Code: Learning Disassembly Assembly

[EagleMark]

From 1project2many:

EagleMark's post below made me realize it would be a good idea to have a place for code questions. Anything goes, so to speak, as long as it's code related. Assembly, Modula, C++, Motorola, Intel, Whatever.

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$4F XDF Fuel VE table goes to 5200 RPM, but the assembly only goes to 4800? Somone started at 400 RPM instead of 0 RPM.

Odd? Have you ever seen how much Air managmant code is in a $6E assembly? And I can't find a way to turn it off? In $42 it's just a temp on and timer...

Since I'm stating to understand looups and sub routines how about a lesson on the commands? I just grabbed this piece and BOLD, Italic and UNDERLINED some examples.

                 ;--------------------
                ; LK UP  ACCEL ENRICH 
                ; vs Diff TPS 
                ; ** PUMP SHOT **
                ;--------------------
D775:            LDAA    #255
D777:  LD777     LDX     #$D312         ; ACCEL ENRICH vs Diff TPS TBL
                                        ; Contrib vs Diff TPS TBL
D77A:            JSR     LFAD7          ; 2D LK UP 
 ;                                                            
D77D:            LDAB    L00DF
D77F:            ORAB    #$10           ; BIT 4
D781:            BRA     LD786
 ;                                                            
D783:  LD783     CLRA    
D784:            ANDB    #$EF       ; 0111 1111
D786:  LD786     STAB    L00DF
D788:            STAA    L0058      ; BPW, MSB
D78A:            STAA    L009A
D78C:            CLRA    
D78D:            LDAB    L00DF
D78F:            BITB    #4         ; BIT 2
D791:            BEQ     LD796
 ;                                                            
D793:            LDAA    LD28F      ; 183 Usec, BPW ADDER TO BPW WHILE 
                                    ; IAC IS OPENING
                                    ; VAL MSEC = 16.384 
                                    
D796:  LD796     ADDA    L0058      ; BPW, MSB
D798:            BCS     LD79E
                                    ; ... else                               
D79A:            ADDA    L0059      ; BPW, LSB
D79C:            BCC     LD7A0
                                    ; ... else    
D79E:  LD79E     LDAA    #255       ; MAX LMT
D7A0:  LD7A0     BEQ     LD7BE
 ;                                                            
D7A2:            LDAB    L0098
D7A4:            MUL     
D7A5:            LSRD               ; DIV BY 8
D7A6:            LSRD    
D7A7:            LSRD    
D7A8:            ADDD    L0096
D7AA:            STD     L0096
D7AC:            LDAB    L0006
D7AE:            LDAA    L000D
D7B0:            BITA    #$40       ; BIT 6
D7B2:            BNE     LD7B6
                                    ; ...... else                         
D7B4:            ORAB    #8
D7B6:  LD7B6     ORAA    #$C0       ; 1100 0000
D7B8:            ORAB    #1         ; BIT 0
D7BA:            STAB    L0006
D7BC:            BRA     LD7C2
                                                            
D7BE:  LD7BE     LDAA    L000D
D7C0:            ANDA    #$BF       ; 1011 1111
D7C2:  LD7C2     STAA    L000D
D7C4:            LDAB    L0072
D7C6:            BITB    #2         ; BIT 1
D7C8:            BEQ     LD7DD

Code: Learning Disassembly Assembly