Atari Roots

[Bill Lange]

I've been updating Atari Roots, an Atari assembly language book from circa 1983, to include examples for DASM/ Atari800Win PLus.

 

For example, I took the following program from chapter 9, which was for the Atari Assembler Editor cartridge. I fixed the errors in line 160 and 190 (the Atari assembler can not assemble a line with just a lable on it) -

 

10; THE ATARI RAINBOW

20; RAINBOW.SRC

30;

40 COLRBK=$2C8; THE GRAPHICS 0 BORDER COLOR REGISTER

50 TMPCLR=$C0; A PLACE TO STORE COLORS TEMPORARILY

60;

70  *=$0600

80;

90 START LDA #$FE; MAX COLOR VALUE

0100  STA TMPCLR

0110;

0120 NEWCLR LDA TMPCLR

0130  STA COLRBK

0140;

0150  LDX #$FF

0160 LOOPA NOP; JUST A DELAY LOOP

0170;

0180  LDY #$30

0190 LOOPB NOP; ANOTHER DELAY LOOP

0200  DEY; DECREMENT Y REGISTER

0210  BNE LOOPB

0220;

0230  DEX; DECREMENT X REGISTER

0240  BNE LOOPA

0250;

0260  DEC TMPCLR; DCREMENT TMPCLR

0270  DEC TMPCLR; SUBTRACT 2 FOR NEXT COLOR

0280  BNE NEWCLR; IF NOT ZERO, CHANGE COLORS AGAIN

0290;

0300  JMP START; ALL COLORS DISPLAYED - NOW DO 'EM ALL AGAIN

 

 

and modified it for DASM

 

; The Atari Rainbow
; rainbow.das
; compile with DASM
; dasm rainbow.das -f3 -orainbow.bin
; attach resulting .BIN file as a cartridge in the Atari800Win Plus Emulator



       processor 6502; must be seven space before this line



COLRBK equ $2C8; THE GRAPHICS 0 BORDER COLOR REGISTER

TMPCLR equ $C0; A PLACE TO STORE COLORS TEMPORARILY



 ORG $A000



 CLD; clear the decimal flag

 CLC; clear the carry flag



START LDA #$FE; MAX COLOR VALUE

 STA TMPCLR



NEWCLR LDA TMPCLR

 STA COLRBK



 LDX #$FF

LOOPA NOP; JUST A DELAY LOOP



 LDY #$30

LOOPB NOP; ANOTHER DELAY LOOP

 DEY; DECREMENT Y REGISTER

 BNE LOOPB

 DEX; DECREMENT X REGISTER

 BNE LOOPA



 DEC TMPCLR; DECREMENT TMPCLR

 DEC TMPCLR; SUBTRACT 2 FOR NEXT COLOR

 BNE NEWCLR; IF NOT ZERO, CHANGE COLORS AGAIN



 JMP START; ALL COLORS DISPLAYED - START OVER



 ORG $BFFA

 .byte $00; $BFFA starting address low byte

 .byte $A0; $BFFB starting address high byte

 .byte $00; $BFFC cartridge present byte must be zero

 .byte $02; $BFFD cartridge flag byte - bits 0,2 and 7 are significant

 .byte $00; $BFFE init address low byte

 .byte $A0; $BFFF init address high byte

 

I've also showed how to use the Monitor in the Atari800Win Plus instead of the DEBUG mode of the Atari Assembler Editor cart.

 

Is there any interest in seeing this?

 

WRL

[+Sauron]

Yes, definitely! I've never read the original book, though, but just having specific examples for today's commonly used assemblers would be worth the price of admission in itself.

[Jetboot Jack]

I'd like to see this stuff -- I still have my copy of roots

 

sTeVE

[DEBRO]

Hi Bill,

 

Nice to see you translating this to DASM (as this is the assembler I use ).

 

BTW, I've been sitting on this for a while now...

 

Your examples will run a cart image. If you wanted to create a disk image using DASM you would do...

CODE_START = $<code start address>

RUNAD = $2E0         ; needs to be added to equates.inc



 .org CODE_START
;
; this is the header information needed for the disk image
;

 .byte $FF,$FF

 .word CODE_START   ; the code starting location

 .word CODE_END-13  ; the ending location of the code (minus DASM extra bytes)

.

.

.


;
; since I can't find a way to .org RUNAD in DASM...this works fine
; it tells DOS the start address of the code
;

 .word RUNAD,RUNAD-1

 .word CODE_START

END_CODE

[Bill Lange]

Look here -

 

http://www.langesite.com/AtariRoots/index.html

 

Thanks for the info on the disk images. I'll have to try that too.

 

WRL

[DEBRO]

Bill I forgot to add...

 

Have you seen this http://www.atariage.com/forums/viewtopic.p...6728&highlight= I hope to see you there

[Bill Lange]

I've seen it now!

 

WRL

[Bill Lange]

Ok, here is all of Atari Roots except Appendix A. Let me know what you guys think.

 

I am know in the processes of converting all the example programs to Dasm/Atari800Win PLus.

 

www.langesite.com/AtariRoots

 

WRL