Improvements

The assembler seems to have some interesting/useful features.

        DC.B     R2 | G1              
        DC.B     R2 | G1              
        DC.B     R2 | G1

could simply be replaced with

        DC.B [3] R2 | G1

It's also possible to pass parameters into macros.

SEQ9    MACRO   red,redyellow
        DC.B    [red      ] R2
        DC.B    [redyellow] R2 | Y2
        ENDM

        SEQ9 4,2

would do the same as four lines of "DC.B R2",
followed by two lines of "DC.B R2 | Y2".

We could as well pass the constants for the colour through:

SEQ8    MACRO   col1,num1,col2,num2
        DC.B    [num1] col1
        DC.B    [num2] col2
        ENDM

        SEQ8    R2, 4, R2|Y2, 2

Now for something peculiar/weird:

SEQ7    MACRO   col1,col2,total,num2percent
        DC.B    [100-(total/100)*num2percent] col1
        DC.B    [    (total/100)*num2percent] col2
        ENDM

        SEQ7    R2, R2|Y2, 200, 5

What gives us 200 Bytes:
First 190 Bytes (95 percent) are set to $08 (190 times "DC.B R2"),
followed by 10 Bytes (5 percent) that are set to $18 ("DC.B R2 | Y2").
Keep in mind, that there seems to be a size limit.

Only one output Bit left.
What, if we need another traffic light ?

DC.W defines a 16 Bit constant (Word),
DC.L defines a 32 Bit constant (Long).

But when using them, we have to be aware,
what end of the egg the assembler opens for breakfast... just kidding.

"Little endian format" means, the little end of a value in memory
is at the lowest memory address (as known from 80x86).
A 32 Bit constant like $12345678 would end up as $78 $56 $34 $12 in memory.

"Big endian format" means, that the big end of a value in memory
is at the lowest memory address (as known from 68000).
$12345678 would give $12 $34 $56 $78 in memory.

At the moment, we are using big endian.
Some EPROM programming tools support Byte splitting, some don't.
In that case, we have to write our own tool to split 32 Bit values into 4 Bytes.
A little C program that uses fgetc() and fputc() should do it.
Just be aware of the Byte_order/endianess.

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