[Coco] Direct page register question
zippster278 at gmail.com
Tue Oct 30 16:25:57 EDT 2018
I prefer to just use the ‘<‘. It doesn’t hurt to be explicit after all here.
Also if you’re using a label, it makes it more obvious (to me at least)
that direct addressing is being used.
But whatever the programmer is more comfortable with of course.
> On Oct 30, 2018, at 3:10 PM, Ciaran Anscomb <cocomalt at 6809.org.uk> wrote:
> William Astle wrote:
>> LDA SYMBOL
>> SYMBOL EQU $85
>> This will probably use extended addressing because during pass one, the
>> assembler hasn't seen the definition of SYMBOL yet when it gets to the
>> LDA instruction so it has to assume full 16 bit addressing.
>> This is actually one of the reasons you should define your variables at
>> the start of the program, especially if the direct page is going to be
> Or use an n-pass assembler which generates another pass if addressing
> isn't stable! Native assemblers likely going to be limited, but a
> cross-assembler might do it. e.g., asm6809 output:
> 4000 org $4000
> 4000 setdp $00
> 4000 9685 lda symbol
> 0085 symbol equ $85
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