[Coco] Hello World part2

[Roger Taylor]

At 08:32 AM 1/21/2004 -0500, you wrote:
>Here is a slightly modified version of Theodore's Hello World program. It 
>is selectable for true lowercase or color mode for text. Unfortunately 
>numbers and punctuation have only one color set.
>
>* SLIGHTLY MODIFIED PROGRAM POSTED BY THEODORE EVANS
>* NEXT LINE SELECTS BLACK LETTERS GREEN BACKGROUND
>* GREEN LETTERS BLACK BACKGROUND OR TRUE LOWERCASE
>* ON GREEN BACKGROUND
>
>LETTER  EQU     -1      0=BLACK ON GREEN, 1=GREEN ON BLACK, -1=TRUE
>
>* NEXT LINE CAN BE CHANGED OR REMOVED
>         ORG     $7000
>* HELLO, WORLD
>* CLEAR SCREEN
>START    LDX #$0400
>         LDA     #$20
>         COND    LETTER.NEQ.0
>         ADDA    #$40
>         ENDC
>CLRLP    STA ,X+
>         CMPX #$0600
>         BLO CLRLP
>         COND    LETTER.EQU.-1
>         LDA     $FF22
>         ORA     #%00010000      ACTIVATE LOWERCASE
>         STA     $FF22
>         ENDC
>* WRITE 'HELLO, WORLD' TO MIDDLE OF SCREEN
>         LDX #$04EA
>         LDY #HELLO
>WRTLP    LDA ,Y+
>         BEQ     QUIT
>         COND    LETTER.EQU.0
>         CMPA    #$20
>         BEQ     NOFLP
>         ENDC
>         CMPA    #'@
>         BLO     FLIP
>         CMPA    #$60
>         BLO     NOFLP
>         ANDA    #$DF
>FLIP    EORA    #$40
>NOFLP   STA ,X+
>         BNE WRTLP
>QUIT    BRA     QUIT
>HELLO   FCC 'Hello, World'
>         FCB 0
>         END START


I wanted to add for those using CCASM/Portal-9 that all of the operations 
that use the syntax such as ".EQU." have been removed and replaced with the 
more common operator characters like "=" in this case.

The reason for this was to allow dot notation structure names/fields, such 
as "color.red", or "student.name", and even something like "logical.or", 
which would translate into the "or" field of the structure called "logical".

There is also an automatic symbol "." that returns the value of the program 
counter even if embedded within a list of constants, or even an instruction 
such as "LDA #." .  This is not the same as the "*" automatic symbol, but 
it's similar.  "." can be used to return the address of an operand or 
subpart of any instruction or list of data.  Anyway, it's very hard to try 
to implement so many different uses for the "." character without one use 
interfering with the others.  The reason for removing the prehistoric 
.OPERATION. syntax was to make way for a much more powerful feature, and 
that is dot-notated records, structures, and unions.

Some minor things in EDTASM source code that you'll have to change for 
compatibility with CCASM are as follows.

.AND.  -- change to -->   &
.OR.  -- change to -->   !   or  |
.EOR.  -- change to -->   ~
.XOR.  -- change to -->   ~
.NOT.  -- change to -->   ^
.EQU.  -- change to -->   =

A simple find and replace will do the trick.  I've converted tons of source 
already and see no problem other than the fact that you can't assemble the 
resulting CCASM source code from EDTASM any longer.  I guess this is one of 
the things that keeps the two from being identical.

An example of something that needs to be changed:

         ldd     #BIT7.OR.BIT0.AND.BIT3
         lda     #.NOT.5

would become:

         ldd     #BIT7!BIT0&BIT3
         lda     #^5



----------
Roger Taylor