In SX Microcontrollers, SX/B Compiler and SX-Key Tool, verobel wrote:

Fellow SXers;
 

I have been slowly learning SX assembler and SX/B over the last few weeks, following 2 books by Al Williams and Gunther Daubach.. My goal is to transfer Robot1 and Speedo1 basic stamp programs to SX28. My initial attempts both failed.. although I was able to get Robot1 compiled in SX/B..but didn't know enough to figure out what was wrong.. so I backtracked and started reading the 2 books and many Nuts&Volts articles by Jon Williams. There is alot of ground to cover but fortunately lots of support in text.

 

I got to pg. 75  Unit 5 and have piezo tones coming out using Program5.1 but then got stuck on similar tone gen. program on pg. 75 in SX/B: my File Prog5d2.SXB. Initially it would not compile because I didn't release _PARAM1 has two underscores. I also could not compile because the IDE would not open a file called Prog5.2.SXB.. works ok with Prog5d2.SXB. Now it compiles but doesn't 'play the music' ..so I've been trying to figure out why.. so I debug/step thru that auto generated code.. and see alot of stuff.. like system param setup (30 lines), system initialize (35 lines), and expansion code for for-next loops, lookup, gosub.. which brings me to the questions.. 

 

I have backed up to easier sample program (by parallax) Toggle.SXB example (to keep it simple) ..it does:

  DO
    PAUSE BlinkDelay                            ' delay
    TOGGLE AlarmLed                             ' toggle LED state
  LOOP  

 

which assembles to (only lines of interest shown):

 

  140  0037  0CFA        MOV __PARAM2,#250              ;    PAUSE BlinkDelay                            ' delay
        0038  0029
   141  0039  0C04        MOV __PARAM3,#4               
        003A  002A
   142  003B  0C1C        MOV __PARAM4,#28              
        003C  002B
   143  003D  02EB        DJNZ __PARAM4,@$              
        003E  0010 0A3D
   144  0040  02EA        DJNZ __PARAM3,@$-3            
        0041  0010 0A3D
   145  0043  02E9        DJNZ __PARAM2,@$-10           
        0044  0010 0A39
   146                  
   147  0046  0CFB        MOV FSR,#__TRISB               ;    TOGGLE AlarmLed                             ' toggle LED state
        0047  0024
   148  0048  0420        CLRB IND.1                    
   149  0049  005F        MODE $0F                      
   150  004A  0200        MOV !RB,IND                   
        004B  0006
   151  004C  0018        BANK $00                      
   152  004D  0C02        XOR RB,#%00000010             
        004E  01A6
   153                  
   154  004F  0010        JMP @__DO_1                    ;  LOOP                                        ' loop forever
        0050  0A37
   155  =00000051       __LOOP_1:    

 

 so I was stepping thru and thinking I am calling a PAUSE routine with 1 param: blinkdelay  but the code looks like it is working with 3 params ( line 141-145) and it loops quite a bit in there (needlessly?) ..is this really necessary.. or how does this work?

 

 I can see how the toggle works and the DO LOOP.

 

 Perhaps someone could explain a bit more about what the intialize code does and when and if it can be dropped.. or for that matter, how it could be dropped? Then a similar explanation for subroutine pass code would be nice. This program (above) works.. I'm just trying to understand what is going on.. so when I look back at the bigger program for tone display.. I can sort out subrt, lookup, pause, and toggle code.. in an effort to figure out why it is not working. I have attached a copy of Prog5d2.SXB ..perhaps someone could scan that too, to spot any obvious problems.. I might have done a typo.

 

Thanks all. John

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