Assembler Guru's.

[Peter Fenske]

Hi Ross

Zounds like you are building a bit flag byte from several different
flag bytes.. I think that ram though is used by the HUD and ecu.

Gl:peter





"Ross Myers" <ponty at axis.jeack.com.au> on 07/08/99 03:52:12 AM

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Hi All,

Been flicking through the code of some Holden stuff lately, and came across
the following, can any of you figure what this maybe used for, This code
structure continues for a fair while and occasionally jumps to some other
running code at $5xxx. An example -

180A CLRA
180B BRCLR $57,$40,$02    (1811 
)
180F ORAA  #$80
1811 TST   $02C9
1814 BEQ   $02            (1818 
)
1816 ORAA  #$40
1818 BRCLR $50,$02,$02    (181E 
)
181C ORAA  #$20
181E BRCLR $8E,$01,$02    (1824 
)
1822 ORAA  #$10
1824 BRCLR $62,$04,$02    (182A 
)
1828 ORAA  #$08
182A BRCLR $61,$01,$02    (1830 
)
182E ORAA  #$04
1830 BRSET $57,$01,$02    (1836 
)
1834 ORAA  #$02
1836 BRCLR $62,$01,$02    (183C 
)
183A ORAA  #$01
183C STAA  $0488
183F CLRA

Any help appreciated as always.

Ross Myers