problem with lesson 21

Hi

I added a picture to the program in tutorial 21 and I got an error.

Quote

vars    [u] 0080 0080

   0000 ????    0000 ????

RIOT    [u] 0280 0280

TIA_REGISTERS_READ    [u] 0000 0000

TIA_REGISTERS_WRITE [u] 0000 0000

INITIAL CODE SEGMENT    0000 ????    0000 ????

----------------------------------------------------------------------
12 references to unknown symbols.
17 events requiring another assembler pass.
- Expression in mnemonic not resolved.
- Label defined after it has been referenced (forward reference).

Unrecoverable error(s) in pass, aborting assembly!
Complete.

Here the code:

Quote

; '2600 for Newbies
; Session 21 - Sprites
; This kernel draws a simple box around the screen border
; Introduces sprites

processor 6502
include "vcs.h"
include "macro.h"

SpriteHeight = 8

SEG.U vars
ORG $80

SpriteXPosition ds 1
PlayerX    ds 2    ; x coordinate
PS_temp ds 1
Sprite ds 2
SpriteEnd ds 1

;------------------------------------------------------------------------------

SEG code
ORG $F000

Reset

; Clear RAM and all TIA registers

ldx #0
lda #0
Clear    sta 0,x
inx
bne Clear

ldx #$FF
txs

;------------------------------------------------
; Once-only initialisation...

lda #$45
sta COLUPF ; set the playfield colour

lda #$56
sta COLUP0
lda #$67
sta COLUP1

lda #%00000001
sta CTRLPF ; reflect playfield
lda #80
sta PlayerX+1
lda #60
sta SpriteEnd
lda #<Sprite0Data
sta Sprite
lda #>Sprite0Data
sta Sprite+1

;------------------------------------------------

StartOfFrame

; Start of vertical blank processing

lda #0
sta VBLANK

lda #2
sta VSYNC

; 3 scanlines of VSYNCH signal...

sta WSYNC
sta WSYNC
sta WSYNC

lda #0
sta VSYNC
sta WSYNC

; 37 scanlines of vertical blank...

ldx #0
VerticalBlank sta WSYNC
inx
cpx #37 ; Now waiting 37 lines
bne VerticalBlank

DrawField
ldx #0    ; this counts our scanline number

;line 1 - score player 0
   lda #$90
   sta COLUPF ; set the playfield colour
   ;lda #$00
   ;sta COLUBK ; set the background colour
   lda #%11111111
   sta PF0
   sta PF1
   sta PF2

linescr
sta WSYNC
inx
cpx #16
bne linescr

;ligne 1
   lda #$2E
   sta COLUPF ; set the playfield colour
   lda #$00
   sta COLUBK ; set the background colour
   lda #%11111111
   sta PF0
   sta PF1
   sta PF2

line1
sta WSYNC
inx
cpx #24
bne line1

;line 2a
   lda #$2E
   sta COLUPF ; set the playfield colour
   lda #$42
   sta COLUBK ; set the background colour
   lda #%00011000
   sta PF0
   lda #%0
   sta PF1
   sta PF2

line2a
sta WSYNC
inx
cpx #168
bne line2a

;line 2l
lda #$2E
sta COLUPF ; set the playfield colour
lda #$00
sta COLUBK ; set the background colour
lda #%11111111
sta PF0
sta PF1
sta PF2

line2l
sta WSYNC
inx
cpx #176
bne line2l

:Last line
lda #$90
sta COLUBK ; set the background colour
lda #%0
sta PF0
sta PF1
sta PF2

LastLine
sta WSYNC
inx
cpx #192
bne LastLine

; again, we don't bother writing PF0-PF2 every scanline - they never change!

