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RAM/Variables

While finding routines, we can also start naming addresses to RAM/variables. Let's look at an example from earlier when we were Mapping code vs. data areas. We came across and defined a data region t_snsrChkBit

...
E0CD 7E E5 F2    L4345               jmp     $e5f2
E0D0 86 86                           ldaa    #$86
E0D2 C6 8A                           ldab    #$8a
E0D4 97 ED                           staa    $ed
E0D6 97 EF                           staa    $ef
E0D8 D7 EE                           stab    $ee
E0DA 39                              rts     
E0DB 02 00 40 00 t_snsrChkBit        .byte   $02, $00, $40, $00
E0DF 80 00 00 01                     .byte   $80, $00, $00, $01
...

In the E391 listing, above the t_snsrChkBit table

standard_E931.lst
...
E518 86 86                   ldaa    #$86                                               
E51A C6 8A                   ldab    #$8a                                               
...       
6477   E51C 97 ED       L1448       staa    iscY0                                                 
6478   E51E 97 EF                   staa    iscY2                                                 
6479   E520 D7 EE                   stab    iscY1                                                 
6480   E522 39                      rts                        
...

So now we know, EDh = iscY0, EFh = iscY2, and EEh = iscY1

Here is a list of the RAM/Variables from the E931 symbol file. Use the names as a starting point for finding the right addresses

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