help understanding Pong.asm

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help understanding Pong.asm

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I'm trying to get my assembler code to work with Pong.asm.  The problem I'm having is that some of the A-instructions have names for which there is no corresponding label.  Specifically ones that look like: word.digit, for example: @ponggame.0 is present several times in the code, but there is no (ponggame.0).

I work on this rather sporadically, so I suspect I'm just forgetting some aspect of the syntax.  Can someone give me a hint as to how to handle these?
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Re: help understanding Pong.asm

cadet1620
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I'm trying to get my assembler code to work with Pong.asm.  The problem I'm having is that some of the A-instructions have names for which there is no corresponding label.  Specifically ones that look like: word.digit, for example: @ponggame.0 is present several times in the code, but there is no (ponggame.0).

I work on this rather sporadically, so I suspect I'm just forgetting some aspect of the syntax.  Can someone give me a hint as to how to handle these?
The names on A-instructions that don't have corresponding labels are RAM variables.  During pass 2 when you encounter an undefined name you need to assign it the next available RAM address and add it to the symbol table.

See section 6.3.5 for more details.

--Mark
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Re: help understanding Pong.asm

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Ah, ok, thanks.  That makes sense.  

Got it working now!