sta WSYNC

MiddleLines
TXA; transfer scanline count to A
   SEC; well for this example I don't know the state
SBC SpriteEnd; so that's 96 - 96 = 0
adc #SpriteHeight ;remember the sprite is 8 lines high
bcc .skipMBDraw3 ;out of range???
tay
lda (Sprite),y   ; use indirect loading here
sta GRP0
;sec ; 2 can often be guaranteed, and omitted
   ;tya ; 2
;sbc SpriteEnd ;3
   ;adc #SpriteHeight ;2
   ;bcs .MBDraw3 ;2(3)
   ;nop    ;2
   ;nop    ;2
   ;sec    ;2
   ;bcs .skipMBDraw3 ;3
.MBDraw3
;tay
;lda (Sprite),Y ;5
   ;sta GRP0 ;3
.skipMBDraw3

sta WSYNC
;inx
dey
dex
bne MiddleLines

lda #0
sta GRP0
sta GRP1

lda #%01000010
sta VBLANK ;end of screen - enter blanking

; 30 scanlines of overscan...

ldy #0
sty PF0
sty PF1
sty PF2
Overscan sta WSYNC
iny
cpy #23
bne Overscan
inc SpriteEnd
ldx SpriteEnd
cpx #192
bcc LT192
ldx #0
stx SpriteEnd
LT192
; Now adjust the sprite position

inc PlayerX
ldx PlayerX
cpx #150
bcc LT160
ldx #0
stx PlayerX

LT160
dec PlayerX+1
ldx PlayerX+1
bne GT0
ldx #150
stx PlayerX+1

GT0
jsr PositionSprites

jmp StartOfFrame

PositionSprites

; Set the horizontal position of the two sprites, based upon their coordinates
; This uses the tricky 2600 method of positioning (RESPx, HMPx, etc)

; Algorithm invented a looong time ago by persons unknown
; Re-invented Feb2001 by yours truly, then optimised according to code by Thomas Jenztsch

sta WSYNC
sta HMCLR    ; clear any previous movement

ldx #2 ; sprite index
PosSP
lda PlayerX-1,x

tay

lsr
lsr
lsr
lsr

sta PS_temp

tya
and #15

clc
adc PS_temp

ldy PS_temp

cmp #15
bcc NH
sbc #15
iny
NH

; Use remainder for fine adjustment
eor #7
asl
asl
asl
asl

sta HMP0-1,x ; fine movement
sta WSYNC

jsr Ret
bit 0    ; 15 cycles = 3 loops

Jiggle dey
bpl Jiggle

sta RESP0-1,x

dex
bne PosSP

sta WSYNC
sta HMOVE
sta WSYNC
rts

Ret
rts

Sprite0Data
.byte #%00000000
.byte #%10101010
.byte #%01010101
.byte #%10101010
.byte #%01010101
.byte #%10101010
.byte #%01010101
.byte #%00000000

;------------------------------------------------------------------------------

ORG $FFFA

InterruptVectors

.word Reset    ; NMI
.word Reset    ; RESET
.word Reset    ; IRQ

END

Thanks in advance

Edited by Serguei2, Wed Jul 13, 2005 8:59 PM.

Hi there!

Serguei2, on Thu Jul 14, 2005 2:58 AM, said:

I added a picture to the program in tutorial 21 and I got an error.

Well, the actual errors were not in the lines you posted from the report, but straight above that:

test.s (169): error: Unknown Mnemonic 'Last'.
test.s (335): error: Unknown Mnemonic '#%00000000'.
test.s (336): error: Unknown Mnemonic '#%10101010'.
test.s (337): error: Unknown Mnemonic '#%01010101'.
test.s (338): error: Unknown Mnemonic '#%10101010'.
test.s (339): error: Unknown Mnemonic '#%01010101'.
test.s (340): error: Unknown Mnemonic '#%10101010'.
test.s (341): error: Unknown Mnemonic '#%01010101'.
test.s (342): error: Unknown Mnemonic '#%00000000'.

Basically you used : to uncomment a line instead of ; here

:Last line

and need to tab your table here:

	.byte #%00000000
	.byte #%10101010
	.byte #%01010101
	.byte #%10101010
	.byte #%01010101
	.byte #%10101010
	.byte #%01010101
	.byte #%00000000

Greetings,
Manuel

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