[Coco] Assembly help: Corrupted bin file ?

[Roger Taylor]

At 01:30 AM 12/17/2008, you wrote:

>Hello everyone,

>

>I am still trying to learn assembly language but keep on running into

>problems.

>

>I have been trying to have the following source code assembled:

>

>VIDRAM  EQU     $0400     *Start of Video Display location

>V0CLR   EQU     $FFC0        *Clear bit for Sam Chip (Graphics mode)

>V1SET   EQU     $FFC3        *Set V1 bit in Sam Chip (Graphics mode)

>V2SET   EQU     $FFC5        *set V2 bit in Sam Chip (Graphics mode)

>VOFSET  EQU     $FFC6       *Display Offset Binary, This is the CLR Bit

>(Video page offset)

>VDGSET  EQU     $FF22        *PIA1 data port B: VDG Control output

>POLCAT  EQU     $A000        *Color Basic rom poll keyboard routine

>

>         ORG     $21FD

>         LDX     #VIDRAM   *331D: 8E 04 00

>         LDD     $AAAA     *3320: CC AA AA

>Z3323   STD     ,X++      *3323: ED 81

>         CMPX    #$1C00    *3325: 8C 1C 00

>         BCS     Z3323     *3328: 25 F9

>         NOP               *332A: 12

>PMODE4  STA     V0CLR     *2787: B7 FF C0

>         STA     V1SET     *278A: B7 FF C3

>         STA     V2SET     *278D: B7 FF C5

>         LDA     #$F8      *2790: 86 F8

>         STA     VDGSET    *2792: B7 FF 22

>         STA     VOFSET    *2795: B7 FF C6

>         JSR     [POLCAT]  *332E: AD 9F A0 00

>         RTS               *3332:



The source code above is missing two things:
the label of the starting line/address

try:
EXEC   LDX #VIDRAM

and the LOADM/EXEC finalizer is missing
the last line of the source code should be:

    END  EXEC

Now when you LOADM the program from BASIC, all you have to do is type EXEC
No address is needed as in EXEC #####.
If you just used END without an address, you'd have to type EXEC 
$21FD from BASIC to run the program.


-- 
Roger Taylor

http://www.wordofthedayonline.com