			; play the ID tune for current bank
		;dw playmusic
		dw spt_pause, $2000
		SPTHREAD_END

		ld	a,$FF
		cp	e
		jr	z,.allbad			; if all bits bad, play shorter tune

		cpl
		cp	e
		jr	z,.allgood			; if all bits good, play shorter tune

		ld	d,8				; play bit tune for each bit, high to low
	.showbit:
		rlc	e
		jr	nc,.zero
		ld	hl,tones_bitbad
		jr	.msbe_cont
	.zero:
		ld	hl,tones_bitgood
	.msbe_cont:
		SPTHREAD_BEGIN
		;dw playmusic
		dw spt_pause, $2000
		SPTHREAD_END

		; pause $4000
		dec	d
		jr	nz,.showbit
		jr	.done
	.allbad:
		SPTHREAD_BEGIN
		;dw spt_playmusic, tones_bytebad
		dw spt_pause, $8000
		SPTHREAD_END
		jr	.done
	.allgood:
		SPTHREAD_BEGIN
		;dw spt_playmusic, tones_bytegood
		dw spt_pause, $8000
		SPTHREAD_END
	.done:
		SPTHREAD_RESTORE			; restore the stack pointer
		ret


spt_pause:
		pop	bc
; pause by an amount specified in BC
pause_bc:
	.loop:
		dec	bc
		ld	a,b
		or	c
		jr	nz,.loop
		ret



print_biterrs:

		ld a,004h			; Select display memory
		out (0c8h),a		; Output to screen Map and system control		
		ld	a,'7'
		ld	b,8
	.showbit:
		rlc	e
		jr	nc,.zero
		ld	(ix+1),a
		jr	.cont
	.zero:
		ld	(ix+1),'.'
	.cont:
		inc	ix
		inc	ix
		dec	a
		djnz	.showbit
		xor a				;054b Reset map
		out (0c8h),a		;054c Reset to memory Map and system control
		ret

spt_ld_bc:	pop 	bc
		ret


spt_print_charset:
	
		ld	a,ixh
		ld	h,a
		ld	a,ixl
		ld	l,a
		ld	a,0
		SPTHREAD_ENTER
		MAC_SPT_CON_GOTO 15,24
		dw spt_con_print, msg_charset		; show a copy of the character set
		MAC_SPT_CON_GOTO 16,0
		dw spt_ld_bc, $100
		dw do_charset_ix
		dw spt_exit

spt_chartest:
	ld	ix,VBASE
	ld	bc,VSIZE

do_charset_ix:
	ld a,004h			; Select display memory
	out (0c8h),a		; Output to screen Map and system control	
	ld a,32
	.charloop:
		ld	(ix+1),a	; copy A to byte pointed by HL
		inc	a		; increments A
		inc	ix
		inc ix
		cpi			; increments HL, decrements BC (and does a CP)
		jp	pe, .charloop
		xor a				;054b Reset map
		out (0c8h),a		;054c Reset to memory Map and system control		
		ret
screenclearloop:
	otir		;0560  out B bytes from (HL) to (C)
set_monroe_regs:
	ld c,(hl)			; get register
	inc hl			;  bump
	ld b,(hl)			;get count
	inc hl			; bump
	ld a,b			;
	and a			;
	jr nz,screenclearloop		;0568 if count not 0 loop $-8
	jp init_continue	
setupclearscreen:
;entry during initiation w
	xor a			; start A=0
	ld bc,00eb9h		; C=B9 B=14
	ld hl,set_up_crt		;

setupclearloop:
	out (0b8h),a				;CRT register select
	inc a						;  A++
	outi						; C)=(HL++) and B--
	jr nz,setupclearloop 		; loop until B==0 (14 bytes to write) $-5
	jp screen_clear_continue

label_vram:	dbz " 4K VRAM 3000-3FFE "
label_dram16k1:	dbz "16K DRAM 0 C000-FFFF "
label_dram16k2:	dbz "16K DRAM 1 "
label_dram16k3:	dbz "16K DRAM 2 "
label_dram16k4:	dbz "16K DRAM 3 "
label_dram16k5:	dbz "16K DRAM 4 "
label_dram16k6:	dbz "16K DRAM 5 "
label_dram16k7:	dbz "16K DRAM 6 "
label_dram16k8:	dbz "16K DRAM 7 "

label_dram64k1:	dbz " 0K DRAM 0 C000-FFFF "
label_dram64k2:	dbz "16K DRAM 0 "
label_dram64k3:	dbz "32K DRAM 0 "
label_dram64k4:	dbz "48K DRAM 0 "
label_dram64k5:	dbz " 0K DRAM 1 "
label_dram64k6:	dbz "16K DRAM 1 "
label_dram64k7:	dbz "32K DRAM 1 "
label_dram64k8:	dbz "48K DRAM 1 "

label_dram64k9:		dbz " 0K DRAM 2 "
label_dram64k10:	dbz "16K DRAM 2 "
label_dram64k11:	dbz "32K DRAM 2 "
label_dram64k12:	dbz "48K DRAM 2 "
label_dram64k13:	dbz " 0K DRAM 3 "
label_dram64k14:	dbz "16K DRAM 3 "
label_dram64k15:	dbz "32K DRAM 3 "
label_dram64k16:	dbz "48K DRAM 3 "
msg_banner:	dbz "Monroe OC8820 TEST ROM -- FRANK IZ8DWF / DAVE KI3V / ADRIAN BLACK"
msg_charset:	dbz "-CHARACTER SET-"
; msg_testing:	db " ", " "+$80, "t"+$80, "e"+$80, "s"+$80, "t"+$80, " "+$80, "  ", 0
msg_testing:	dbz "..TEST.. "
msg_128k:	dbz "128K machine"
msg_256k:	dbz "256K machine"
msg_testok:	dbz "---OK--- "
msg_biterrs:	dbz "BIT ERRS "
msg_ok7bit:	dbz "OK! (7-BIT MODEL 1)"
msg_ok8bit:	dbz "OK! (8-BIT)"



