fill.asm: word on top right screen not blackened

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fill.asm: word on top right screen not blackened

računalnik
Hi everyone,

The first step I took for the assignment was to store the memory space of the top left word of the screen to a variable. I'll lay it out by the respective comments for each line here:

        // load the start of the screen's memory map in the A-register
        // Set D-Register equal to that address
        // Declare a new memory space (e.g. "top_left") to save that value
        // Set that memory to what is saved in the D-Register

When doing this whole screen but the very first word of it's memory map blacken when pressing a key. Only if the the last instruction from above is

// Set that memory space to what is saved in the D-Register -1

the whole screen blackens.

Just from the information given, can somebody explain to me why that is? If not I am happy to send my code.

Thanks!


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Re: fill.asm: word on top right screen not blackened

cadet1620
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It sounds like you are incrementing top_left in your loop before you are using it to set the Screen memory.

--Mark  
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