Joshua Wise's Git repositories - fpgaboy.git/blame_incremental

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Commit	Line	Data
	1	SECTION "a",HOME
	2
	3	main:
	4	ld c, $51 ; Note that we are alive.
	5	ld a, $FF
	6	ld [c],a
	7
	8	ld sp, $DFFF
	9
	10	ld hl, signon
	11	call puts
	12
	13	call memtest
	14
	15	call insntest
	16
	17	call waitsw
	18
	19	jr main
	20
	21	signon:
	22	db $0D,$0A,$1B,"[1mFPGABoy Diagnostic ROM",$1B,"[0m",$0D,$0A,0
	23
	24	; Memory tester: writes h ^ l to all addresses from C000 to DF80.
	25	memtest:
	26	ld hl,memteststr
	27	call puts
	28
	29	ld hl, $C000 ; Write loop
	30	.wr:
	31	ld a,h
	32	xor l
	33	ld [hli],a
	34	ld a, $DF
	35	cp h
	36	jr nz, .wr
	37	ld a, $80
	38	cp l
	39	jr nz, .wr
	40
	41	ld hl, $C000 ; Read loop
	42	.rd:
	43	ld a,h
	44	xor l
	45	ld b,a
	46	ld a, [hli]
	47	cp b
	48	jr nz, .memfail
	49
	50	ld a, $DF
	51	cp h
	52	jr nz, .rd
	53	ld a, $80
	54	cp l
	55	jr nz, .rd
	56
	57	ld hl, testokstr ; Say we're OK
	58	call puts
	59	ret
	60	.memfail: ; Say we failed (sadface)
	61	; decrement hl the easy way
	62	ld a,[hld]
	63	push hl
	64	ld hl, failatstr
	65	call puts
	66	pop hl
	67	ld a, h
	68	call puthex
	69	ld a, l
	70	call puthex
	71	ld a, $0A
	72	call putc
	73	ld a, $0D
	74	call putc
	75	ret
	76	memteststr:
	77	db "Testing memory from $C000 to $DF80...",0
	78	testokstr:
	79	db " OK!",$0D,$0A,0
	80	failatstr:
	81	db " Test failed at $",0
	82
	83	puthex: ; Put two hex nibbles to the serial console.
	84	push af
	85	rra
	86	rra
	87	rra
	88	rra
	89	ld b,$0F
	90	and b
	91	ld b,$30
	92	add b
	93	call putc
	94	pop af
	95	ld b,$0F
	96	and b
	97	ld b,$30
	98	add b
	99	call putc
	100	ret
	101
	102	; Wait for switches to be flipped on and off again.
	103	waitsw:
	104	ld hl,waitswstr
	105	call puts
	106
	107	ld c, $51
	108	ld a, $00
	109	ld [c],a
	110
	111	ld c, $51
	112	ld b, $0
	113	.loop1:
	114	ld a,[c]
	115	cp b
	116	jr z,.loop1
	117	.loop2:
	118	ld a,[c]
	119	cp b
	120	jr nz,.loop2
	121	ret
	122
	123	waitswstr:
	124	db "Diagnostic ROM complete; flip switches to nonzero and then to zero to reset.",$0D,$0A,0
	125
	126	; Core instruction basic acceptance tests.
	127	insntest:
	128	ld hl, .insnteststr
	129	call puts
	130
	131	; Test PUSH and POP.
	132	ld b, $12
	133	ld c, $34
	134	ld d, $56
	135	ld e, $78
	136	push bc
	137	pop de
	138	ld hl, .pushpopfail
	139	ld a, d
	140	cp b
	141	jr nz,.fail
	142	ld a, e
	143	cp c
	144	jr nz,.fail
	145
	146	; Test ALU (HL).
	147	ld hl, .ff
	148	ld a, $FF
	149	xor [hl]
	150	ld hl, .xorhlfail
	151	jr nz, .fail
	152
	153	; Test JP (HL)
	154	ld hl, .jphl
	155	jp [hl]
	156	ld hl, .jphlfail
	157	jr .fail
	158	rst $00
	159	.jphl:
	160
	161	; Test JR
	162	ld a, $FF
	163	ld b, $00
	164	cp b
	165	jr nz,.jr
	166	ld hl, .jrfail
	167	jr .fail
	168	rst $00
	169	.jr:
	170
	171	; Test CP.
	172	ld hl, .cpfail
	173	ld a, $10
	174	ld b, $20
	175	cp b
	176	jr nc,.fail
	177	ld a, $20
	178	ld b, $10
	179	cp b
	180	jr c,.fail
	181
	182	; Test CPL
	183	ld hl, .cplfail
	184	ld a, $55
	185	ld b, $AA
	186	cpl
	187	cp b
	188	jr nz,.fail
	189
	190	ld hl, .ok
	191	call puts
	192	ret
	193	.fail:
	194	call puts
	195	ret
	196	.insnteststr:
	197	db "Testing instructions... ",$0
	198	.pushpopfail:
	199	db "PUSH/POP test failed.",$0D,$0A,0
	200	.ff:
	201	db $FF
	202	.xorhlfail:
	203	db "XOR [HL] test failed.",$0D,$0A,0
	204	.jphlfail:
	205	db "JP [HL] test failed.",$0D,$0A,0
	206	.jrfail:
	207	db "JR test failed.",$0D,$0A,0
	208	.cpfail:
	209	db "CP test failed.",$0D,$0A,0
	210	.cplfail:
	211	db "CPL test failed.",$0D,$0A,0
	212	.ok:
	213	db "OK!",$0D,$0A,0
	214
	215	; Serial port manipulation functions.
	216	putc:
	217	push af
	218	ld b, 0
	219	ld c, $50
	220	.waitport:
	221	ld a,[c]
	222	cp b
	223	jr nz,.waitport
	224	pop af
	225	ld [c],a
	226	ret
	227
	228	puts:
	229	ld a, [hli]
	230	ld b, $00
	231	cp b
	232	jr z, .done
	233	call putc
	234	jr puts
	235	.done:
	236	ret
	237