; test parameter table. 2-byte entries:
; 1. size of test in bytes
; 2. starting address
; 3. address of string for announcing test
; 4. address of tones for identifying the test audibly
tp_size		equ	10

memtest_ld_bc_size .macro
		ld	c,(iy+0)
		ld	b,(iy+1)
.endm

memtest_ld_hl_base .macro
		ld	l,(iy+2)
		ld	h,(iy+3)
.endm

memtest_loadregs .macro
		memtest_ld_bc_size
		memtest_ld_hl_base
.endm

spt_ld_iya6 .macro 
		ld	a,(iy+6)
.endm

spt_ld_iya7 .macro
		ld	a,(iy+7)
.endm

tp_vram:	dw	VSIZE, VBASE, label_vram, tones_vram


tp_16k:		dw	$4000, $C000, label_dram16k1,  $a100,$31e0
			dw	$4000, $C000, label_dram16k2,  $c100,$3280
			dw	$4000, $C000, label_dram16k3,  $e100,$3320
			dw	$4000, $C000, label_dram16k4,  $0000,$33c0
			dw	$4000, $C000, label_dram16k5,  $2000,$3460
			dw	$4000, $C000, label_dram16k6,  $4000,$3500
			dw	$4000, $C000, label_dram16k7,  $6000,$35a0
			dw	$4000, $C000, label_dram16k8,  $8000,$3640
			dw	$0000, tp_16k

tp_16k_256:	dw	$4000, $C000, label_dram64k1,  $a100,$31e0
			dw	$4000, $C000, label_dram64k2,  $c100,$3280
			dw	$4000, $C000, label_dram64k3,  $e100,$3320
			dw	$4000, $C000, label_dram64k4,  $0000,$33c0
			dw	$4000, $C000, label_dram64k5,  $2000,$3460
			dw	$4000, $C000, label_dram64k6,  $4000,$3500
			dw	$4000, $C000, label_dram64k7,  $6000,$35a0
			dw	$4000, $C000, label_dram64k8,  $8000,$3640
			dw	$4000, $C000, label_dram64k9,  $a000,$3230
			dw	$4000, $C000, label_dram64k10, $c000,$32d0
			dw	$4000, $C000, label_dram64k11, $e000,$3370
			dw	$4000, $C000, label_dram64k12, $0100,$3410
			dw	$4000, $C000, label_dram64k13, $2100,$34b0
			dw	$4000, $C000, label_dram64k14, $4120,$3550
			dw	$4000, $C000, label_dram64k15, $6100,$35f0
			dw	$4000, $C000, label_dram64k16, $8100,$3690
			dw	$0000, tp_16k_256
	
set_regs_start:
	defb 0b5h		;005a io port CRT register select
	defb 004h		;005b count 4
	defb 0cfh		;005c
	defb 0b8h		;005d
	defb 037h		;005e
	defb 0efh		;005f
	;
	defb 0b4h		;0060 io port PIO A data
	defb 001h		;0061 count 1
	defb 001h		;0062
	;
	defb 0a1h		;0063 io port DART A command
	defb 006h		;0064 count 6
	defb 048h		;0065
	defb 048h		;0066
	defb 004h		;0067
	defb 044h		;0068
	defb 005h		;0069
	defb 0eah		;006a
	;
	defb 0a3h		;006b io port DART B command
	defb 008h		;006c count 8
	defb 048h		;006d
	defb 048h		;006e
	defb 004h		;006f
	defb 044h		;0070
	defb 001h		;0071
	defb 000h		;0072
	defb 003h		;0073
	defb 0c1h		;0074
	;
	defb 0a5h		;0075 io port SIO A command
	defb 002h		;0076 count 2
	defb 048h		;0077
	defb 048h		;0078
	;
	defb 0a7h		;0079 io port SIO B command
	defb 002h		;007a count 2
	defb 048h		;007b
	defb 048h		;007c
	;
	defb 0a8h		;007d io port CTC CHANNEL 0 - Communications baud rate
	defb 002h		;007e count 2
	defb 003h		;007f
	defb 003h		;0080
	;
	defb 0a9h		;0081 io port CTC CHANNEL 1 - AUX RS-232C baud rate
	defb 002h		;0082 count 2
	defb 003h		;0083
	defb 003h		;0084
	;
	defb 0aah		;0085 io port  CTC CHANNEL 2 - Printer baud rate
	defb 002h		;0086 count 2
	defb 057h		;0087
	defb 04eh		;0088
	;
	defb 000h		;0089 io port reset
	defb 000h		;008a count 0 terminator

set_up_crt:
;data to be output to io port B9 14 byte CRT data register
	defb 069h		;054f
	defb 050h		;0550
	defb 056h		;0551
	defb 00bh		;0552
	defb 019h		;0553
	defb 003h		;0554
	defb 018h		;0555
	defb 018h		;0556
	defb 000h		;0557
	defb 00bh		;0558
	defb 020h		;0559
	defb 000h		;055a
	defb 000h		;055b
	defb 000h		;055c

include "inc/spt.asm"
include "inc/memtestmarch.asm"
include "inc/monroecon.asm"
include "inc/trs80music.asm"