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System Specification for C65Fred BowenMarch 1, 1991

Number of cycles per line

In "slow" CPU mode...

    Total cycles no video                     65
    40 column SCM, MCM, ECM, BMM,
    320 pixel BPM, BPO-BP3 only, or
    640 pixel BPM, BPO-BP1 only     no cost    0
    80 column SCM, MCM, ECM, BMM,
    320 pixel BPM, BPO-BP7, or
    640 pixel BPM, BPO-BP3          substarct 40
    Sprites                         substract  2 per active sprite

Examples...

    
 No video on line                             65
 40 column text or equiv. BPS (no sprites)    65
 80 column text or equiv. BPS (no sprites)    25
 80 column text or equiv. BPS, all sprites     9 -- worst case
    
        227 memory cycles/line
        6 refresh
        0-32 sprite
        0,40,80,120,160 video
    
        fast    slow
        ----    ----
        277     138     total cycles/line
        -6      -3      refresh
        -32     -16     sprites
        ---     ----
        239     119     avail CPU cycles/line (no video)
    
    
        no        1       2       3       4
        video   fetch   fetch   fetch   fetch
        ------  ------  ------  ------  -------
 cpucyc 239     199     159     119     79      all sprites (fast)
 cpucyc 271     231     191     151     111     no sprites (fast)
 cpucyc 119     79      79      39      39      all sprites (slow)
 cpucyc 135     95      95      55      55      nosprites (slow)



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