[Coco] Memory Map

[Robert Gault]

Louis Ciotti wrote:
> Where can I get a memory map of the CoCo?
>
> In my initial attempt at assembly programing I first used Disk EDTASM in
> XRoar, and programed the example in the Disk EDTASM manual and it produced
> a checker board pattern on the screen like the manual said it should.  I
> then tried using lwasm, and as09 and it did not work.  I tracked the
> problem to the "ORG $1200" statement.  If I remove that line the
> program runs in XRoar as it should if assembled with lwasm, but not as09.
>
> Here is the program (Hopefully this looks ok, need a monospaced font):
>
>         org     $1200
> begin  jmp     start
>         fdb     done-begin
> start  lda     #$f9
>         ldx     #$400
> screen sta     ,x+
>         cmpx    #$600
>         bne     screen
> wait   jsr     [$a000]
>         beq     wait
>         clr     $71
>         jmp     [$fffe]
> done   equ     *
>         end
>
> The Disk TASM manual states that $1200 is used as the starting address
> because the "DOS" program for Disk EDTASM occupies from $0600 - $11FF.  Now
> if I use lwasm I of course do not have DOS in memory so $0600-$11FF is
> empty.
>

Louis,
I can see that you used the test program from the EDTASM user's manual. I 
suggest that you change it so that you can run it directly from EDTASM as 
explained in the manual.
Remove the org $1200 and replace the
      CLR
      JMP [$FFFE]
with
      SWI

Then you just assemble the program in memory and let EDTASM decide where to 
place it.
A/IM
Then enter
Z
G BEGIN

By the way, stock EDTASM does not like lower case.